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| author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-18 02:49:50 +0000 |
|---|---|---|
| committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-18 02:49:50 +0000 |
| commit | 9835e2ae736235810b4ea1c162ca5e65c547e770 (patch) | |
| tree | 3fcebf40ed70e581d776a8a4c65923e8ec20e026 /library/core | |
| parent | Releasing progress-linux version 1.70.0+dfsg2-1~progress7.99u1. (diff) | |
| download | rustc-9835e2ae736235810b4ea1c162ca5e65c547e770.tar.xz rustc-9835e2ae736235810b4ea1c162ca5e65c547e770.zip | |
Merging upstream version 1.71.1+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'library/core')
133 files changed, 4317 insertions, 2675 deletions
diff --git a/library/core/benches/fmt.rs b/library/core/benches/fmt.rs index ff726ff75..d1cdb12e5 100644 --- a/library/core/benches/fmt.rs +++ b/library/core/benches/fmt.rs @@ -1,13 +1,13 @@ use std::fmt::{self, Write as FmtWrite}; use std::io::{self, Write as IoWrite}; -use test::Bencher; +use test::{black_box, Bencher}; #[bench] fn write_vec_value(bh: &mut Bencher) { bh.iter(|| { let mut mem = Vec::new(); for _ in 0..1000 { - mem.write_all("abc".as_bytes()).unwrap(); + mem.write_all(black_box("abc").as_bytes()).unwrap(); } }); } @@ -18,7 +18,7 @@ fn write_vec_ref(bh: &mut Bencher) { let mut mem = Vec::new(); let wr = &mut mem as &mut dyn io::Write; for _ in 0..1000 { - wr.write_all("abc".as_bytes()).unwrap(); + wr.write_all(black_box("abc").as_bytes()).unwrap(); } }); } @@ -29,7 +29,7 @@ fn write_vec_macro1(bh: &mut Bencher) { let mut mem = Vec::new(); let wr = &mut mem as &mut dyn io::Write; for _ in 0..1000 { - write!(wr, "abc").unwrap(); + write!(wr, "{}", black_box("abc")).unwrap(); } }); } @@ -40,7 +40,7 @@ fn write_vec_macro2(bh: &mut Bencher) { let mut mem = Vec::new(); let wr = &mut mem as &mut dyn io::Write; for _ in 0..1000 { - write!(wr, "{}", "abc").unwrap(); + write!(wr, "{}", black_box("abc")).unwrap(); } }); } @@ -51,7 +51,7 @@ fn write_vec_macro_debug(bh: &mut Bencher) { let mut mem = Vec::new(); let wr = &mut mem as &mut dyn io::Write; for _ in 0..1000 { - write!(wr, "{:?}", "☃").unwrap(); + write!(wr, "{:?}", black_box("☃")).unwrap(); } }); } @@ -61,7 +61,7 @@ fn write_str_value(bh: &mut Bencher) { bh.iter(|| { let mut mem = String::new(); for _ in 0..1000 { - mem.write_str("abc").unwrap(); + mem.write_str(black_box("abc")).unwrap(); } }); } @@ -72,7 +72,7 @@ fn write_str_ref(bh: &mut Bencher) { let mut mem = String::new(); let wr = &mut mem as &mut dyn fmt::Write; for _ in 0..1000 { - wr.write_str("abc").unwrap(); + wr.write_str(black_box("abc")).unwrap(); } }); } @@ -82,7 +82,7 @@ fn write_str_macro1(bh: &mut Bencher) { bh.iter(|| { let mut mem = String::new(); for _ in 0..1000 { - write!(mem, "abc").unwrap(); + write!(mem, "{}", black_box("abc")).unwrap(); } }); } @@ -93,7 +93,7 @@ fn write_str_macro2(bh: &mut Bencher) { let mut mem = String::new(); let wr = &mut mem as &mut dyn fmt::Write; for _ in 0..1000 { - write!(wr, "{}", "abc").unwrap(); + write!(wr, "{}", black_box("abc")).unwrap(); } }); } @@ -104,7 +104,7 @@ fn write_str_macro_debug(bh: &mut Bencher) { let mut mem = String::new(); let wr = &mut mem as &mut dyn fmt::Write; for _ in 0..1000 { - write!(wr, "{:?}", "☃").unwrap(); + write!(wr, "{:?}", black_box("☃")).unwrap(); } }); } @@ -115,7 +115,7 @@ fn write_str_macro_debug_ascii(bh: &mut Bencher) { let mut mem = String::new(); let wr = &mut mem as &mut dyn fmt::Write; for _ in 0..1000 { - write!(wr, "{:?}", "Hello, World!").unwrap(); + write!(wr, "{:?}", black_box("Hello, World!")).unwrap(); } }); } diff --git a/library/core/benches/iter.rs b/library/core/benches/iter.rs index 9193c79be..60ef83223 100644 --- a/library/core/benches/iter.rs +++ b/library/core/benches/iter.rs @@ -404,7 +404,7 @@ fn bench_trusted_random_access_adapters(b: &mut Bencher) { /// Exercises the iter::Copied specialization for slice::Iter #[bench] -fn bench_copied_chunks(b: &mut Bencher) { +fn bench_next_chunk_copied(b: &mut Bencher) { let v = vec![1u8; 1024]; b.iter(|| { @@ -421,7 +421,7 @@ fn bench_copied_chunks(b: &mut Bencher) { /// Exercises the TrustedRandomAccess specialization in ArrayChunks #[bench] -fn bench_trusted_random_access_chunks(b: &mut Bencher) { +fn bench_next_chunk_trusted_random_access(b: &mut Bencher) { let v = vec![1u8; 1024]; b.iter(|| { @@ -437,3 +437,45 @@ fn bench_trusted_random_access_chunks(b: &mut Bencher) { .sum::<Wrapping<u64>>() }) } + +#[bench] +fn bench_next_chunk_filter_even(b: &mut Bencher) { + let a = (0..1024).next_chunk::<1024>().unwrap(); + + b.iter(|| black_box(&a).iter().filter(|&&i| i % 2 == 0).next_chunk::<32>()) +} + +#[bench] +fn bench_next_chunk_filter_predictably_true(b: &mut Bencher) { + let a = (0..1024).next_chunk::<1024>().unwrap(); + + b.iter(|| black_box(&a).iter().filter(|&&i| i < 100).next_chunk::<32>()) +} + +#[bench] +fn bench_next_chunk_filter_mostly_false(b: &mut Bencher) { + let a = (0..1024).next_chunk::<1024>().unwrap(); + + b.iter(|| black_box(&a).iter().filter(|&&i| i > 900).next_chunk::<32>()) +} + +#[bench] +fn bench_next_chunk_filter_map_even(b: &mut Bencher) { + let a = (0..1024).next_chunk::<1024>().unwrap(); + + b.iter(|| black_box(&a).iter().filter_map(|&i| (i % 2 == 0).then(|| i)).next_chunk::<32>()) +} + +#[bench] +fn bench_next_chunk_filter_map_predictably_true(b: &mut Bencher) { + let a = (0..1024).next_chunk::<1024>().unwrap(); + + b.iter(|| black_box(&a).iter().filter_map(|&i| (i < 100).then(|| i)).next_chunk::<32>()) +} + +#[bench] +fn bench_next_chunk_filter_map_mostly_false(b: &mut Bencher) { + let a = (0..1024).next_chunk::<1024>().unwrap(); + + b.iter(|| black_box(&a).iter().filter_map(|&i| (i > 900).then(|| i)).next_chunk::<32>()) +} diff --git a/library/core/benches/num/dec2flt/mod.rs b/library/core/benches/num/dec2flt/mod.rs index 305baa687..fb4a786b2 100644 --- a/library/core/benches/num/dec2flt/mod.rs +++ b/library/core/benches/num/dec2flt/mod.rs @@ -1,57 +1,57 @@ -use test::Bencher; +use test::{black_box, Bencher}; #[bench] fn bench_0(b: &mut Bencher) { - b.iter(|| "0.0".parse::<f64>()); + b.iter(|| black_box("0.0").parse::<f64>()); } #[bench] fn bench_42(b: &mut Bencher) { - b.iter(|| "42".parse::<f64>()); + b.iter(|| black_box("42").parse::<f64>()); } #[bench] fn bench_huge_int(b: &mut Bencher) { // 2^128 - 1 - b.iter(|| "170141183460469231731687303715884105727".parse::<f64>()); + b.iter(|| black_box("170141183460469231731687303715884105727").parse::<f64>()); } #[bench] fn bench_short_decimal(b: &mut Bencher) { - b.iter(|| "1234.5678".parse::<f64>()); + b.iter(|| black_box("1234.5678").parse::<f64>()); } #[bench] fn bench_pi_long(b: &mut Bencher) { - b.iter(|| "3.14159265358979323846264338327950288".parse::<f64>()); + b.iter(|| black_box("3.14159265358979323846264338327950288").parse::<f64>()); } #[bench] fn bench_pi_short(b: &mut Bencher) { - b.iter(|| "3.141592653589793".parse::<f64>()) + b.iter(|| black_box("3.141592653589793").parse::<f64>()) } #[bench] fn bench_1e150(b: &mut Bencher) { - b.iter(|| "1e150".parse::<f64>()); + b.iter(|| black_box("1e150").parse::<f64>()); } #[bench] fn bench_long_decimal_and_exp(b: &mut Bencher) { - b.iter(|| "727501488517303786137132964064381141071e-123".parse::<f64>()); + b.iter(|| black_box("727501488517303786137132964064381141071e-123").parse::<f64>()); } #[bench] fn bench_min_subnormal(b: &mut Bencher) { - b.iter(|| "5e-324".parse::<f64>()); + b.iter(|| black_box("5e-324").parse::<f64>()); } #[bench] fn bench_min_normal(b: &mut Bencher) { - b.iter(|| "2.2250738585072014e-308".parse::<f64>()); + b.iter(|| black_box("2.2250738585072014e-308").parse::<f64>()); } #[bench] fn bench_max(b: &mut Bencher) { - b.iter(|| "1.7976931348623157e308".parse::<f64>()); + b.iter(|| black_box("1.7976931348623157e308").parse::<f64>()); } diff --git a/library/core/benches/num/flt2dec/mod.rs b/library/core/benches/num/flt2dec/mod.rs index 32fd5e626..1a330ef5f 100644 --- a/library/core/benches/num/flt2dec/mod.rs +++ b/library/core/benches/num/flt2dec/mod.rs @@ -7,7 +7,7 @@ use core::num::flt2dec::MAX_SIG_DIGITS; use core::num::flt2dec::{decode, DecodableFloat, Decoded, FullDecoded}; use std::io::Write; use std::vec::Vec; -use test::Bencher; +use test::{black_box, Bencher}; pub fn decode_finite<T: DecodableFloat>(v: T) -> Decoded { match decode(v).1 { @@ -22,7 +22,7 @@ fn bench_small_shortest(b: &mut Bencher) { b.iter(|| { buf.clear(); - write!(&mut buf, "{}", 3.1415926f64).unwrap() + write!(black_box(&mut buf), "{}", black_box(3.1415926f64)).unwrap() }); } @@ -32,6 +32,6 @@ fn bench_big_shortest(b: &mut Bencher) { b.iter(|| { buf.clear(); - write!(&mut buf, "{}", f64::MAX).unwrap() + write!(black_box(&mut buf), "{}", black_box(f64::MAX)).unwrap() }); } diff --git a/library/core/benches/num/flt2dec/strategy/grisu.rs b/library/core/benches/num/flt2dec/strategy/grisu.rs index 6bea5e55d..17d6b474a 100644 --- a/library/core/benches/num/flt2dec/strategy/grisu.rs +++ b/library/core/benches/num/flt2dec/strategy/grisu.rs @@ -81,3 +81,30 @@ fn bench_big_exact_inf(b: &mut Bencher) { format_exact(black_box(&decoded), &mut buf, i16::MIN); }); } + +#[bench] +fn bench_one_exact_inf(b: &mut Bencher) { + let decoded = decode_finite(1.0); + let mut buf = [MaybeUninit::new(0); 1024]; + b.iter(|| { + format_exact(black_box(&decoded), &mut buf, i16::MIN); + }); +} + +#[bench] +fn bench_trailing_zero_exact_inf(b: &mut Bencher) { + let decoded = decode_finite(250.000000000000000000000000); + let mut buf = [MaybeUninit::new(0); 1024]; + b.iter(|| { + format_exact(black_box(&decoded), &mut buf, i16::MIN); + }); +} + +#[bench] +fn bench_halfway_point_exact_inf(b: &mut Bencher) { + let decoded = decode_finite(1.00000000000000011102230246251565404236316680908203125); + let mut buf = [MaybeUninit::new(0); 1024]; + b.iter(|| { + format_exact(black_box(&decoded), &mut buf, i16::MIN); + }); +} diff --git a/library/core/benches/num/mod.rs b/library/core/benches/num/mod.rs index 2f9cad272..b97014d9b 100644 --- a/library/core/benches/num/mod.rs +++ b/library/core/benches/num/mod.rs @@ -3,7 +3,7 @@ mod flt2dec; mod int_log; use std::str::FromStr; -use test::Bencher; +use test::{black_box, Bencher}; const ASCII_NUMBERS: [&str; 19] = [ "0", @@ -36,7 +36,7 @@ macro_rules! from_str_bench { .iter() .cycle() .take(5_000) - .filter_map(|s| <$t>::from_str(s).ok()) + .filter_map(|s| <$t>::from_str(black_box(s)).ok()) .max() }) } @@ -52,7 +52,7 @@ macro_rules! from_str_radix_bench { .iter() .cycle() .take(5_000) - .filter_map(|s| <$t>::from_str_radix(s, $radix).ok()) + .filter_map(|s| <$t>::from_str_radix(black_box(s), $radix).ok()) .max() }) } diff --git a/library/core/src/alloc/global.rs b/library/core/src/alloc/global.rs index 18da70451..c58211170 100644 --- a/library/core/src/alloc/global.rs +++ b/library/core/src/alloc/global.rs @@ -235,7 +235,8 @@ pub unsafe trait GlobalAlloc { /// * `new_size` must be greater than zero. /// /// * `new_size`, when rounded up to the nearest multiple of `layout.align()`, - /// must not overflow (i.e., the rounded value must be less than `usize::MAX`). + /// must not overflow isize (i.e., the rounded value must be less than or + /// equal to `isize::MAX`). /// /// (Extension subtraits might provide more specific bounds on /// behavior, e.g., guarantee a sentinel address or a null pointer diff --git a/library/core/src/alloc/layout.rs b/library/core/src/alloc/layout.rs index ac3d84718..597303037 100644 --- a/library/core/src/alloc/layout.rs +++ b/library/core/src/alloc/layout.rs @@ -231,9 +231,8 @@ impl Layout { /// Returns an error if the combination of `self.size()` and the given /// `align` violates the conditions listed in [`Layout::from_size_align`]. #[stable(feature = "alloc_layout_manipulation", since = "1.44.0")] - #[rustc_const_unstable(feature = "const_alloc_layout", issue = "67521")] #[inline] - pub const fn align_to(&self, align: usize) -> Result<Self, LayoutError> { + pub fn align_to(&self, align: usize) -> Result<Self, LayoutError> { Layout::from_size_align(self.size(), cmp::max(self.align(), align)) } @@ -315,9 +314,8 @@ impl Layout { /// /// On arithmetic overflow, returns `LayoutError`. #[unstable(feature = "alloc_layout_extra", issue = "55724")] - #[rustc_const_unstable(feature = "const_alloc_layout", issue = "67521")] #[inline] - pub const fn repeat(&self, n: usize) -> Result<(Self, usize), LayoutError> { + pub fn repeat(&self, n: usize) -> Result<(Self, usize), LayoutError> { // This cannot overflow. Quoting from the invariant of Layout: // > `size`, when rounded up to the nearest multiple of `align`, // > must not overflow isize (i.e., the rounded value must be @@ -376,9 +374,8 @@ impl Layout { /// # assert_eq!(repr_c(&[u64, u32, u16, u32]), Ok((s, vec![0, 8, 12, 16]))); /// ``` #[stable(feature = "alloc_layout_manipulation", since = "1.44.0")] - #[rustc_const_unstable(feature = "const_alloc_layout", issue = "67521")] #[inline] - pub const fn extend(&self, next: Self) -> Result<(Self, usize), LayoutError> { + pub fn extend(&self, next: Self) -> Result<(Self, usize), LayoutError> { let new_align = cmp::max(self.align, next.align); let pad = self.padding_needed_for(next.align()); @@ -403,9 +400,8 @@ impl Layout { /// /// On arithmetic overflow, returns `LayoutError`. #[unstable(feature = "alloc_layout_extra", issue = "55724")] - #[rustc_const_unstable(feature = "const_alloc_layout", issue = "67521")] #[inline] - pub const fn repeat_packed(&self, n: usize) -> Result<Self, LayoutError> { + pub fn repeat_packed(&self, n: usize) -> Result<Self, LayoutError> { let size = self.size().checked_mul(n).ok_or(LayoutError)?; // The safe constructor is called here to enforce the isize size limit. Layout::from_size_alignment(size, self.align) @@ -418,9 +414,8 @@ impl Layout { /// /// On arithmetic overflow, returns `LayoutError`. #[unstable(feature = "alloc_layout_extra", issue = "55724")] - #[rustc_const_unstable(feature = "const_alloc_layout", issue = "67521")] #[inline] - pub const fn extend_packed(&self, next: Self) -> Result<Self, LayoutError> { + pub fn extend_packed(&self, next: Self) -> Result<Self, LayoutError> { let new_size = self.size().checked_add(next.size()).ok_or(LayoutError)?; // The safe constructor is called here to enforce the isize size limit. Layout::from_size_alignment(new_size, self.align) diff --git a/library/core/src/alloc/mod.rs b/library/core/src/alloc/mod.rs index ff390322d..d6ae2b821 100644 --- a/library/core/src/alloc/mod.rs +++ b/library/core/src/alloc/mod.rs @@ -105,7 +105,6 @@ impl fmt::Display for AllocError { /// /// [*currently allocated*]: #currently-allocated-memory #[unstable(feature = "allocator_api", issue = "32838")] -#[const_trait] pub unsafe trait Allocator { /// Attempts to allocate a block of memory. /// diff --git a/library/core/src/any.rs b/library/core/src/any.rs index c27646b8f..7969f4055 100644 --- a/library/core/src/any.rs +++ b/library/core/src/any.rs @@ -662,13 +662,20 @@ impl dyn Any + Send + Sync { /// While `TypeId` implements `Hash`, `PartialOrd`, and `Ord`, it is worth /// noting that the hashes and ordering will vary between Rust releases. Beware /// of relying on them inside of your code! -#[derive(Clone, Copy, Debug, Hash, Eq)] -#[derive_const(PartialEq, PartialOrd, Ord)] +#[derive(Clone, Copy, Debug, Hash, Eq, PartialOrd, Ord)] #[stable(feature = "rust1", since = "1.0.0")] pub struct TypeId { t: u64, } +#[stable(feature = "rust1", since = "1.0.0")] +impl PartialEq for TypeId { + #[inline] + fn eq(&self, other: &Self) -> bool { + self.t == other.t + } +} + impl TypeId { /// Returns the `TypeId` of the type this generic function has been /// instantiated with. @@ -867,7 +874,7 @@ where /// /// A data provider provides values by calling this type's provide methods. #[unstable(feature = "provide_any", issue = "96024")] -#[repr(transparent)] +#[cfg_attr(not(doc), repr(transparent))] // work around https://github.com/rust-lang/rust/issues/90435 pub struct Demand<'a>(dyn Erased<'a> + 'a); impl<'a> Demand<'a> { diff --git a/library/core/src/array/ascii.rs b/library/core/src/array/ascii.rs new file mode 100644 index 000000000..3fea9a440 --- /dev/null +++ b/library/core/src/array/ascii.rs @@ -0,0 +1,47 @@ +use crate::ascii; + +#[cfg(not(test))] +impl<const N: usize> [u8; N] { + /// Converts this array of bytes into a array of ASCII characters, + /// or returns `None` if any of the characters is non-ASCII. + /// + /// # Examples + /// + /// ``` + /// #![feature(ascii_char)] + /// #![feature(const_option)] + /// + /// const HEX_DIGITS: [std::ascii::Char; 16] = + /// *b"0123456789abcdef".as_ascii().unwrap(); + /// + /// assert_eq!(HEX_DIGITS[1].as_str(), "1"); + /// assert_eq!(HEX_DIGITS[10].as_str(), "a"); + /// ``` + #[unstable(feature = "ascii_char", issue = "110998")] + #[must_use] + #[inline] + pub const fn as_ascii(&self) -> Option<&[ascii::Char; N]> { + if self.is_ascii() { + // SAFETY: Just checked that it's ASCII + Some(unsafe { self.as_ascii_unchecked() }) + } else { + None + } + } + + /// Converts this array of bytes into a array of ASCII characters, + /// without checking whether they're valid. + /// + /// # Safety + /// + /// Every byte in the array must be in `0..=127`, or else this is UB. + #[unstable(feature = "ascii_char", issue = "110998")] + #[must_use] + #[inline] + pub const unsafe fn as_ascii_unchecked(&self) -> &[ascii::Char; N] { + let byte_ptr: *const [u8; N] = self; + let ascii_ptr = byte_ptr as *const [ascii::Char; N]; + // SAFETY: The caller promised all the bytes are ASCII + unsafe { &*ascii_ptr } + } +} diff --git a/library/core/src/array/iter.rs b/library/core/src/array/iter.rs index 73e2c2cfb..587877dff 100644 --- a/library/core/src/array/iter.rs +++ b/library/core/src/array/iter.rs @@ -3,8 +3,9 @@ use crate::num::NonZeroUsize; use crate::{ fmt, + intrinsics::transmute_unchecked, iter::{self, ExactSizeIterator, FusedIterator, TrustedLen}, - mem::{self, MaybeUninit}, + mem::MaybeUninit, ops::{IndexRange, Range}, ptr, }; @@ -63,18 +64,11 @@ impl<T, const N: usize> IntoIterator for [T; N] { // an array of `T`. // // With that, this initialization satisfies the invariants. - - // FIXME(LukasKalbertodt): actually use `mem::transmute` here, once it - // works with const generics: - // `mem::transmute::<[T; N], [MaybeUninit<T>; N]>(array)` // - // Until then, we can use `mem::transmute_copy` to create a bitwise copy - // as a different type, then forget `array` so that it is not dropped. - unsafe { - let iter = IntoIter { data: mem::transmute_copy(&self), alive: IndexRange::zero_to(N) }; - mem::forget(self); - iter - } + // FIXME: If normal `transmute` ever gets smart enough to allow this + // directly, use it instead of `transmute_unchecked`. + let data: [MaybeUninit<T>; N] = unsafe { transmute_unchecked(self) }; + IntoIter { data, alive: IndexRange::zero_to(N) } } } diff --git a/library/core/src/array/mod.rs b/library/core/src/array/mod.rs index 1643842d6..fec92320a 100644 --- a/library/core/src/array/mod.rs +++ b/library/core/src/array/mod.rs @@ -17,6 +17,7 @@ use crate::ops::{ }; use crate::slice::{Iter, IterMut}; +mod ascii; mod drain; mod equality; mod iter; @@ -148,8 +149,7 @@ impl Error for TryFromSliceError { } #[stable(feature = "try_from_slice_error", since = "1.36.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl const From<Infallible> for TryFromSliceError { +impl From<Infallible> for TryFromSliceError { fn from(x: Infallible) -> TryFromSliceError { match x {} } @@ -172,16 +172,14 @@ impl<T, const N: usize> AsMut<[T]> for [T; N] { } #[stable(feature = "array_borrow", since = "1.4.0")] -#[rustc_const_unstable(feature = "const_borrow", issue = "91522")] -impl<T, const N: usize> const Borrow<[T]> for [T; N] { +impl<T, const N: usize> Borrow<[T]> for [T; N] { fn borrow(&self) -> &[T] { self } } #[stable(feature = "array_borrow", since = "1.4.0")] -#[rustc_const_unstable(feature = "const_borrow", issue = "91522")] -impl<T, const N: usize> const BorrowMut<[T]> for [T; N] { +impl<T, const N: usize> BorrowMut<[T]> for [T; N] { fn borrow_mut(&mut self) -> &mut [T] { self } @@ -206,6 +204,7 @@ where { type Error = TryFromSliceError; + #[inline] fn try_from(slice: &[T]) -> Result<[T; N], TryFromSliceError> { <&Self>::try_from(slice).map(|r| *r) } @@ -230,6 +229,7 @@ where { type Error = TryFromSliceError; + #[inline] fn try_from(slice: &mut [T]) -> Result<[T; N], TryFromSliceError> { <Self>::try_from(&*slice) } @@ -251,7 +251,8 @@ where impl<'a, T, const N: usize> TryFrom<&'a [T]> for &'a [T; N] { type Error = TryFromSliceError; - fn try_from(slice: &[T]) -> Result<&[T; N], TryFromSliceError> { + #[inline] + fn try_from(slice: &'a [T]) -> Result<&'a [T; N], TryFromSliceError> { if slice.len() == N { let ptr = slice.as_ptr() as *const [T; N]; // SAFETY: ok because we just checked that the length fits @@ -278,7 +279,8 @@ impl<'a, T, const N: usize> TryFrom<&'a [T]> for &'a [T; N] { impl<'a, T, const N: usize> TryFrom<&'a mut [T]> for &'a mut [T; N] { type Error = TryFromSliceError; - fn try_from(slice: &mut [T]) -> Result<&mut [T; N], TryFromSliceError> { + #[inline] + fn try_from(slice: &'a mut [T]) -> Result<&'a mut [T; N], TryFromSliceError> { if slice.len() == N { let ptr = slice.as_mut_ptr() as *mut [T; N]; // SAFETY: ok because we just checked that the length fits @@ -293,7 +295,6 @@ impl<'a, T, const N: usize> TryFrom<&'a mut [T]> for &'a mut [T; N] { /// as required by the `Borrow` implementation. /// /// ``` -/// #![feature(build_hasher_simple_hash_one)] /// use std::hash::BuildHasher; /// /// let b = std::collections::hash_map::RandomState::new(); @@ -336,10 +337,9 @@ impl<'a, T, const N: usize> IntoIterator for &'a mut [T; N] { } #[stable(feature = "index_trait_on_arrays", since = "1.50.0")] -#[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -impl<T, I, const N: usize> const Index<I> for [T; N] +impl<T, I, const N: usize> Index<I> for [T; N] where - [T]: ~const Index<I>, + [T]: Index<I>, { type Output = <[T] as Index<I>>::Output; @@ -350,10 +350,9 @@ where } #[stable(feature = "index_trait_on_arrays", since = "1.50.0")] -#[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -impl<T, I, const N: usize> const IndexMut<I> for [T; N] +impl<T, I, const N: usize> IndexMut<I> for [T; N] where - [T]: ~const IndexMut<I>, + [T]: IndexMut<I>, { #[inline] fn index_mut(&mut self, index: I) -> &mut Self::Output { @@ -435,8 +434,7 @@ impl<T: Copy> SpecArrayClone for T { macro_rules! array_impl_default { {$n:expr, $t:ident $($ts:ident)*} => { #[stable(since = "1.4.0", feature = "array_default")] - #[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] - impl<T> const Default for [T; $n] where T: ~const Default { + impl<T> Default for [T; $n] where T: Default { fn default() -> [T; $n] { [$t::default(), $($ts::default()),*] } @@ -445,8 +443,7 @@ macro_rules! array_impl_default { }; {$n:expr,} => { #[stable(since = "1.4.0", feature = "array_default")] - #[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] - impl<T> const Default for [T; $n] { + impl<T> Default for [T; $n] { fn default() -> [T; $n] { [] } } }; diff --git a/library/core/src/ascii.rs b/library/core/src/ascii.rs index 8a4cb78cc..ef8e4d098 100644 --- a/library/core/src/ascii.rs +++ b/library/core/src/ascii.rs @@ -9,10 +9,14 @@ #![stable(feature = "core_ascii", since = "1.26.0")] +use crate::escape; use crate::fmt; use crate::iter::FusedIterator; -use crate::ops::Range; -use crate::str::from_utf8_unchecked; +use crate::num::NonZeroUsize; + +mod ascii_char; +#[unstable(feature = "ascii_char", issue = "110998")] +pub use ascii_char::AsciiChar as Char; /// An iterator over the escaped version of a byte. /// @@ -21,10 +25,7 @@ use crate::str::from_utf8_unchecked; #[must_use = "iterators are lazy and do nothing unless consumed"] #[stable(feature = "rust1", since = "1.0.0")] #[derive(Clone)] -pub struct EscapeDefault { - range: Range<u8>, - data: [u8; 4], -} +pub struct EscapeDefault(escape::EscapeIterInner<4>); /// Returns an iterator that produces an escaped version of a `u8`. /// @@ -90,21 +91,9 @@ pub struct EscapeDefault { /// ``` #[stable(feature = "rust1", since = "1.0.0")] pub fn escape_default(c: u8) -> EscapeDefault { - let (data, len) = match c { - b'\t' => ([b'\\', b't', 0, 0], 2), - b'\r' => ([b'\\', b'r', 0, 0], 2), - b'\n' => ([b'\\', b'n', 0, 0], 2), - b'\\' => ([b'\\', b'\\', 0, 0], 2), - b'\'' => ([b'\\', b'\'', 0, 0], 2), - b'"' => ([b'\\', b'"', 0, 0], 2), - b'\x20'..=b'\x7e' => ([c, 0, 0, 0], 1), - _ => { - let hex_digits: &[u8; 16] = b"0123456789abcdef"; - ([b'\\', b'x', hex_digits[(c >> 4) as usize], hex_digits[(c & 0xf) as usize]], 4) - } - }; - - return EscapeDefault { range: 0..len, data }; + let mut data = [Char::Null; 4]; + let range = escape::escape_ascii_into(&mut data, c); + EscapeDefault(escape::EscapeIterInner::new(data, range)) } #[stable(feature = "rust1", since = "1.0.0")] @@ -113,33 +102,59 @@ impl Iterator for EscapeDefault { #[inline] fn next(&mut self) -> Option<u8> { - self.range.next().map(|i| self.data[i as usize]) + self.0.next() } + + #[inline] fn size_hint(&self) -> (usize, Option<usize>) { - self.range.size_hint() + let n = self.0.len(); + (n, Some(n)) } + + #[inline] + fn count(self) -> usize { + self.0.len() + } + + #[inline] fn last(mut self) -> Option<u8> { - self.next_back() + self.0.next_back() + } + + #[inline] + fn advance_by(&mut self, n: usize) -> Result<(), NonZeroUsize> { + self.0.advance_by(n) } } + #[stable(feature = "rust1", since = "1.0.0")] impl DoubleEndedIterator for EscapeDefault { + #[inline] fn next_back(&mut self) -> Option<u8> { - self.range.next_back().map(|i| self.data[i as usize]) + self.0.next_back() + } + + #[inline] + fn advance_back_by(&mut self, n: usize) -> Result<(), NonZeroUsize> { + self.0.advance_back_by(n) } } + #[stable(feature = "rust1", since = "1.0.0")] -impl ExactSizeIterator for EscapeDefault {} +impl ExactSizeIterator for EscapeDefault { + #[inline] + fn len(&self) -> usize { + self.0.len() + } +} + #[stable(feature = "fused", since = "1.26.0")] impl FusedIterator for EscapeDefault {} #[stable(feature = "ascii_escape_display", since = "1.39.0")] impl fmt::Display for EscapeDefault { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - // SAFETY: ok because `escape_default` created only valid utf-8 data - f.write_str(unsafe { - from_utf8_unchecked(&self.data[(self.range.start as usize)..(self.range.end as usize)]) - }) + f.write_str(self.0.as_str()) } } diff --git a/library/core/src/ascii/ascii_char.rs b/library/core/src/ascii/ascii_char.rs new file mode 100644 index 000000000..f093a0990 --- /dev/null +++ b/library/core/src/ascii/ascii_char.rs @@ -0,0 +1,565 @@ +//! This uses the name `AsciiChar`, even though it's not exposed that way right now, +//! because it avoids a whole bunch of "are you sure you didn't mean `char`?" +//! suggestions from rustc if you get anything slightly wrong in here, and overall +//! helps with clarity as we're also referring to `char` intentionally in here. + +use crate::fmt; +use crate::mem::transmute; + +/// One of the 128 Unicode characters from U+0000 through U+007F, +/// often known as the [ASCII] subset. +/// +/// Officially, this is the first [block] in Unicode, _Basic Latin_. +/// For details, see the [*C0 Controls and Basic Latin*][chart] code chart. +/// +/// This block was based on older 7-bit character code standards such as +/// ANSI X3.4-1977, ISO 646-1973, and [NIST FIPS 1-2]. +/// +/// # When to use this +/// +/// The main advantage of this subset is that it's always valid UTF-8. As such, +/// the `&[ascii::Char]` -> `&str` conversion function (as well as other related +/// ones) are O(1): *no* runtime checks are needed. +/// +/// If you're consuming strings, you should usually handle Unicode and thus +/// accept `str`s, not limit yourself to `ascii::Char`s. +/// +/// However, certain formats are intentionally designed to produce ASCII-only +/// output in order to be 8-bit-clean. In those cases, it can be simpler and +/// faster to generate `ascii::Char`s instead of dealing with the variable width +/// properties of general UTF-8 encoded strings, while still allowing the result +/// to be used freely with other Rust things that deal in general `str`s. +/// +/// For example, a UUID library might offer a way to produce the string +/// representation of a UUID as an `[ascii::Char; 36]` to avoid memory +/// allocation yet still allow it to be used as UTF-8 via `as_str` without +/// paying for validation (or needing `unsafe` code) the way it would if it +/// were provided as a `[u8; 36]`. +/// +/// # Layout +/// +/// This type is guaranteed to have a size and alignment of 1 byte. +/// +/// # Names +/// +/// The variants on this type are [Unicode names][NamesList] of the characters +/// in upper camel case, with a few tweaks: +/// - For `<control>` characters, the primary alias name is used. +/// - `LATIN` is dropped, as this block has no non-latin letters. +/// - `LETTER` is dropped, as `CAPITAL`/`SMALL` suffices in this block. +/// - `DIGIT`s use a single digit rather than writing out `ZERO`, `ONE`, etc. +/// +/// [ASCII]: https://www.unicode.org/glossary/index.html#ASCII +/// [block]: https://www.unicode.org/glossary/index.html#block +/// [chart]: https://www.unicode.org/charts/PDF/U0000.pdf +/// [NIST FIPS 1-2]: https://nvlpubs.nist.gov/nistpubs/Legacy/FIPS/fipspub1-2-1977.pdf +/// [NamesList]: https://www.unicode.org/Public/15.0.0/ucd/NamesList.txt +#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)] +#[unstable(feature = "ascii_char", issue = "110998")] +#[repr(u8)] +pub enum AsciiChar { + /// U+0000 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Null = 0, + /// U+0001 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + StartOfHeading = 1, + /// U+0002 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + StartOfText = 2, + /// U+0003 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + EndOfText = 3, + /// U+0004 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + EndOfTransmission = 4, + /// U+0005 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Enquiry = 5, + /// U+0006 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Acknowledge = 6, + /// U+0007 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Bell = 7, + /// U+0008 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Backspace = 8, + /// U+0009 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CharacterTabulation = 9, + /// U+000A + #[unstable(feature = "ascii_char_variants", issue = "110998")] + LineFeed = 10, + /// U+000B + #[unstable(feature = "ascii_char_variants", issue = "110998")] + LineTabulation = 11, + /// U+000C + #[unstable(feature = "ascii_char_variants", issue = "110998")] + FormFeed = 12, + /// U+000D + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CarriageReturn = 13, + /// U+000E + #[unstable(feature = "ascii_char_variants", issue = "110998")] + ShiftOut = 14, + /// U+000F + #[unstable(feature = "ascii_char_variants", issue = "110998")] + ShiftIn = 15, + /// U+0010 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + DataLinkEscape = 16, + /// U+0011 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + DeviceControlOne = 17, + /// U+0012 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + DeviceControlTwo = 18, + /// U+0013 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + DeviceControlThree = 19, + /// U+0014 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + DeviceControlFour = 20, + /// U+0015 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + NegativeAcknowledge = 21, + /// U+0016 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SynchronousIdle = 22, + /// U+0017 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + EndOfTransmissionBlock = 23, + /// U+0018 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Cancel = 24, + /// U+0019 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + EndOfMedium = 25, + /// U+001A + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Substitute = 26, + /// U+001B + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Escape = 27, + /// U+001C + #[unstable(feature = "ascii_char_variants", issue = "110998")] + InformationSeparatorFour = 28, + /// U+001D + #[unstable(feature = "ascii_char_variants", issue = "110998")] + InformationSeparatorThree = 29, + /// U+001E + #[unstable(feature = "ascii_char_variants", issue = "110998")] + InformationSeparatorTwo = 30, + /// U+001F + #[unstable(feature = "ascii_char_variants", issue = "110998")] + InformationSeparatorOne = 31, + /// U+0020 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Space = 32, + /// U+0021 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + ExclamationMark = 33, + /// U+0022 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + QuotationMark = 34, + /// U+0023 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + NumberSign = 35, + /// U+0024 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + DollarSign = 36, + /// U+0025 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + PercentSign = 37, + /// U+0026 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Ampersand = 38, + /// U+0027 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Apostrophe = 39, + /// U+0028 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + LeftParenthesis = 40, + /// U+0029 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + RightParenthesis = 41, + /// U+002A + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Asterisk = 42, + /// U+002B + #[unstable(feature = "ascii_char_variants", issue = "110998")] + PlusSign = 43, + /// U+002C + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Comma = 44, + /// U+002D + #[unstable(feature = "ascii_char_variants", issue = "110998")] + HyphenMinus = 45, + /// U+002E + #[unstable(feature = "ascii_char_variants", issue = "110998")] + FullStop = 46, + /// U+002F + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Solidus = 47, + /// U+0030 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Digit0 = 48, + /// U+0031 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Digit1 = 49, + /// U+0032 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Digit2 = 50, + /// U+0033 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Digit3 = 51, + /// U+0034 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Digit4 = 52, + /// U+0035 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Digit5 = 53, + /// U+0036 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Digit6 = 54, + /// U+0037 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Digit7 = 55, + /// U+0038 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Digit8 = 56, + /// U+0039 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Digit9 = 57, + /// U+003A + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Colon = 58, + /// U+003B + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Semicolon = 59, + /// U+003C + #[unstable(feature = "ascii_char_variants", issue = "110998")] + LessThanSign = 60, + /// U+003D + #[unstable(feature = "ascii_char_variants", issue = "110998")] + EqualsSign = 61, + /// U+003E + #[unstable(feature = "ascii_char_variants", issue = "110998")] + GreaterThanSign = 62, + /// U+003F + #[unstable(feature = "ascii_char_variants", issue = "110998")] + QuestionMark = 63, + /// U+0040 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CommercialAt = 64, + /// U+0041 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalA = 65, + /// U+0042 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalB = 66, + /// U+0043 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalC = 67, + /// U+0044 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalD = 68, + /// U+0045 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalE = 69, + /// U+0046 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalF = 70, + /// U+0047 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalG = 71, + /// U+0048 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalH = 72, + /// U+0049 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalI = 73, + /// U+004A + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalJ = 74, + /// U+004B + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalK = 75, + /// U+004C + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalL = 76, + /// U+004D + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalM = 77, + /// U+004E + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalN = 78, + /// U+004F + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalO = 79, + /// U+0050 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalP = 80, + /// U+0051 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalQ = 81, + /// U+0052 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalR = 82, + /// U+0053 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalS = 83, + /// U+0054 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalT = 84, + /// U+0055 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalU = 85, + /// U+0056 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalV = 86, + /// U+0057 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalW = 87, + /// U+0058 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalX = 88, + /// U+0059 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalY = 89, + /// U+005A + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CapitalZ = 90, + /// U+005B + #[unstable(feature = "ascii_char_variants", issue = "110998")] + LeftSquareBracket = 91, + /// U+005C + #[unstable(feature = "ascii_char_variants", issue = "110998")] + ReverseSolidus = 92, + /// U+005D + #[unstable(feature = "ascii_char_variants", issue = "110998")] + RightSquareBracket = 93, + /// U+005E + #[unstable(feature = "ascii_char_variants", issue = "110998")] + CircumflexAccent = 94, + /// U+005F + #[unstable(feature = "ascii_char_variants", issue = "110998")] + LowLine = 95, + /// U+0060 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + GraveAccent = 96, + /// U+0061 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallA = 97, + /// U+0062 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallB = 98, + /// U+0063 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallC = 99, + /// U+0064 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallD = 100, + /// U+0065 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallE = 101, + /// U+0066 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallF = 102, + /// U+0067 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallG = 103, + /// U+0068 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallH = 104, + /// U+0069 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallI = 105, + /// U+006A + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallJ = 106, + /// U+006B + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallK = 107, + /// U+006C + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallL = 108, + /// U+006D + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallM = 109, + /// U+006E + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallN = 110, + /// U+006F + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallO = 111, + /// U+0070 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallP = 112, + /// U+0071 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallQ = 113, + /// U+0072 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallR = 114, + /// U+0073 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallS = 115, + /// U+0074 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallT = 116, + /// U+0075 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallU = 117, + /// U+0076 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallV = 118, + /// U+0077 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallW = 119, + /// U+0078 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallX = 120, + /// U+0079 + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallY = 121, + /// U+007A + #[unstable(feature = "ascii_char_variants", issue = "110998")] + SmallZ = 122, + /// U+007B + #[unstable(feature = "ascii_char_variants", issue = "110998")] + LeftCurlyBracket = 123, + /// U+007C + #[unstable(feature = "ascii_char_variants", issue = "110998")] + VerticalLine = 124, + /// U+007D + #[unstable(feature = "ascii_char_variants", issue = "110998")] + RightCurlyBracket = 125, + /// U+007E + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Tilde = 126, + /// U+007F + #[unstable(feature = "ascii_char_variants", issue = "110998")] + Delete = 127, +} + +impl AsciiChar { + /// Creates an ascii character from the byte `b`, + /// or returns `None` if it's too large. + #[unstable(feature = "ascii_char", issue = "110998")] + #[inline] + pub const fn from_u8(b: u8) -> Option<Self> { + if b <= 127 { + // SAFETY: Just checked that `b` is in-range + Some(unsafe { Self::from_u8_unchecked(b) }) + } else { + None + } + } + + /// Creates an ASCII character from the byte `b`, + /// without checking whether it's valid. + /// + /// # Safety + /// + /// `b` must be in `0..=127`, or else this is UB. + #[unstable(feature = "ascii_char", issue = "110998")] + #[inline] + pub const unsafe fn from_u8_unchecked(b: u8) -> Self { + // SAFETY: Our safety precondition is that `b` is in-range. + unsafe { transmute(b) } + } + + /// When passed the *number* `0`, `1`, …, `9`, returns the *character* + /// `'0'`, `'1'`, …, `'9'` respectively. + /// + /// If `d >= 10`, returns `None`. + #[unstable(feature = "ascii_char", issue = "110998")] + #[inline] + pub const fn digit(d: u8) -> Option<Self> { + if d < 10 { + // SAFETY: Just checked it's in-range. + Some(unsafe { Self::digit_unchecked(d) }) + } else { + None + } + } + + /// When passed the *number* `0`, `1`, …, `9`, returns the *character* + /// `'0'`, `'1'`, …, `'9'` respectively, without checking that it's in-range. + /// + /// # Safety + /// + /// This is immediate UB if called with `d > 64`. + /// + /// If `d >= 10` and `d <= 64`, this is allowed to return any value or panic. + /// Notably, it should not be expected to return hex digits, or any other + /// reasonable extension of the decimal digits. + /// + /// (This lose safety condition is intended to simplify soundness proofs + /// when writing code using this method, since the implementation doesn't + /// need something really specific, not to make those other arguments do + /// something useful. It might be tightened before stabilization.) + #[unstable(feature = "ascii_char", issue = "110998")] + #[inline] + pub const unsafe fn digit_unchecked(d: u8) -> Self { + debug_assert!(d < 10); + + // SAFETY: `'0'` through `'9'` are U+00030 through U+0039, + // so because `d` must be 64 or less the addition can return at most + // 112 (0x70), which doesn't overflow and is within the ASCII range. + unsafe { + let byte = b'0'.unchecked_add(d); + Self::from_u8_unchecked(byte) + } + } + + /// Gets this ASCII character as a byte. + #[unstable(feature = "ascii_char", issue = "110998")] + #[inline] + pub const fn as_u8(self) -> u8 { + self as u8 + } + + /// Gets this ASCII character as a `char` Unicode Scalar Value. + #[unstable(feature = "ascii_char", issue = "110998")] + #[inline] + pub const fn as_char(self) -> char { + self as u8 as char + } + + /// Views this ASCII character as a one-code-unit UTF-8 `str`. + #[unstable(feature = "ascii_char", issue = "110998")] + #[inline] + pub const fn as_str(&self) -> &str { + crate::slice::from_ref(self).as_str() + } +} + +impl [AsciiChar] { + /// Views this slice of ASCII characters as a UTF-8 `str`. + #[unstable(feature = "ascii_char", issue = "110998")] + #[inline] + pub const fn as_str(&self) -> &str { + let ascii_ptr: *const Self = self; + let str_ptr = ascii_ptr as *const str; + // SAFETY: Each ASCII codepoint in UTF-8 is encoded as one single-byte + // code unit having the same value as the ASCII byte. + unsafe { &*str_ptr } + } + + /// Views this slice of ASCII characters as a slice of `u8` bytes. + #[unstable(feature = "ascii_char", issue = "110998")] + #[inline] + pub const fn as_bytes(&self) -> &[u8] { + self.as_str().as_bytes() + } +} + +#[unstable(feature = "ascii_char", issue = "110998")] +impl fmt::Display for AsciiChar { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + <str as fmt::Display>::fmt(self.as_str(), f) + } +} diff --git a/library/core/src/bool.rs b/library/core/src/bool.rs index db1c505ba..03cdff9b1 100644 --- a/library/core/src/bool.rs +++ b/library/core/src/bool.rs @@ -1,7 +1,5 @@ //! impl bool {} -use crate::marker::Destruct; - impl bool { /// Returns `Some(t)` if the `bool` is [`true`](../std/keyword.true.html), /// or `None` otherwise. @@ -31,12 +29,8 @@ impl bool { /// assert_eq!(a, 2); /// ``` #[stable(feature = "bool_to_option", since = "1.62.0")] - #[rustc_const_unstable(feature = "const_bool_to_option", issue = "91917")] #[inline] - pub const fn then_some<T>(self, t: T) -> Option<T> - where - T: ~const Destruct, - { + pub fn then_some<T>(self, t: T) -> Option<T> { if self { Some(t) } else { None } } @@ -61,13 +55,8 @@ impl bool { /// assert_eq!(a, 1); /// ``` #[stable(feature = "lazy_bool_to_option", since = "1.50.0")] - #[rustc_const_unstable(feature = "const_bool_to_option", issue = "91917")] #[inline] - pub const fn then<T, F>(self, f: F) -> Option<T> - where - F: ~const FnOnce() -> T, - F: ~const Destruct, - { + pub fn then<T, F: FnOnce() -> T>(self, f: F) -> Option<T> { if self { Some(f()) } else { None } } } diff --git a/library/core/src/borrow.rs b/library/core/src/borrow.rs index 4a8302ee4..efc9ada38 100644 --- a/library/core/src/borrow.rs +++ b/library/core/src/borrow.rs @@ -154,7 +154,6 @@ /// [`String`]: ../../std/string/struct.String.html #[stable(feature = "rust1", since = "1.0.0")] #[rustc_diagnostic_item = "Borrow"] -#[const_trait] pub trait Borrow<Borrowed: ?Sized> { /// Immutably borrows from an owned value. /// @@ -185,7 +184,6 @@ pub trait Borrow<Borrowed: ?Sized> { /// an underlying type by providing a mutable reference. See [`Borrow<T>`] /// for more information on borrowing as another type. #[stable(feature = "rust1", since = "1.0.0")] -#[const_trait] pub trait BorrowMut<Borrowed: ?Sized>: Borrow<Borrowed> { /// Mutably borrows from an owned value. /// @@ -207,8 +205,7 @@ pub trait BorrowMut<Borrowed: ?Sized>: Borrow<Borrowed> { } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_borrow", issue = "91522")] -impl<T: ?Sized> const Borrow<T> for T { +impl<T: ?Sized> Borrow<T> for T { #[rustc_diagnostic_item = "noop_method_borrow"] fn borrow(&self) -> &T { self @@ -216,32 +213,28 @@ impl<T: ?Sized> const Borrow<T> for T { } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_borrow", issue = "91522")] -impl<T: ?Sized> const BorrowMut<T> for T { +impl<T: ?Sized> BorrowMut<T> for T { fn borrow_mut(&mut self) -> &mut T { self } } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_borrow", issue = "91522")] -impl<T: ?Sized> const Borrow<T> for &T { +impl<T: ?Sized> Borrow<T> for &T { fn borrow(&self) -> &T { &**self } } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_borrow", issue = "91522")] -impl<T: ?Sized> const Borrow<T> for &mut T { +impl<T: ?Sized> Borrow<T> for &mut T { fn borrow(&self) -> &T { &**self } } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_borrow", issue = "91522")] -impl<T: ?Sized> const BorrowMut<T> for &mut T { +impl<T: ?Sized> BorrowMut<T> for &mut T { fn borrow_mut(&mut self) -> &mut T { &mut **self } diff --git a/library/core/src/cell.rs b/library/core/src/cell.rs index 33d928e23..744767aae 100644 --- a/library/core/src/cell.rs +++ b/library/core/src/cell.rs @@ -115,7 +115,7 @@ //! let shared_map: Rc<RefCell<_>> = Rc::new(RefCell::new(HashMap::new())); //! // Create a new block to limit the scope of the dynamic borrow //! { -//! let mut map: RefMut<_> = shared_map.borrow_mut(); +//! let mut map: RefMut<'_, _> = shared_map.borrow_mut(); //! map.insert("africa", 92388); //! map.insert("kyoto", 11837); //! map.insert("piccadilly", 11826); @@ -370,8 +370,7 @@ impl<T: Ord + Copy> Ord for Cell<T> { } #[stable(feature = "cell_from", since = "1.12.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T> const From<T> for Cell<T> { +impl<T> From<T> for Cell<T> { /// Creates a new `Cell<T>` containing the given value. fn from(t: T) -> Cell<T> { Cell::new(t) @@ -1318,8 +1317,7 @@ impl<T: ?Sized + Ord> Ord for RefCell<T> { } #[stable(feature = "cell_from", since = "1.12.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T> const From<T> for RefCell<T> { +impl<T> From<T> for RefCell<T> { /// Creates a new `RefCell<T>` containing the given value. fn from(t: T) -> RefCell<T> { RefCell::new(t) @@ -1437,8 +1435,8 @@ impl<'b, T: ?Sized> Ref<'b, T> { /// use std::cell::{RefCell, Ref}; /// /// let c = RefCell::new((5, 'b')); - /// let b1: Ref<(u32, char)> = c.borrow(); - /// let b2: Ref<u32> = Ref::map(b1, |t| &t.0); + /// let b1: Ref<'_, (u32, char)> = c.borrow(); + /// let b2: Ref<'_, u32> = Ref::map(b1, |t| &t.0); /// assert_eq!(*b2, 5) /// ``` #[stable(feature = "cell_map", since = "1.8.0")] @@ -1466,8 +1464,8 @@ impl<'b, T: ?Sized> Ref<'b, T> { /// use std::cell::{RefCell, Ref}; /// /// let c = RefCell::new(vec![1, 2, 3]); - /// let b1: Ref<Vec<u32>> = c.borrow(); - /// let b2: Result<Ref<u32>, _> = Ref::filter_map(b1, |v| v.get(1)); + /// let b1: Ref<'_, Vec<u32>> = c.borrow(); + /// let b2: Result<Ref<'_, u32>, _> = Ref::filter_map(b1, |v| v.get(1)); /// assert_eq!(*b2.unwrap(), 2); /// ``` #[stable(feature = "cell_filter_map", since = "1.63.0")] @@ -1579,8 +1577,8 @@ impl<'b, T: ?Sized> RefMut<'b, T> { /// /// let c = RefCell::new((5, 'b')); /// { - /// let b1: RefMut<(u32, char)> = c.borrow_mut(); - /// let mut b2: RefMut<u32> = RefMut::map(b1, |t| &mut t.0); + /// let b1: RefMut<'_, (u32, char)> = c.borrow_mut(); + /// let mut b2: RefMut<'_, u32> = RefMut::map(b1, |t| &mut t.0); /// assert_eq!(*b2, 5); /// *b2 = 42; /// } @@ -1614,8 +1612,8 @@ impl<'b, T: ?Sized> RefMut<'b, T> { /// let c = RefCell::new(vec![1, 2, 3]); /// /// { - /// let b1: RefMut<Vec<u32>> = c.borrow_mut(); - /// let mut b2: Result<RefMut<u32>, _> = RefMut::filter_map(b1, |v| v.get_mut(1)); + /// let b1: RefMut<'_, Vec<u32>> = c.borrow_mut(); + /// let mut b2: Result<RefMut<'_, u32>, _> = RefMut::filter_map(b1, |v| v.get_mut(1)); /// /// if let Ok(mut b2) = b2 { /// *b2 += 2; @@ -2032,6 +2030,27 @@ impl<T> UnsafeCell<T> { } impl<T: ?Sized> UnsafeCell<T> { + /// Converts from `&mut T` to `&mut UnsafeCell<T>`. + /// + /// # Examples + /// + /// ``` + /// # #![feature(unsafe_cell_from_mut)] + /// use std::cell::UnsafeCell; + /// + /// let mut val = 42; + /// let uc = UnsafeCell::from_mut(&mut val); + /// + /// *uc.get_mut() -= 1; + /// assert_eq!(*uc.get_mut(), 41); + /// ``` + #[inline(always)] + #[unstable(feature = "unsafe_cell_from_mut", issue = "111645")] + pub const fn from_mut(value: &mut T) -> &mut UnsafeCell<T> { + // SAFETY: `UnsafeCell<T>` has the same memory layout as `T` due to #[repr(transparent)]. + unsafe { &mut *(value as *mut T as *mut UnsafeCell<T>) } + } + /// Gets a mutable pointer to the wrapped value. /// /// This can be cast to a pointer of any kind. @@ -2102,6 +2121,8 @@ impl<T: ?Sized> UnsafeCell<T> { /// /// let m = MaybeUninit::<UnsafeCell<i32>>::uninit(); /// unsafe { UnsafeCell::raw_get(m.as_ptr()).write(5); } + /// // avoid below which references to uninitialized data + /// // unsafe { UnsafeCell::get(&*m.as_ptr()).write(5); } /// let uc = unsafe { m.assume_init() }; /// /// assert_eq!(uc.into_inner(), 5); @@ -2126,8 +2147,7 @@ impl<T: Default> Default for UnsafeCell<T> { } #[stable(feature = "cell_from", since = "1.12.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T> const From<T> for UnsafeCell<T> { +impl<T> From<T> for UnsafeCell<T> { /// Creates a new `UnsafeCell<T>` containing the given value. fn from(t: T) -> UnsafeCell<T> { UnsafeCell::new(t) @@ -2226,8 +2246,7 @@ impl<T: Default> Default for SyncUnsafeCell<T> { } #[unstable(feature = "sync_unsafe_cell", issue = "95439")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T> const From<T> for SyncUnsafeCell<T> { +impl<T> From<T> for SyncUnsafeCell<T> { /// Creates a new `SyncUnsafeCell<T>` containing the given value. fn from(t: T) -> SyncUnsafeCell<T> { SyncUnsafeCell::new(t) diff --git a/library/core/src/cell/lazy.rs b/library/core/src/cell/lazy.rs index 44adcfa1a..1b213f6a2 100644 --- a/library/core/src/cell/lazy.rs +++ b/library/core/src/cell/lazy.rs @@ -63,6 +63,34 @@ impl<T, F: FnOnce() -> T> LazyCell<T, F> { LazyCell { state: UnsafeCell::new(State::Uninit(f)) } } + /// Consumes this `LazyCell` returning the stored value. + /// + /// Returns `Ok(value)` if `Lazy` is initialized and `Err(f)` otherwise. + /// + /// # Examples + /// + /// ``` + /// #![feature(lazy_cell)] + /// #![feature(lazy_cell_consume)] + /// + /// use std::cell::LazyCell; + /// + /// let hello = "Hello, World!".to_string(); + /// + /// let lazy = LazyCell::new(|| hello.to_uppercase()); + /// + /// assert_eq!(&*lazy, "HELLO, WORLD!"); + /// assert_eq!(LazyCell::into_inner(lazy).ok(), Some("HELLO, WORLD!".to_string())); + /// ``` + #[unstable(feature = "lazy_cell_consume", issue = "109736")] + pub fn into_inner(this: Self) -> Result<T, F> { + match this.state.into_inner() { + State::Init(data) => Ok(data), + State::Uninit(f) => Err(f), + State::Poisoned => panic!("LazyCell instance has previously been poisoned"), + } + } + /// Forces the evaluation of this lazy value and returns a reference to /// the result. /// diff --git a/library/core/src/cell/once.rs b/library/core/src/cell/once.rs index f7cd3ec5f..5f06a7b07 100644 --- a/library/core/src/cell/once.rs +++ b/library/core/src/cell/once.rs @@ -284,8 +284,7 @@ impl<T: PartialEq> PartialEq for OnceCell<T> { impl<T: Eq> Eq for OnceCell<T> {} #[stable(feature = "once_cell", since = "1.70.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T> const From<T> for OnceCell<T> { +impl<T> From<T> for OnceCell<T> { /// Creates a new `OnceCell<T>` which already contains the given `value`. #[inline] fn from(value: T) -> Self { diff --git a/library/core/src/char/convert.rs b/library/core/src/char/convert.rs index 136bbcb8b..b84e4b35b 100644 --- a/library/core/src/char/convert.rs +++ b/library/core/src/char/convert.rs @@ -27,8 +27,7 @@ pub(super) const unsafe fn from_u32_unchecked(i: u32) -> char { } #[stable(feature = "char_convert", since = "1.13.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl const From<char> for u32 { +impl From<char> for u32 { /// Converts a [`char`] into a [`u32`]. /// /// # Examples @@ -47,8 +46,7 @@ impl const From<char> for u32 { } #[stable(feature = "more_char_conversions", since = "1.51.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl const From<char> for u64 { +impl From<char> for u64 { /// Converts a [`char`] into a [`u64`]. /// /// # Examples @@ -69,8 +67,7 @@ impl const From<char> for u64 { } #[stable(feature = "more_char_conversions", since = "1.51.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl const From<char> for u128 { +impl From<char> for u128 { /// Converts a [`char`] into a [`u128`]. /// /// # Examples @@ -123,8 +120,7 @@ impl TryFrom<char> for u8 { /// for a superset of Windows-1252 that fills the remaining blanks with corresponding /// C0 and C1 control codes. #[stable(feature = "char_convert", since = "1.13.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl const From<u8> for char { +impl From<u8> for char { /// Converts a [`u8`] into a [`char`]. /// /// # Examples diff --git a/library/core/src/char/methods.rs b/library/core/src/char/methods.rs index 9bc97ea0b..515b8d20e 100644 --- a/library/core/src/char/methods.rs +++ b/library/core/src/char/methods.rs @@ -1,5 +1,6 @@ //! impl char {} +use crate::ascii; use crate::slice; use crate::str::from_utf8_unchecked_mut; use crate::unicode::printable::is_printable; @@ -380,20 +381,7 @@ impl char { #[stable(feature = "rust1", since = "1.0.0")] #[inline] pub fn escape_unicode(self) -> EscapeUnicode { - let c = self as u32; - - // or-ing 1 ensures that for c==0 the code computes that one - // digit should be printed and (which is the same) avoids the - // (31 - 32) underflow - let msb = 31 - (c | 1).leading_zeros(); - - // the index of the most significant hex digit - let ms_hex_digit = msb / 4; - EscapeUnicode { - c: self, - state: EscapeUnicodeState::Backslash, - hex_digit_idx: ms_hex_digit as usize, - } + EscapeUnicode::new(self) } /// An extended version of `escape_debug` that optionally permits escaping @@ -403,21 +391,20 @@ impl char { /// characters, and double quotes in strings. #[inline] pub(crate) fn escape_debug_ext(self, args: EscapeDebugExtArgs) -> EscapeDebug { - let init_state = match self { - '\0' => EscapeDefaultState::Backslash('0'), - '\t' => EscapeDefaultState::Backslash('t'), - '\r' => EscapeDefaultState::Backslash('r'), - '\n' => EscapeDefaultState::Backslash('n'), - '\\' => EscapeDefaultState::Backslash(self), - '"' if args.escape_double_quote => EscapeDefaultState::Backslash(self), - '\'' if args.escape_single_quote => EscapeDefaultState::Backslash(self), + match self { + '\0' => EscapeDebug::backslash(ascii::Char::Digit0), + '\t' => EscapeDebug::backslash(ascii::Char::SmallT), + '\r' => EscapeDebug::backslash(ascii::Char::SmallR), + '\n' => EscapeDebug::backslash(ascii::Char::SmallN), + '\\' => EscapeDebug::backslash(ascii::Char::ReverseSolidus), + '\"' if args.escape_double_quote => EscapeDebug::backslash(ascii::Char::QuotationMark), + '\'' if args.escape_single_quote => EscapeDebug::backslash(ascii::Char::Apostrophe), _ if args.escape_grapheme_extended && self.is_grapheme_extended() => { - EscapeDefaultState::Unicode(self.escape_unicode()) + EscapeDebug::from_unicode(self.escape_unicode()) } - _ if is_printable(self) => EscapeDefaultState::Char(self), - _ => EscapeDefaultState::Unicode(self.escape_unicode()), - }; - EscapeDebug(EscapeDefault { state: init_state }) + _ if is_printable(self) => EscapeDebug::printable(self), + _ => EscapeDebug::from_unicode(self.escape_unicode()), + } } /// Returns an iterator that yields the literal escape code of a character @@ -515,15 +502,14 @@ impl char { #[stable(feature = "rust1", since = "1.0.0")] #[inline] pub fn escape_default(self) -> EscapeDefault { - let init_state = match self { - '\t' => EscapeDefaultState::Backslash('t'), - '\r' => EscapeDefaultState::Backslash('r'), - '\n' => EscapeDefaultState::Backslash('n'), - '\\' | '\'' | '"' => EscapeDefaultState::Backslash(self), - '\x20'..='\x7e' => EscapeDefaultState::Char(self), - _ => EscapeDefaultState::Unicode(self.escape_unicode()), - }; - EscapeDefault { state: init_state } + match self { + '\t' => EscapeDefault::backslash(ascii::Char::SmallT), + '\r' => EscapeDefault::backslash(ascii::Char::SmallR), + '\n' => EscapeDefault::backslash(ascii::Char::SmallN), + '\\' | '\'' | '"' => EscapeDefault::backslash(self.as_ascii().unwrap()), + '\x20'..='\x7e' => EscapeDefault::printable(self.as_ascii().unwrap()), + _ => EscapeDefault::from_unicode(self.escape_unicode()), + } } /// Returns the number of bytes this `char` would need if encoded in UTF-8. @@ -1116,6 +1102,24 @@ impl char { *self as u32 <= 0x7F } + /// Returns `Some` if the value is within the ASCII range, + /// or `None` if it's not. + /// + /// This is preferred to [`Self::is_ascii`] when you're passing the value + /// along to something else that can take [`ascii::Char`] rather than + /// needing to check again for itself whether the value is in ASCII. + #[must_use] + #[unstable(feature = "ascii_char", issue = "110998")] + #[inline] + pub const fn as_ascii(&self) -> Option<ascii::Char> { + if self.is_ascii() { + // SAFETY: Just checked that this is ASCII. + Some(unsafe { ascii::Char::from_u8_unchecked(*self as u8) }) + } else { + None + } + } + /// Makes a copy of the value in its ASCII upper case equivalent. /// /// ASCII letters 'a' to 'z' are mapped to 'A' to 'Z', diff --git a/library/core/src/char/mod.rs b/library/core/src/char/mod.rs index 8ec78e887..5c4291287 100644 --- a/library/core/src/char/mod.rs +++ b/library/core/src/char/mod.rs @@ -38,9 +38,12 @@ pub use self::methods::encode_utf16_raw; #[unstable(feature = "char_internals", reason = "exposed only for libstd", issue = "none")] pub use self::methods::encode_utf8_raw; +use crate::ascii; use crate::error::Error; +use crate::escape; use crate::fmt::{self, Write}; use crate::iter::FusedIterator; +use crate::num::NonZeroUsize; pub(crate) use self::methods::EscapeDebugExtArgs; @@ -146,86 +149,44 @@ pub const fn from_digit(num: u32, radix: u32) -> Option<char> { /// [`escape_unicode`]: char::escape_unicode #[derive(Clone, Debug)] #[stable(feature = "rust1", since = "1.0.0")] -pub struct EscapeUnicode { - c: char, - state: EscapeUnicodeState, - - // The index of the next hex digit to be printed (0 if none), - // i.e., the number of remaining hex digits to be printed; - // increasing from the least significant digit: 0x543210 - hex_digit_idx: usize, -} +pub struct EscapeUnicode(escape::EscapeIterInner<10>); -// The enum values are ordered so that their representation is the -// same as the remaining length (besides the hexadecimal digits). This -// likely makes `len()` a single load from memory) and inline-worth. -#[derive(Clone, Debug)] -enum EscapeUnicodeState { - Done, - RightBrace, - Value, - LeftBrace, - Type, - Backslash, +impl EscapeUnicode { + fn new(chr: char) -> Self { + let mut data = [ascii::Char::Null; 10]; + let range = escape::escape_unicode_into(&mut data, chr); + Self(escape::EscapeIterInner::new(data, range)) + } } #[stable(feature = "rust1", since = "1.0.0")] impl Iterator for EscapeUnicode { type Item = char; + #[inline] fn next(&mut self) -> Option<char> { - match self.state { - EscapeUnicodeState::Backslash => { - self.state = EscapeUnicodeState::Type; - Some('\\') - } - EscapeUnicodeState::Type => { - self.state = EscapeUnicodeState::LeftBrace; - Some('u') - } - EscapeUnicodeState::LeftBrace => { - self.state = EscapeUnicodeState::Value; - Some('{') - } - EscapeUnicodeState::Value => { - let hex_digit = ((self.c as u32) >> (self.hex_digit_idx * 4)) & 0xf; - let c = char::from_digit(hex_digit, 16).unwrap(); - if self.hex_digit_idx == 0 { - self.state = EscapeUnicodeState::RightBrace; - } else { - self.hex_digit_idx -= 1; - } - Some(c) - } - EscapeUnicodeState::RightBrace => { - self.state = EscapeUnicodeState::Done; - Some('}') - } - EscapeUnicodeState::Done => None, - } + self.0.next().map(char::from) } #[inline] fn size_hint(&self) -> (usize, Option<usize>) { - let n = self.len(); + let n = self.0.len(); (n, Some(n)) } #[inline] fn count(self) -> usize { - self.len() + self.0.len() } - fn last(self) -> Option<char> { - match self.state { - EscapeUnicodeState::Done => None, + #[inline] + fn last(mut self) -> Option<char> { + self.0.next_back().map(char::from) + } - EscapeUnicodeState::RightBrace - | EscapeUnicodeState::Value - | EscapeUnicodeState::LeftBrace - | EscapeUnicodeState::Type - | EscapeUnicodeState::Backslash => Some('}'), - } + #[inline] + fn advance_by(&mut self, n: usize) -> Result<(), NonZeroUsize> { + self.0.advance_by(n) } } @@ -233,16 +194,7 @@ impl Iterator for EscapeUnicode { impl ExactSizeIterator for EscapeUnicode { #[inline] fn len(&self) -> usize { - // The match is a single memory access with no branching - self.hex_digit_idx - + match self.state { - EscapeUnicodeState::Done => 0, - EscapeUnicodeState::RightBrace => 1, - EscapeUnicodeState::Value => 2, - EscapeUnicodeState::LeftBrace => 3, - EscapeUnicodeState::Type => 4, - EscapeUnicodeState::Backslash => 5, - } + self.0.len() } } @@ -252,10 +204,7 @@ impl FusedIterator for EscapeUnicode {} #[stable(feature = "char_struct_display", since = "1.16.0")] impl fmt::Display for EscapeUnicode { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - for c in self.clone() { - f.write_char(c)?; - } - Ok(()) + f.write_str(self.0.as_str()) } } @@ -267,90 +216,60 @@ impl fmt::Display for EscapeUnicode { /// [`escape_default`]: char::escape_default #[derive(Clone, Debug)] #[stable(feature = "rust1", since = "1.0.0")] -pub struct EscapeDefault { - state: EscapeDefaultState, -} +pub struct EscapeDefault(escape::EscapeIterInner<10>); -#[derive(Clone, Debug)] -enum EscapeDefaultState { - Done, - Char(char), - Backslash(char), - Unicode(EscapeUnicode), +impl EscapeDefault { + fn printable(chr: ascii::Char) -> Self { + let data = [chr]; + Self(escape::EscapeIterInner::from_array(data)) + } + + fn backslash(chr: ascii::Char) -> Self { + let data = [ascii::Char::ReverseSolidus, chr]; + Self(escape::EscapeIterInner::from_array(data)) + } + + fn from_unicode(esc: EscapeUnicode) -> Self { + Self(esc.0) + } } #[stable(feature = "rust1", since = "1.0.0")] impl Iterator for EscapeDefault { type Item = char; + #[inline] fn next(&mut self) -> Option<char> { - match self.state { - EscapeDefaultState::Backslash(c) => { - self.state = EscapeDefaultState::Char(c); - Some('\\') - } - EscapeDefaultState::Char(c) => { - self.state = EscapeDefaultState::Done; - Some(c) - } - EscapeDefaultState::Done => None, - EscapeDefaultState::Unicode(ref mut iter) => iter.next(), - } + self.0.next().map(char::from) } #[inline] fn size_hint(&self) -> (usize, Option<usize>) { - let n = self.len(); + let n = self.0.len(); (n, Some(n)) } #[inline] fn count(self) -> usize { - self.len() + self.0.len() } - fn nth(&mut self, n: usize) -> Option<char> { - match self.state { - EscapeDefaultState::Backslash(c) if n == 0 => { - self.state = EscapeDefaultState::Char(c); - Some('\\') - } - EscapeDefaultState::Backslash(c) if n == 1 => { - self.state = EscapeDefaultState::Done; - Some(c) - } - EscapeDefaultState::Backslash(_) => { - self.state = EscapeDefaultState::Done; - None - } - EscapeDefaultState::Char(c) => { - self.state = EscapeDefaultState::Done; - - if n == 0 { Some(c) } else { None } - } - EscapeDefaultState::Done => None, - EscapeDefaultState::Unicode(ref mut i) => i.nth(n), - } + #[inline] + fn last(mut self) -> Option<char> { + self.0.next_back().map(char::from) } - fn last(self) -> Option<char> { - match self.state { - EscapeDefaultState::Unicode(iter) => iter.last(), - EscapeDefaultState::Done => None, - EscapeDefaultState::Backslash(c) | EscapeDefaultState::Char(c) => Some(c), - } + #[inline] + fn advance_by(&mut self, n: usize) -> Result<(), NonZeroUsize> { + self.0.advance_by(n) } } #[stable(feature = "exact_size_escape", since = "1.11.0")] impl ExactSizeIterator for EscapeDefault { + #[inline] fn len(&self) -> usize { - match self.state { - EscapeDefaultState::Done => 0, - EscapeDefaultState::Char(_) => 1, - EscapeDefaultState::Backslash(_) => 2, - EscapeDefaultState::Unicode(ref iter) => iter.len(), - } + self.0.len() } } @@ -360,10 +279,7 @@ impl FusedIterator for EscapeDefault {} #[stable(feature = "char_struct_display", since = "1.16.0")] impl fmt::Display for EscapeDefault { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - for c in self.clone() { - f.write_char(c)?; - } - Ok(()) + f.write_str(self.0.as_str()) } } @@ -375,21 +291,74 @@ impl fmt::Display for EscapeDefault { /// [`escape_debug`]: char::escape_debug #[stable(feature = "char_escape_debug", since = "1.20.0")] #[derive(Clone, Debug)] -pub struct EscapeDebug(EscapeDefault); +pub struct EscapeDebug(EscapeDebugInner); + +#[derive(Clone, Debug)] +// Note: It’s possible to manually encode the EscapeDebugInner inside of +// EscapeIterInner (e.g. with alive=254..255 indicating that data[0..4] holds +// a char) which would likely result in a more optimised code. For now we use +// the option easier to implement. +enum EscapeDebugInner { + Bytes(escape::EscapeIterInner<10>), + Char(char), +} + +impl EscapeDebug { + fn printable(chr: char) -> Self { + Self(EscapeDebugInner::Char(chr)) + } + + fn backslash(chr: ascii::Char) -> Self { + let data = [ascii::Char::ReverseSolidus, chr]; + let iter = escape::EscapeIterInner::from_array(data); + Self(EscapeDebugInner::Bytes(iter)) + } + + fn from_unicode(esc: EscapeUnicode) -> Self { + Self(EscapeDebugInner::Bytes(esc.0)) + } + + fn clear(&mut self) { + let bytes = escape::EscapeIterInner::from_array([]); + self.0 = EscapeDebugInner::Bytes(bytes); + } +} #[stable(feature = "char_escape_debug", since = "1.20.0")] impl Iterator for EscapeDebug { type Item = char; + + #[inline] fn next(&mut self) -> Option<char> { - self.0.next() + match self.0 { + EscapeDebugInner::Bytes(ref mut bytes) => bytes.next().map(char::from), + EscapeDebugInner::Char(chr) => { + self.clear(); + Some(chr) + } + } } + fn size_hint(&self) -> (usize, Option<usize>) { - self.0.size_hint() + let n = self.len(); + (n, Some(n)) + } + + #[inline] + fn count(self) -> usize { + self.len() } } #[stable(feature = "char_escape_debug", since = "1.20.0")] -impl ExactSizeIterator for EscapeDebug {} +impl ExactSizeIterator for EscapeDebug { + fn len(&self) -> usize { + match &self.0 { + EscapeDebugInner::Bytes(bytes) => bytes.len(), + EscapeDebugInner::Char(_) => 1, + } + } +} #[stable(feature = "fused", since = "1.26.0")] impl FusedIterator for EscapeDebug {} @@ -397,7 +366,10 @@ impl FusedIterator for EscapeDebug {} #[stable(feature = "char_escape_debug", since = "1.20.0")] impl fmt::Display for EscapeDebug { fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - fmt::Display::fmt(&self.0, f) + match &self.0 { + EscapeDebugInner::Bytes(bytes) => f.write_str(bytes.as_str()), + EscapeDebugInner::Char(chr) => f.write_char(*chr), + } } } diff --git a/library/core/src/clone.rs b/library/core/src/clone.rs index 398437d9a..a6d6230d3 100644 --- a/library/core/src/clone.rs +++ b/library/core/src/clone.rs @@ -36,8 +36,6 @@ #![stable(feature = "rust1", since = "1.0.0")] -use crate::marker::Destruct; - /// A common trait for the ability to explicitly duplicate an object. /// /// Differs from [`Copy`] in that [`Copy`] is implicit and an inexpensive bit-wise copy, while @@ -106,7 +104,6 @@ use crate::marker::Destruct; #[lang = "clone"] #[rustc_diagnostic_item = "Clone"] #[rustc_trivial_field_reads] -#[const_trait] pub trait Clone: Sized { /// Returns a copy of the value. /// @@ -129,10 +126,7 @@ pub trait Clone: Sized { /// allocations. #[inline] #[stable(feature = "rust1", since = "1.0.0")] - fn clone_from(&mut self, source: &Self) - where - Self: ~const Destruct, - { + fn clone_from(&mut self, source: &Self) { *self = source.clone() } } @@ -182,8 +176,7 @@ mod impls { ($($t:ty)*) => { $( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_clone", issue = "91805")] - impl const Clone for $t { + impl Clone for $t { #[inline(always)] fn clone(&self) -> Self { *self @@ -201,8 +194,7 @@ mod impls { } #[unstable(feature = "never_type", issue = "35121")] - #[rustc_const_unstable(feature = "const_clone", issue = "91805")] - impl const Clone for ! { + impl Clone for ! { #[inline] fn clone(&self) -> Self { *self @@ -210,8 +202,7 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_clone", issue = "91805")] - impl<T: ?Sized> const Clone for *const T { + impl<T: ?Sized> Clone for *const T { #[inline(always)] fn clone(&self) -> Self { *self @@ -219,8 +210,7 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_clone", issue = "91805")] - impl<T: ?Sized> const Clone for *mut T { + impl<T: ?Sized> Clone for *mut T { #[inline(always)] fn clone(&self) -> Self { *self @@ -229,8 +219,7 @@ mod impls { /// Shared references can be cloned, but mutable references *cannot*! #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_clone", issue = "91805")] - impl<T: ?Sized> const Clone for &T { + impl<T: ?Sized> Clone for &T { #[inline(always)] #[rustc_diagnostic_item = "noop_method_clone"] fn clone(&self) -> Self { diff --git a/library/core/src/cmp.rs b/library/core/src/cmp.rs index 55331475a..faf48ae57 100644 --- a/library/core/src/cmp.rs +++ b/library/core/src/cmp.rs @@ -25,8 +25,6 @@ mod bytewise; pub(crate) use bytewise::BytewiseEq; -use crate::marker::Destruct; - use self::Ordering::*; /// Trait for equality comparisons. @@ -212,7 +210,6 @@ use self::Ordering::*; label = "no implementation for `{Self} == {Rhs}`", append_const_msg )] -#[const_trait] #[rustc_diagnostic_item = "PartialEq"] pub trait PartialEq<Rhs: ?Sized = Self> { /// This method tests for `self` and `other` values to be equal, and is used @@ -324,17 +321,13 @@ pub struct AssertParamIsEq<T: Eq + ?Sized> { /// ``` /// use std::cmp::Ordering; /// -/// let result = 1.cmp(&2); -/// assert_eq!(Ordering::Less, result); +/// assert_eq!(1.cmp(&2), Ordering::Less); /// -/// let result = 1.cmp(&1); -/// assert_eq!(Ordering::Equal, result); +/// assert_eq!(1.cmp(&1), Ordering::Equal); /// -/// let result = 2.cmp(&1); -/// assert_eq!(Ordering::Greater, result); +/// assert_eq!(2.cmp(&1), Ordering::Greater); /// ``` -#[derive(Clone, Copy, Eq, Debug, Hash)] -#[derive_const(PartialOrd, Ord, PartialEq)] +#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Debug, Hash)] #[stable(feature = "rust1", since = "1.0.0")] #[repr(i8)] pub enum Ordering { @@ -604,8 +597,7 @@ impl Ordering { pub struct Reverse<T>(#[stable(feature = "reverse_cmp_key", since = "1.19.0")] pub T); #[stable(feature = "reverse_cmp_key", since = "1.19.0")] -#[rustc_const_unstable(feature = "const_cmp", issue = "92391")] -impl<T: ~const PartialOrd> const PartialOrd for Reverse<T> { +impl<T: PartialOrd> PartialOrd for Reverse<T> { #[inline] fn partial_cmp(&self, other: &Reverse<T>) -> Option<Ordering> { other.0.partial_cmp(&self.0) @@ -763,7 +755,6 @@ impl<T: Clone> Clone for Reverse<T> { #[doc(alias = ">=")] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_diagnostic_item = "Ord"] -#[const_trait] pub trait Ord: Eq + PartialOrd<Self> { /// This method returns an [`Ordering`] between `self` and `other`. /// @@ -790,8 +781,8 @@ pub trait Ord: Eq + PartialOrd<Self> { /// # Examples /// /// ``` - /// assert_eq!(2, 1.max(2)); - /// assert_eq!(2, 2.max(2)); + /// assert_eq!(1.max(2), 2); + /// assert_eq!(2.max(2), 2); /// ``` #[stable(feature = "ord_max_min", since = "1.21.0")] #[inline] @@ -799,7 +790,6 @@ pub trait Ord: Eq + PartialOrd<Self> { fn max(self, other: Self) -> Self where Self: Sized, - Self: ~const Destruct, { max_by(self, other, Ord::cmp) } @@ -811,8 +801,8 @@ pub trait Ord: Eq + PartialOrd<Self> { /// # Examples /// /// ``` - /// assert_eq!(1, 1.min(2)); - /// assert_eq!(2, 2.min(2)); + /// assert_eq!(1.min(2), 1); + /// assert_eq!(2.min(2), 2); /// ``` #[stable(feature = "ord_max_min", since = "1.21.0")] #[inline] @@ -820,7 +810,6 @@ pub trait Ord: Eq + PartialOrd<Self> { fn min(self, other: Self) -> Self where Self: Sized, - Self: ~const Destruct, { min_by(self, other, Ord::cmp) } @@ -837,17 +826,16 @@ pub trait Ord: Eq + PartialOrd<Self> { /// # Examples /// /// ``` - /// assert!((-3).clamp(-2, 1) == -2); - /// assert!(0.clamp(-2, 1) == 0); - /// assert!(2.clamp(-2, 1) == 1); + /// assert_eq!((-3).clamp(-2, 1), -2); + /// assert_eq!(0.clamp(-2, 1), 0); + /// assert_eq!(2.clamp(-2, 1), 1); /// ``` #[must_use] #[stable(feature = "clamp", since = "1.50.0")] fn clamp(self, min: Self, max: Self) -> Self where Self: Sized, - Self: ~const Destruct, - Self: ~const PartialOrd, + Self: PartialOrd, { assert!(min <= max); if self < min { @@ -1035,7 +1023,6 @@ pub macro Ord($item:item) { label = "no implementation for `{Self} < {Rhs}` and `{Self} > {Rhs}`", append_const_msg )] -#[const_trait] #[rustc_diagnostic_item = "PartialOrd"] pub trait PartialOrd<Rhs: ?Sized = Self>: PartialEq<Rhs> { /// This method returns an ordering between `self` and `other` values if one exists. @@ -1070,11 +1057,9 @@ pub trait PartialOrd<Rhs: ?Sized = Self>: PartialEq<Rhs> { /// # Examples /// /// ``` - /// let result = 1.0 < 2.0; - /// assert_eq!(result, true); - /// - /// let result = 2.0 < 1.0; - /// assert_eq!(result, false); + /// assert_eq!(1.0 < 1.0, false); + /// assert_eq!(1.0 < 2.0, true); + /// assert_eq!(2.0 < 1.0, false); /// ``` #[inline] #[must_use] @@ -1089,11 +1074,9 @@ pub trait PartialOrd<Rhs: ?Sized = Self>: PartialEq<Rhs> { /// # Examples /// /// ``` - /// let result = 1.0 <= 2.0; - /// assert_eq!(result, true); - /// - /// let result = 2.0 <= 2.0; - /// assert_eq!(result, true); + /// assert_eq!(1.0 <= 1.0, true); + /// assert_eq!(1.0 <= 2.0, true); + /// assert_eq!(2.0 <= 1.0, false); /// ``` #[inline] #[must_use] @@ -1107,11 +1090,9 @@ pub trait PartialOrd<Rhs: ?Sized = Self>: PartialEq<Rhs> { /// # Examples /// /// ``` - /// let result = 1.0 > 2.0; - /// assert_eq!(result, false); - /// - /// let result = 2.0 > 2.0; - /// assert_eq!(result, false); + /// assert_eq!(1.0 > 1.0, false); + /// assert_eq!(1.0 > 2.0, false); + /// assert_eq!(2.0 > 1.0, true); /// ``` #[inline] #[must_use] @@ -1126,11 +1107,9 @@ pub trait PartialOrd<Rhs: ?Sized = Self>: PartialEq<Rhs> { /// # Examples /// /// ``` - /// let result = 2.0 >= 1.0; - /// assert_eq!(result, true); - /// - /// let result = 2.0 >= 2.0; - /// assert_eq!(result, true); + /// assert_eq!(1.0 >= 1.0, true); + /// assert_eq!(1.0 >= 2.0, false); + /// assert_eq!(2.0 >= 1.0, true); /// ``` #[inline] #[must_use] @@ -1160,15 +1139,14 @@ pub macro PartialOrd($item:item) { /// ``` /// use std::cmp; /// -/// assert_eq!(1, cmp::min(1, 2)); -/// assert_eq!(2, cmp::min(2, 2)); +/// assert_eq!(cmp::min(1, 2), 1); +/// assert_eq!(cmp::min(2, 2), 2); /// ``` #[inline] #[must_use] #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_cmp", issue = "92391")] #[cfg_attr(not(test), rustc_diagnostic_item = "cmp_min")] -pub const fn min<T: ~const Ord + ~const Destruct>(v1: T, v2: T) -> T { +pub fn min<T: Ord>(v1: T, v2: T) -> T { v1.min(v2) } @@ -1181,18 +1159,16 @@ pub const fn min<T: ~const Ord + ~const Destruct>(v1: T, v2: T) -> T { /// ``` /// use std::cmp; /// -/// assert_eq!(cmp::min_by(-2, 1, |x: &i32, y: &i32| x.abs().cmp(&y.abs())), 1); -/// assert_eq!(cmp::min_by(-2, 2, |x: &i32, y: &i32| x.abs().cmp(&y.abs())), -2); +/// let result = cmp::min_by(-2, 1, |x: &i32, y: &i32| x.abs().cmp(&y.abs())); +/// assert_eq!(result, 1); +/// +/// let result = cmp::min_by(-2, 3, |x: &i32, y: &i32| x.abs().cmp(&y.abs())); +/// assert_eq!(result, -2); /// ``` #[inline] #[must_use] #[stable(feature = "cmp_min_max_by", since = "1.53.0")] -#[rustc_const_unstable(feature = "const_cmp", issue = "92391")] -pub const fn min_by<T, F: ~const FnOnce(&T, &T) -> Ordering>(v1: T, v2: T, compare: F) -> T -where - T: ~const Destruct, - F: ~const Destruct, -{ +pub fn min_by<T, F: FnOnce(&T, &T) -> Ordering>(v1: T, v2: T, compare: F) -> T { match compare(&v1, &v2) { Ordering::Less | Ordering::Equal => v1, Ordering::Greater => v2, @@ -1208,20 +1184,17 @@ where /// ``` /// use std::cmp; /// -/// assert_eq!(cmp::min_by_key(-2, 1, |x: &i32| x.abs()), 1); -/// assert_eq!(cmp::min_by_key(-2, 2, |x: &i32| x.abs()), -2); +/// let result = cmp::min_by_key(-2, 1, |x: &i32| x.abs()); +/// assert_eq!(result, 1); +/// +/// let result = cmp::min_by_key(-2, 2, |x: &i32| x.abs()); +/// assert_eq!(result, -2); /// ``` #[inline] #[must_use] #[stable(feature = "cmp_min_max_by", since = "1.53.0")] -#[rustc_const_unstable(feature = "const_cmp", issue = "92391")] -pub const fn min_by_key<T, F: ~const FnMut(&T) -> K, K: ~const Ord>(v1: T, v2: T, mut f: F) -> T -where - T: ~const Destruct, - F: ~const Destruct, - K: ~const Destruct, -{ - min_by(v1, v2, const |v1, v2| f(v1).cmp(&f(v2))) +pub fn min_by_key<T, F: FnMut(&T) -> K, K: Ord>(v1: T, v2: T, mut f: F) -> T { + min_by(v1, v2, |v1, v2| f(v1).cmp(&f(v2))) } /// Compares and returns the maximum of two values. @@ -1235,15 +1208,14 @@ where /// ``` /// use std::cmp; /// -/// assert_eq!(2, cmp::max(1, 2)); -/// assert_eq!(2, cmp::max(2, 2)); +/// assert_eq!(cmp::max(1, 2), 2); +/// assert_eq!(cmp::max(2, 2), 2); /// ``` #[inline] #[must_use] #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_cmp", issue = "92391")] #[cfg_attr(not(test), rustc_diagnostic_item = "cmp_max")] -pub const fn max<T: ~const Ord + ~const Destruct>(v1: T, v2: T) -> T { +pub fn max<T: Ord>(v1: T, v2: T) -> T { v1.max(v2) } @@ -1256,18 +1228,16 @@ pub const fn max<T: ~const Ord + ~const Destruct>(v1: T, v2: T) -> T { /// ``` /// use std::cmp; /// -/// assert_eq!(cmp::max_by(-2, 1, |x: &i32, y: &i32| x.abs().cmp(&y.abs())), -2); -/// assert_eq!(cmp::max_by(-2, 2, |x: &i32, y: &i32| x.abs().cmp(&y.abs())), 2); +/// let result = cmp::max_by(-2, 1, |x: &i32, y: &i32| x.abs().cmp(&y.abs())); +/// assert_eq!(result, -2); +/// +/// let result = cmp::max_by(-2, 2, |x: &i32, y: &i32| x.abs().cmp(&y.abs())) ; +/// assert_eq!(result, 2); /// ``` #[inline] #[must_use] #[stable(feature = "cmp_min_max_by", since = "1.53.0")] -#[rustc_const_unstable(feature = "const_cmp", issue = "92391")] -pub const fn max_by<T, F: ~const FnOnce(&T, &T) -> Ordering>(v1: T, v2: T, compare: F) -> T -where - T: ~const Destruct, - F: ~const Destruct, -{ +pub fn max_by<T, F: FnOnce(&T, &T) -> Ordering>(v1: T, v2: T, compare: F) -> T { match compare(&v1, &v2) { Ordering::Less | Ordering::Equal => v2, Ordering::Greater => v1, @@ -1283,20 +1253,17 @@ where /// ``` /// use std::cmp; /// -/// assert_eq!(cmp::max_by_key(-2, 1, |x: &i32| x.abs()), -2); -/// assert_eq!(cmp::max_by_key(-2, 2, |x: &i32| x.abs()), 2); +/// let result = cmp::max_by_key(-2, 1, |x: &i32| x.abs()); +/// assert_eq!(result, -2); +/// +/// let result = cmp::max_by_key(-2, 2, |x: &i32| x.abs()); +/// assert_eq!(result, 2); /// ``` #[inline] #[must_use] #[stable(feature = "cmp_min_max_by", since = "1.53.0")] -#[rustc_const_unstable(feature = "const_cmp", issue = "92391")] -pub const fn max_by_key<T, F: ~const FnMut(&T) -> K, K: ~const Ord>(v1: T, v2: T, mut f: F) -> T -where - T: ~const Destruct, - F: ~const Destruct, - K: ~const Destruct, -{ - max_by(v1, v2, const |v1, v2| f(v1).cmp(&f(v2))) +pub fn max_by_key<T, F: FnMut(&T) -> K, K: Ord>(v1: T, v2: T, mut f: F) -> T { + max_by(v1, v2, |v1, v2| f(v1).cmp(&f(v2))) } // Implementation of PartialEq, Eq, PartialOrd and Ord for primitive types @@ -1307,8 +1274,7 @@ mod impls { macro_rules! partial_eq_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl const PartialEq for $t { + impl PartialEq for $t { #[inline] fn eq(&self, other: &$t) -> bool { (*self) == (*other) } #[inline] @@ -1318,8 +1284,7 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl const PartialEq for () { + impl PartialEq for () { #[inline] fn eq(&self, _other: &()) -> bool { true @@ -1346,8 +1311,7 @@ mod impls { macro_rules! partial_ord_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl const PartialOrd for $t { + impl PartialOrd for $t { #[inline] fn partial_cmp(&self, other: &$t) -> Option<Ordering> { match (*self <= *other, *self >= *other) { @@ -1357,21 +1321,20 @@ mod impls { (true, true) => Some(Equal), } } - #[inline] + #[inline(always)] fn lt(&self, other: &$t) -> bool { (*self) < (*other) } - #[inline] + #[inline(always)] fn le(&self, other: &$t) -> bool { (*self) <= (*other) } - #[inline] + #[inline(always)] fn ge(&self, other: &$t) -> bool { (*self) >= (*other) } - #[inline] + #[inline(always)] fn gt(&self, other: &$t) -> bool { (*self) > (*other) } } )*) } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl const PartialOrd for () { + impl PartialOrd for () { #[inline] fn partial_cmp(&self, _: &()) -> Option<Ordering> { Some(Equal) @@ -1379,8 +1342,7 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl const PartialOrd for bool { + impl PartialOrd for bool { #[inline] fn partial_cmp(&self, other: &bool) -> Option<Ordering> { Some(self.cmp(other)) @@ -1392,25 +1354,23 @@ mod impls { macro_rules! ord_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl const PartialOrd for $t { + impl PartialOrd for $t { #[inline] fn partial_cmp(&self, other: &$t) -> Option<Ordering> { Some(self.cmp(other)) } - #[inline] + #[inline(always)] fn lt(&self, other: &$t) -> bool { (*self) < (*other) } - #[inline] + #[inline(always)] fn le(&self, other: &$t) -> bool { (*self) <= (*other) } - #[inline] + #[inline(always)] fn ge(&self, other: &$t) -> bool { (*self) >= (*other) } - #[inline] + #[inline(always)] fn gt(&self, other: &$t) -> bool { (*self) > (*other) } } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl const Ord for $t { + impl Ord for $t { #[inline] fn cmp(&self, other: &$t) -> Ordering { // The order here is important to generate more optimal assembly. @@ -1424,8 +1384,7 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl const Ord for () { + impl Ord for () { #[inline] fn cmp(&self, _other: &()) -> Ordering { Equal @@ -1433,8 +1392,7 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl const Ord for bool { + impl Ord for bool { #[inline] fn cmp(&self, other: &bool) -> Ordering { // Casting to i8's and converting the difference to an Ordering generates @@ -1453,8 +1411,8 @@ mod impls { ord_impl! { char usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 } #[unstable(feature = "never_type", issue = "35121")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl const PartialEq for ! { + impl PartialEq for ! { + #[inline] fn eq(&self, _: &!) -> bool { *self } @@ -1464,16 +1422,16 @@ mod impls { impl Eq for ! {} #[unstable(feature = "never_type", issue = "35121")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl const PartialOrd for ! { + impl PartialOrd for ! { + #[inline] fn partial_cmp(&self, _: &!) -> Option<Ordering> { *self } } #[unstable(feature = "never_type", issue = "35121")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl const Ord for ! { + impl Ord for ! { + #[inline] fn cmp(&self, _: &!) -> Ordering { *self } @@ -1482,10 +1440,9 @@ mod impls { // & pointers #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl<A: ?Sized, B: ?Sized> const PartialEq<&B> for &A + impl<A: ?Sized, B: ?Sized> PartialEq<&B> for &A where - A: ~const PartialEq<B>, + A: PartialEq<B>, { #[inline] fn eq(&self, other: &&B) -> bool { @@ -1497,10 +1454,9 @@ mod impls { } } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl<A: ?Sized, B: ?Sized> const PartialOrd<&B> for &A + impl<A: ?Sized, B: ?Sized> PartialOrd<&B> for &A where - A: ~const PartialOrd<B>, + A: PartialOrd<B>, { #[inline] fn partial_cmp(&self, other: &&B) -> Option<Ordering> { diff --git a/library/core/src/convert/mod.rs b/library/core/src/convert/mod.rs index 5888e2960..38a6d1ccd 100644 --- a/library/core/src/convert/mod.rs +++ b/library/core/src/convert/mod.rs @@ -214,7 +214,6 @@ pub const fn identity<T>(x: T) -> T { /// ``` #[stable(feature = "rust1", since = "1.0.0")] #[cfg_attr(not(test), rustc_diagnostic_item = "AsRef")] -#[const_trait] pub trait AsRef<T: ?Sized> { /// Converts this type into a shared reference of the (usually inferred) input type. #[stable(feature = "rust1", since = "1.0.0")] @@ -366,7 +365,6 @@ pub trait AsRef<T: ?Sized> { /// `&mut Vec<u8>`, for example, is the better choice (callers need to pass the correct type then). #[stable(feature = "rust1", since = "1.0.0")] #[cfg_attr(not(test), rustc_diagnostic_item = "AsMut")] -#[const_trait] pub trait AsMut<T: ?Sized> { /// Converts this type into a mutable reference of the (usually inferred) input type. #[stable(feature = "rust1", since = "1.0.0")] @@ -443,7 +441,6 @@ pub trait AsMut<T: ?Sized> { /// [`Vec`]: ../../std/vec/struct.Vec.html #[rustc_diagnostic_item = "Into"] #[stable(feature = "rust1", since = "1.0.0")] -#[const_trait] pub trait Into<T>: Sized { /// Converts this type into the (usually inferred) input type. #[must_use] @@ -539,7 +536,6 @@ pub trait Into<T>: Sized { all(_Self = "&str", T = "std::string::String"), note = "to coerce a `{T}` into a `{Self}`, use `&*` as a prefix", ))] -#[const_trait] pub trait From<T>: Sized { /// Converts to this type from the input type. #[rustc_diagnostic_item = "from_fn"] @@ -564,7 +560,6 @@ pub trait From<T>: Sized { /// [`Into`], see there for details. #[rustc_diagnostic_item = "TryInto"] #[stable(feature = "try_from", since = "1.34.0")] -#[const_trait] pub trait TryInto<T>: Sized { /// The type returned in the event of a conversion error. #[stable(feature = "try_from", since = "1.34.0")] @@ -641,7 +636,6 @@ pub trait TryInto<T>: Sized { /// [`try_from`]: TryFrom::try_from #[rustc_diagnostic_item = "TryFrom"] #[stable(feature = "try_from", since = "1.34.0")] -#[const_trait] pub trait TryFrom<T>: Sized { /// The type returned in the event of a conversion error. #[stable(feature = "try_from", since = "1.34.0")] @@ -658,10 +652,9 @@ pub trait TryFrom<T>: Sized { // As lifts over & #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T: ?Sized, U: ?Sized> const AsRef<U> for &T +impl<T: ?Sized, U: ?Sized> AsRef<U> for &T where - T: ~const AsRef<U>, + T: AsRef<U>, { #[inline] fn as_ref(&self) -> &U { @@ -671,10 +664,9 @@ where // As lifts over &mut #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T: ?Sized, U: ?Sized> const AsRef<U> for &mut T +impl<T: ?Sized, U: ?Sized> AsRef<U> for &mut T where - T: ~const AsRef<U>, + T: AsRef<U>, { #[inline] fn as_ref(&self) -> &U { @@ -692,10 +684,9 @@ where // AsMut lifts over &mut #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T: ?Sized, U: ?Sized> const AsMut<U> for &mut T +impl<T: ?Sized, U: ?Sized> AsMut<U> for &mut T where - T: ~const AsMut<U>, + T: AsMut<U>, { #[inline] fn as_mut(&mut self) -> &mut U { @@ -713,10 +704,9 @@ where // From implies Into #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T, U> const Into<U> for T +impl<T, U> Into<U> for T where - U: ~const From<T>, + U: From<T>, { /// Calls `U::from(self)`. /// @@ -730,8 +720,7 @@ where // From (and thus Into) is reflexive #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T> const From<T> for T { +impl<T> From<T> for T { /// Returns the argument unchanged. #[inline(always)] fn from(t: T) -> T { @@ -748,8 +737,7 @@ impl<T> const From<T> for T { #[allow(unused_attributes)] // FIXME(#58633): do a principled fix instead. #[rustc_reservation_impl = "permitting this impl would forbid us from adding \ `impl<T> From<!> for T` later; see rust-lang/rust#64715 for details"] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T> const From<!> for T { +impl<T> From<!> for T { fn from(t: !) -> T { t } @@ -757,10 +745,9 @@ impl<T> const From<!> for T { // TryFrom implies TryInto #[stable(feature = "try_from", since = "1.34.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T, U> const TryInto<U> for T +impl<T, U> TryInto<U> for T where - U: ~const TryFrom<T>, + U: TryFrom<T>, { type Error = U::Error; @@ -773,10 +760,9 @@ where // Infallible conversions are semantically equivalent to fallible conversions // with an uninhabited error type. #[stable(feature = "try_from", since = "1.34.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T, U> const TryFrom<U> for T +impl<T, U> TryFrom<U> for T where - U: ~const Into<T>, + U: Into<T>, { type Error = Infallible; @@ -876,8 +862,7 @@ impl AsMut<str> for str { pub enum Infallible {} #[stable(feature = "convert_infallible", since = "1.34.0")] -#[rustc_const_unstable(feature = "const_clone", issue = "91805")] -impl const Clone for Infallible { +impl Clone for Infallible { fn clone(&self) -> Infallible { match *self {} } @@ -929,8 +914,8 @@ impl Ord for Infallible { } #[stable(feature = "convert_infallible", since = "1.34.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl const From<!> for Infallible { +impl From<!> for Infallible { + #[inline] fn from(x: !) -> Self { x } diff --git a/library/core/src/convert/num.rs b/library/core/src/convert/num.rs index a74a56bc5..56ab63be2 100644 --- a/library/core/src/convert/num.rs +++ b/library/core/src/convert/num.rs @@ -44,8 +44,7 @@ impl_float_to_int!(f64 => u8 u16 u32 u64 u128 usize i8 i16 i32 i64 i128 isize); macro_rules! impl_from { ($Small: ty, $Large: ty, #[$attr:meta], $doc: expr) => { #[$attr] - #[rustc_const_unstable(feature = "const_num_from_num", issue = "87852")] - impl const From<$Small> for $Large { + impl From<$Small> for $Large { // Rustdocs on the impl block show a "[+] show undocumented items" toggle. // Rustdocs on functions do not. #[doc = $doc] @@ -170,8 +169,7 @@ impl_from! { f32, f64, #[stable(feature = "lossless_float_conv", since = "1.6.0" // bool -> Float #[stable(feature = "float_from_bool", since = "1.68.0")] -#[rustc_const_unstable(feature = "const_num_from_num", issue = "87852")] -impl const From<bool> for f32 { +impl From<bool> for f32 { /// Converts `bool` to `f32` losslessly. The resulting value is positive /// `0.0` for `false` and `1.0` for `true` values. /// @@ -190,8 +188,7 @@ impl const From<bool> for f32 { } } #[stable(feature = "float_from_bool", since = "1.68.0")] -#[rustc_const_unstable(feature = "const_num_from_num", issue = "87852")] -impl const From<bool> for f64 { +impl From<bool> for f64 { /// Converts `bool` to `f64` losslessly. The resulting value is positive /// `0.0` for `false` and `1.0` for `true` values. /// @@ -214,8 +211,7 @@ impl const From<bool> for f64 { macro_rules! try_from_unbounded { ($source:ty, $($target:ty),*) => {$( #[stable(feature = "try_from", since = "1.34.0")] - #[rustc_const_unstable(feature = "const_num_from_num", issue = "87852")] - impl const TryFrom<$source> for $target { + impl TryFrom<$source> for $target { type Error = TryFromIntError; /// Try to create the target number type from a source @@ -233,8 +229,7 @@ macro_rules! try_from_unbounded { macro_rules! try_from_lower_bounded { ($source:ty, $($target:ty),*) => {$( #[stable(feature = "try_from", since = "1.34.0")] - #[rustc_const_unstable(feature = "const_num_from_num", issue = "87852")] - impl const TryFrom<$source> for $target { + impl TryFrom<$source> for $target { type Error = TryFromIntError; /// Try to create the target number type from a source @@ -256,8 +251,7 @@ macro_rules! try_from_lower_bounded { macro_rules! try_from_upper_bounded { ($source:ty, $($target:ty),*) => {$( #[stable(feature = "try_from", since = "1.34.0")] - #[rustc_const_unstable(feature = "const_num_from_num", issue = "87852")] - impl const TryFrom<$source> for $target { + impl TryFrom<$source> for $target { type Error = TryFromIntError; /// Try to create the target number type from a source @@ -279,8 +273,7 @@ macro_rules! try_from_upper_bounded { macro_rules! try_from_both_bounded { ($source:ty, $($target:ty),*) => {$( #[stable(feature = "try_from", since = "1.34.0")] - #[rustc_const_unstable(feature = "const_num_from_num", issue = "87852")] - impl const TryFrom<$source> for $target { + impl TryFrom<$source> for $target { type Error = TryFromIntError; /// Try to create the target number type from a source @@ -431,8 +424,7 @@ use crate::num::NonZeroUsize; macro_rules! nzint_impl_from { ($Small: ty, $Large: ty, #[$attr:meta], $doc: expr) => { #[$attr] - #[rustc_const_unstable(feature = "const_num_from_num", issue = "87852")] - impl const From<$Small> for $Large { + impl From<$Small> for $Large { // Rustdocs on the impl block show a "[+] show undocumented items" toggle. // Rustdocs on functions do not. #[doc = $doc] diff --git a/library/core/src/default.rs b/library/core/src/default.rs index d96b53de0..09dbc9581 100644 --- a/library/core/src/default.rs +++ b/library/core/src/default.rs @@ -99,7 +99,6 @@ /// ``` #[cfg_attr(not(test), rustc_diagnostic_item = "Default")] #[stable(feature = "rust1", since = "1.0.0")] -#[const_trait] pub trait Default: Sized { /// Returns the "default value" for a type. /// @@ -190,8 +189,7 @@ pub macro Default($item:item) { macro_rules! default_impl { ($t:ty, $v:expr, $doc:tt) => { #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] - impl const Default for $t { + impl Default for $t { #[inline] #[doc = $doc] fn default() -> $t { diff --git a/library/core/src/escape.rs b/library/core/src/escape.rs new file mode 100644 index 000000000..3d471419b --- /dev/null +++ b/library/core/src/escape.rs @@ -0,0 +1,112 @@ +//! Helper code for character escaping. + +use crate::ascii; +use crate::num::NonZeroUsize; +use crate::ops::Range; + +const HEX_DIGITS: [ascii::Char; 16] = *b"0123456789abcdef".as_ascii().unwrap(); + +/// Escapes a byte into provided buffer; returns length of escaped +/// representation. +pub(crate) fn escape_ascii_into(output: &mut [ascii::Char; 4], byte: u8) -> Range<u8> { + #[inline] + fn backslash(a: ascii::Char) -> ([ascii::Char; 4], u8) { + ([ascii::Char::ReverseSolidus, a, ascii::Char::Null, ascii::Char::Null], 2) + } + + let (data, len) = match byte { + b'\t' => backslash(ascii::Char::SmallT), + b'\r' => backslash(ascii::Char::SmallR), + b'\n' => backslash(ascii::Char::SmallN), + b'\\' => backslash(ascii::Char::ReverseSolidus), + b'\'' => backslash(ascii::Char::Apostrophe), + b'\"' => backslash(ascii::Char::QuotationMark), + _ => if let Some(a) = byte.as_ascii() && !byte.is_ascii_control() { + ([a, ascii::Char::Null, ascii::Char::Null, ascii::Char::Null], 1) + } else { + let hi = HEX_DIGITS[usize::from(byte >> 4)]; + let lo = HEX_DIGITS[usize::from(byte & 0xf)]; + ([ascii::Char::ReverseSolidus, ascii::Char::SmallX, hi, lo], 4) + } + }; + *output = data; + 0..len +} + +/// Escapes a character into provided buffer using `\u{NNNN}` representation. +pub(crate) fn escape_unicode_into(output: &mut [ascii::Char; 10], ch: char) -> Range<u8> { + output[9] = ascii::Char::RightCurlyBracket; + + let ch = ch as u32; + output[3] = HEX_DIGITS[((ch >> 20) & 15) as usize]; + output[4] = HEX_DIGITS[((ch >> 16) & 15) as usize]; + output[5] = HEX_DIGITS[((ch >> 12) & 15) as usize]; + output[6] = HEX_DIGITS[((ch >> 8) & 15) as usize]; + output[7] = HEX_DIGITS[((ch >> 4) & 15) as usize]; + output[8] = HEX_DIGITS[((ch >> 0) & 15) as usize]; + + // or-ing 1 ensures that for ch==0 the code computes that one digit should + // be printed. + let start = (ch | 1).leading_zeros() as usize / 4 - 2; + const UNICODE_ESCAPE_PREFIX: &[ascii::Char; 3] = b"\\u{".as_ascii().unwrap(); + output[start..][..3].copy_from_slice(UNICODE_ESCAPE_PREFIX); + + (start as u8)..10 +} + +/// An iterator over an fixed-size array. +/// +/// This is essentially equivalent to array’s IntoIter except that indexes are +/// limited to u8 to reduce size of the structure. +#[derive(Clone, Debug)] +pub(crate) struct EscapeIterInner<const N: usize> { + // The element type ensures this is always ASCII, and thus also valid UTF-8. + pub(crate) data: [ascii::Char; N], + + // Invariant: alive.start <= alive.end <= N. + pub(crate) alive: Range<u8>, +} + +impl<const N: usize> EscapeIterInner<N> { + pub fn new(data: [ascii::Char; N], alive: Range<u8>) -> Self { + const { assert!(N < 256) }; + debug_assert!(alive.start <= alive.end && usize::from(alive.end) <= N, "{alive:?}"); + Self { data, alive } + } + + pub fn from_array<const M: usize>(array: [ascii::Char; M]) -> Self { + const { assert!(M <= N) }; + + let mut data = [ascii::Char::Null; N]; + data[..M].copy_from_slice(&array); + Self::new(data, 0..M as u8) + } + + pub fn as_ascii(&self) -> &[ascii::Char] { + &self.data[usize::from(self.alive.start)..usize::from(self.alive.end)] + } + + pub fn as_str(&self) -> &str { + self.as_ascii().as_str() + } + + pub fn len(&self) -> usize { + usize::from(self.alive.end - self.alive.start) + } + + pub fn next(&mut self) -> Option<u8> { + self.alive.next().map(|i| self.data[usize::from(i)].as_u8()) + } + + pub fn next_back(&mut self) -> Option<u8> { + self.alive.next_back().map(|i| self.data[usize::from(i)].as_u8()) + } + + pub fn advance_by(&mut self, n: usize) -> Result<(), NonZeroUsize> { + self.alive.advance_by(n) + } + + pub fn advance_back_by(&mut self, n: usize) -> Result<(), NonZeroUsize> { + self.alive.advance_back_by(n) + } +} diff --git a/library/core/src/ffi/c_str.rs b/library/core/src/ffi/c_str.rs index 4a5306cca..e1e1a9b40 100644 --- a/library/core/src/ffi/c_str.rs +++ b/library/core/src/ffi/c_str.rs @@ -79,9 +79,9 @@ use crate::str; /// /// [str]: prim@str "str" #[derive(Hash)] -#[cfg_attr(not(test), rustc_diagnostic_item = "CStr")] #[stable(feature = "core_c_str", since = "1.64.0")] #[rustc_has_incoherent_inherent_impls] +#[cfg_attr(not(bootstrap), lang = "CStr")] // FIXME: // `fn from` in `impl From<&CStr> for Box<CStr>` current implementation relies // on `CStr` being layout-compatible with `[u8]`. @@ -324,14 +324,15 @@ impl CStr { /// assert_eq!(c_str.to_str().unwrap(), "AAAAAAAA"); /// ``` /// - #[rustc_allow_const_fn_unstable(const_slice_index)] #[stable(feature = "cstr_from_bytes_until_nul", since = "1.69.0")] #[rustc_const_stable(feature = "cstr_from_bytes_until_nul", since = "1.69.0")] pub const fn from_bytes_until_nul(bytes: &[u8]) -> Result<&CStr, FromBytesUntilNulError> { let nul_pos = memchr::memchr(0, bytes); match nul_pos { Some(nul_pos) => { - let subslice = &bytes[..nul_pos + 1]; + // FIXME(const-hack) replace with range index + // SAFETY: nul_pos + 1 <= bytes.len() + let subslice = unsafe { crate::slice::from_raw_parts(bytes.as_ptr(), nul_pos + 1) }; // SAFETY: We know there is a nul byte at nul_pos, so this slice // (ending at the nul byte) is a well-formed C string. Ok(unsafe { CStr::from_bytes_with_nul_unchecked(subslice) }) @@ -516,8 +517,6 @@ impl CStr { /// # Examples /// /// ``` - /// #![feature(cstr_is_empty)] - /// /// use std::ffi::CStr; /// # use std::ffi::FromBytesWithNulError; /// @@ -532,11 +531,13 @@ impl CStr { /// # } /// ``` #[inline] - #[unstable(feature = "cstr_is_empty", issue = "102444")] + #[stable(feature = "cstr_is_empty", since = "1.71.0")] + #[rustc_const_stable(feature = "cstr_is_empty", since = "1.71.0")] pub const fn is_empty(&self) -> bool { // SAFETY: We know there is at least one byte; for empty strings it // is the NUL terminator. - (unsafe { self.inner.get_unchecked(0) }) == &0 + // FIXME(const-hack): use get_unchecked + unsafe { *self.inner.as_ptr() == 0 } } /// Converts this C string to a byte slice. @@ -560,8 +561,7 @@ impl CStr { #[must_use = "this returns the result of the operation, \ without modifying the original"] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cstr_methods", issue = "101719")] - pub const fn to_bytes(&self) -> &[u8] { + pub fn to_bytes(&self) -> &[u8] { let bytes = self.to_bytes_with_nul(); // SAFETY: to_bytes_with_nul returns slice with length at least 1 unsafe { bytes.get_unchecked(..bytes.len() - 1) } @@ -612,8 +612,7 @@ impl CStr { /// assert_eq!(cstr.to_str(), Ok("foo")); /// ``` #[stable(feature = "cstr_to_str", since = "1.4.0")] - #[rustc_const_unstable(feature = "const_cstr_methods", issue = "101719")] - pub const fn to_str(&self) -> Result<&str, str::Utf8Error> { + pub fn to_str(&self) -> Result<&str, str::Utf8Error> { // N.B., when `CStr` is changed to perform the length check in `.to_bytes()` // instead of in `from_ptr()`, it may be worth considering if this should // be rewritten to do the UTF-8 check inline with the length calculation diff --git a/library/core/src/ffi/mod.rs b/library/core/src/ffi/mod.rs index c4f554c8c..b73abbbac 100644 --- a/library/core/src/ffi/mod.rs +++ b/library/core/src/ffi/mod.rs @@ -143,7 +143,10 @@ mod c_char_definition { target_arch = "powerpc" ) ), - all(target_os = "fuchsia", target_arch = "aarch64"), + all( + target_os = "fuchsia", + any(target_arch = "aarch64", target_arch = "riscv64") + ), all(target_os = "nto", target_arch = "aarch64"), target_os = "horizon" ))] { @@ -199,7 +202,8 @@ mod c_long_definition { // would be uninhabited and at least dereferencing such pointers would // be UB. #[doc = include_str!("c_void.md")] -#[repr(u8)] +#[cfg_attr(not(bootstrap), lang = "c_void")] +#[cfg_attr(not(doc), repr(u8))] // work around https://github.com/rust-lang/rust/issues/90435 #[stable(feature = "core_c_void", since = "1.30.0")] pub enum c_void { #[unstable( @@ -240,7 +244,7 @@ impl fmt::Debug for c_void { target_os = "uefi", windows, ))] -#[repr(transparent)] +#[cfg_attr(not(doc), repr(transparent))] // work around https://github.com/rust-lang/rust/issues/90435 #[unstable( feature = "c_variadic", reason = "the `c_variadic` feature has not been properly tested on \ @@ -292,7 +296,7 @@ impl<'f> fmt::Debug for VaListImpl<'f> { not(target_os = "uefi"), not(windows), ))] -#[repr(C)] +#[cfg_attr(not(doc), repr(C))] // work around https://github.com/rust-lang/rust/issues/66401 #[derive(Debug)] #[unstable( feature = "c_variadic", @@ -312,7 +316,7 @@ pub struct VaListImpl<'f> { /// PowerPC ABI implementation of a `va_list`. #[cfg(all(target_arch = "powerpc", not(target_os = "uefi"), not(windows)))] -#[repr(C)] +#[cfg_attr(not(doc), repr(C))] // work around https://github.com/rust-lang/rust/issues/66401 #[derive(Debug)] #[unstable( feature = "c_variadic", @@ -332,7 +336,7 @@ pub struct VaListImpl<'f> { /// s390x ABI implementation of a `va_list`. #[cfg(target_arch = "s390x")] -#[repr(C)] +#[cfg_attr(not(doc), repr(C))] // work around https://github.com/rust-lang/rust/issues/66401 #[derive(Debug)] #[unstable( feature = "c_variadic", @@ -351,7 +355,7 @@ pub struct VaListImpl<'f> { /// x86_64 ABI implementation of a `va_list`. #[cfg(all(target_arch = "x86_64", not(target_os = "uefi"), not(windows)))] -#[repr(C)] +#[cfg_attr(not(doc), repr(C))] // work around https://github.com/rust-lang/rust/issues/66401 #[derive(Debug)] #[unstable( feature = "c_variadic", @@ -369,7 +373,7 @@ pub struct VaListImpl<'f> { } /// A wrapper for a `va_list` -#[repr(transparent)] +#[cfg_attr(not(doc), repr(transparent))] // work around https://github.com/rust-lang/rust/issues/90435 #[derive(Debug)] #[unstable( feature = "c_variadic", diff --git a/library/core/src/fmt/builders.rs b/library/core/src/fmt/builders.rs index 7da49b04a..36f49d51c 100644 --- a/library/core/src/fmt/builders.rs +++ b/library/core/src/fmt/builders.rs @@ -60,7 +60,7 @@ impl fmt::Write for PadAdapter<'_, '_> { /// } /// /// impl fmt::Debug for Foo { -/// fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { +/// fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { /// fmt.debug_struct("Foo") /// .field("bar", &self.bar) /// .field("baz", &self.baz) @@ -109,14 +109,14 @@ impl<'a, 'b: 'a> DebugStruct<'a, 'b> { /// .field("bar", &self.bar) // We add `bar` field. /// .field("another", &self.another) // We add `another` field. /// // We even add a field which doesn't exist (because why not?). - /// .field("not_existing_field", &1) + /// .field("nonexistent_field", &1) /// .finish() // We're good to go! /// } /// } /// /// assert_eq!( /// format!("{:?}", Bar { bar: 10, another: "Hello World".to_string() }), - /// "Bar { bar: 10, another: \"Hello World\", not_existing_field: 1 }", + /// "Bar { bar: 10, another: \"Hello World\", nonexistent_field: 1 }", /// ); /// ``` #[stable(feature = "debug_builders", since = "1.2.0")] @@ -249,7 +249,7 @@ impl<'a, 'b: 'a> DebugStruct<'a, 'b> { /// struct Foo(i32, String); /// /// impl fmt::Debug for Foo { -/// fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { +/// fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { /// fmt.debug_tuple("Foo") /// .field(&self.0) /// .field(&self.1) @@ -418,7 +418,7 @@ impl<'a, 'b: 'a> DebugInner<'a, 'b> { /// struct Foo(Vec<i32>); /// /// impl fmt::Debug for Foo { -/// fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { +/// fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { /// fmt.debug_set().entries(self.0.iter()).finish() /// } /// } @@ -548,7 +548,7 @@ impl<'a, 'b: 'a> DebugSet<'a, 'b> { /// struct Foo(Vec<i32>); /// /// impl fmt::Debug for Foo { -/// fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { +/// fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { /// fmt.debug_list().entries(self.0.iter()).finish() /// } /// } @@ -678,7 +678,7 @@ impl<'a, 'b: 'a> DebugList<'a, 'b> { /// struct Foo(Vec<(String, i32)>); /// /// impl fmt::Debug for Foo { -/// fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { +/// fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { /// fmt.debug_map().entries(self.0.iter().map(|&(ref k, ref v)| (k, v))).finish() /// } /// } diff --git a/library/core/src/fmt/float.rs b/library/core/src/fmt/float.rs index 89d5fac30..3bbf5d877 100644 --- a/library/core/src/fmt/float.rs +++ b/library/core/src/fmt/float.rs @@ -45,7 +45,8 @@ where &mut buf, &mut parts, ); - fmt.pad_formatted_parts(&formatted) + // SAFETY: `to_exact_fixed_str` and `format_exact` produce only ASCII characters. + unsafe { fmt.pad_formatted_parts(&formatted) } } // Don't inline this so callers that call both this and the above won't wind @@ -71,7 +72,8 @@ where &mut buf, &mut parts, ); - fmt.pad_formatted_parts(&formatted) + // SAFETY: `to_shortest_str` and `format_shortest` produce only ASCII characters. + unsafe { fmt.pad_formatted_parts(&formatted) } } fn float_to_decimal_display<T>(fmt: &mut Formatter<'_>, num: &T) -> Result @@ -116,7 +118,8 @@ where &mut buf, &mut parts, ); - fmt.pad_formatted_parts(&formatted) + // SAFETY: `to_exact_exp_str` and `format_exact` produce only ASCII characters. + unsafe { fmt.pad_formatted_parts(&formatted) } } // Don't inline this so callers that call both this and the above won't wind @@ -143,7 +146,8 @@ where &mut buf, &mut parts, ); - fmt.pad_formatted_parts(&formatted) + // SAFETY: `to_shortest_exp_str` and `format_shortest` produce only ASCII characters. + unsafe { fmt.pad_formatted_parts(&formatted) } } // Common code of floating point LowerExp and UpperExp. diff --git a/library/core/src/fmt/mod.rs b/library/core/src/fmt/mod.rs index fcda097f0..1786b309c 100644 --- a/library/core/src/fmt/mod.rs +++ b/library/core/src/fmt/mod.rs @@ -18,6 +18,7 @@ mod float; #[cfg(no_fp_fmt_parse)] mod nofloat; mod num; +mod rt; #[stable(feature = "fmt_flags_align", since = "1.28.0")] #[cfg_attr(not(test), rustc_diagnostic_item = "Alignment")] @@ -38,12 +39,6 @@ pub enum Alignment { #[stable(feature = "debug_builders", since = "1.2.0")] pub use self::builders::{DebugList, DebugMap, DebugSet, DebugStruct, DebugTuple}; -#[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] -#[doc(hidden)] -pub mod rt { - pub mod v1; -} - /// The type returned by formatter methods. /// /// # Examples @@ -227,7 +222,7 @@ impl<W: Write + ?Sized> Write for &mut W { pub struct Formatter<'a> { flags: u32, fill: char, - align: rt::v1::Alignment, + align: rt::Alignment, width: Option<usize>, precision: Option<usize>, @@ -248,7 +243,7 @@ impl<'a> Formatter<'a> { Formatter { flags: 0, fill: ' ', - align: rt::v1::Alignment::Unknown, + align: rt::Alignment::Unknown, width: None, precision: None, buf, @@ -256,145 +251,48 @@ impl<'a> Formatter<'a> { } } -// NB. Argument is essentially an optimized partially applied formatting function, -// equivalent to `exists T.(&T, fn(&T, &mut Formatter<'_>) -> Result`. - -extern "C" { - type Opaque; -} - -/// This struct represents the generic "argument" which is taken by the Xprintf -/// family of functions. It contains a function to format the given value. At -/// compile time it is ensured that the function and the value have the correct -/// types, and then this struct is used to canonicalize arguments to one type. -#[lang = "format_argument"] +/// This structure represents a safely precompiled version of a format string +/// and its arguments. This cannot be generated at runtime because it cannot +/// safely be done, so no constructors are given and the fields are private +/// to prevent modification. +/// +/// The [`format_args!`] macro will safely create an instance of this structure. +/// The macro validates the format string at compile-time so usage of the +/// [`write()`] and [`format()`] functions can be safely performed. +/// +/// You can use the `Arguments<'a>` that [`format_args!`] returns in `Debug` +/// and `Display` contexts as seen below. The example also shows that `Debug` +/// and `Display` format to the same thing: the interpolated format string +/// in `format_args!`. +/// +/// ```rust +/// let debug = format!("{:?}", format_args!("{} foo {:?}", 1, 2)); +/// let display = format!("{}", format_args!("{} foo {:?}", 1, 2)); +/// assert_eq!("1 foo 2", display); +/// assert_eq!(display, debug); +/// ``` +/// +/// [`format()`]: ../../std/fmt/fn.format.html +#[lang = "format_arguments"] +#[stable(feature = "rust1", since = "1.0.0")] #[derive(Copy, Clone)] -#[allow(missing_debug_implementations)] -#[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] -#[doc(hidden)] -pub struct ArgumentV1<'a> { - value: &'a Opaque, - formatter: fn(&Opaque, &mut Formatter<'_>) -> Result, -} - -/// This struct represents the unsafety of constructing an `Arguments`. -/// It exists, rather than an unsafe function, in order to simplify the expansion -/// of `format_args!(..)` and reduce the scope of the `unsafe` block. -#[lang = "format_unsafe_arg"] -#[allow(missing_debug_implementations)] -#[doc(hidden)] -#[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] -pub struct UnsafeArg { - _private: (), -} - -impl UnsafeArg { - /// See documentation where `UnsafeArg` is required to know when it is safe to - /// create and use `UnsafeArg`. - #[doc(hidden)] - #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] - #[inline(always)] - pub unsafe fn new() -> Self { - Self { _private: () } - } -} - -// This guarantees a single stable value for the function pointer associated with -// indices/counts in the formatting infrastructure. -// -// Note that a function defined as such would not be correct as functions are -// always tagged unnamed_addr with the current lowering to LLVM IR, so their -// address is not considered important to LLVM and as such the as_usize cast -// could have been miscompiled. In practice, we never call as_usize on non-usize -// containing data (as a matter of static generation of the formatting -// arguments), so this is merely an additional check. -// -// We primarily want to ensure that the function pointer at `USIZE_MARKER` has -// an address corresponding *only* to functions that also take `&usize` as their -// first argument. The read_volatile here ensures that we can safely ready out a -// usize from the passed reference and that this address does not point at a -// non-usize taking function. -#[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] -static USIZE_MARKER: fn(&usize, &mut Formatter<'_>) -> Result = |ptr, _| { - // SAFETY: ptr is a reference - let _v: usize = unsafe { crate::ptr::read_volatile(ptr) }; - loop {} -}; - -macro_rules! arg_new { - ($f: ident, $t: ident) => { - #[doc(hidden)] - #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] - #[inline] - pub fn $f<'b, T: $t>(x: &'b T) -> ArgumentV1<'_> { - Self::new(x, $t::fmt) - } - }; -} - -#[rustc_diagnostic_item = "ArgumentV1Methods"] -impl<'a> ArgumentV1<'a> { - #[doc(hidden)] - #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] - #[inline] - pub fn new<'b, T>(x: &'b T, f: fn(&T, &mut Formatter<'_>) -> Result) -> ArgumentV1<'b> { - // SAFETY: `mem::transmute(x)` is safe because - // 1. `&'b T` keeps the lifetime it originated with `'b` - // (so as to not have an unbounded lifetime) - // 2. `&'b T` and `&'b Opaque` have the same memory layout - // (when `T` is `Sized`, as it is here) - // `mem::transmute(f)` is safe since `fn(&T, &mut Formatter<'_>) -> Result` - // and `fn(&Opaque, &mut Formatter<'_>) -> Result` have the same ABI - // (as long as `T` is `Sized`) - unsafe { ArgumentV1 { formatter: mem::transmute(f), value: mem::transmute(x) } } - } - - arg_new!(new_display, Display); - arg_new!(new_debug, Debug); - arg_new!(new_octal, Octal); - arg_new!(new_lower_hex, LowerHex); - arg_new!(new_upper_hex, UpperHex); - arg_new!(new_pointer, Pointer); - arg_new!(new_binary, Binary); - arg_new!(new_lower_exp, LowerExp); - arg_new!(new_upper_exp, UpperExp); +pub struct Arguments<'a> { + // Format string pieces to print. + pieces: &'a [&'static str], - #[doc(hidden)] - #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] - pub fn from_usize(x: &usize) -> ArgumentV1<'_> { - ArgumentV1::new(x, USIZE_MARKER) - } - - fn as_usize(&self) -> Option<usize> { - // We are type punning a bit here: USIZE_MARKER only takes an &usize but - // formatter takes an &Opaque. Rust understandably doesn't think we should compare - // the function pointers if they don't have the same signature, so we cast to - // usizes to tell it that we just want to compare addresses. - if self.formatter as usize == USIZE_MARKER as usize { - // SAFETY: The `formatter` field is only set to USIZE_MARKER if - // the value is a usize, so this is safe - Some(unsafe { *(self.value as *const _ as *const usize) }) - } else { - None - } - } -} + // Placeholder specs, or `None` if all specs are default (as in "{}{}"). + fmt: Option<&'a [rt::Placeholder]>, -// flags available in the v1 format of format_args -#[derive(Copy, Clone)] -enum FlagV1 { - SignPlus, - SignMinus, - Alternate, - SignAwareZeroPad, - DebugLowerHex, - DebugUpperHex, + // Dynamic arguments for interpolation, to be interleaved with string + // pieces. (Every argument is preceded by a string piece.) + args: &'a [rt::Argument<'a>], } +/// Used by the format_args!() macro to create a fmt::Arguments object. +#[doc(hidden)] +#[unstable(feature = "fmt_internals", issue = "none")] impl<'a> Arguments<'a> { - #[doc(hidden)] #[inline] - #[unstable(feature = "fmt_internals", issue = "none")] #[rustc_const_unstable(feature = "const_fmt_arguments_new", issue = "none")] pub const fn new_const(pieces: &'a [&'static str]) -> Self { if pieces.len() > 1 { @@ -405,23 +303,8 @@ impl<'a> Arguments<'a> { /// When using the format_args!() macro, this function is used to generate the /// Arguments structure. - #[cfg(not(bootstrap))] - #[doc(hidden)] #[inline] - #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] - pub fn new_v1(pieces: &'a [&'static str], args: &'a [ArgumentV1<'a>]) -> Arguments<'a> { - if pieces.len() < args.len() || pieces.len() > args.len() + 1 { - panic!("invalid args"); - } - Arguments { pieces, fmt: None, args } - } - - #[cfg(bootstrap)] - #[doc(hidden)] - #[inline] - #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] - #[rustc_const_unstable(feature = "const_fmt_arguments_new", issue = "none")] - pub const fn new_v1(pieces: &'a [&'static str], args: &'a [ArgumentV1<'a>]) -> Arguments<'a> { + pub fn new_v1(pieces: &'a [&'static str], args: &'a [rt::Argument<'a>]) -> Arguments<'a> { if pieces.len() < args.len() || pieces.len() > args.len() + 1 { panic!("invalid args"); } @@ -430,21 +313,17 @@ impl<'a> Arguments<'a> { /// This function is used to specify nonstandard formatting parameters. /// - /// An `UnsafeArg` is required because the following invariants must be held + /// An `rt::UnsafeArg` is required because the following invariants must be held /// in order for this function to be safe: /// 1. The `pieces` slice must be at least as long as `fmt`. - /// 2. Every [`rt::v1::Argument::position`] value within `fmt` must be a - /// valid index of `args`. - /// 3. Every [`rt::v1::Count::Param`] within `fmt` must contain a valid index of - /// `args`. - #[doc(hidden)] + /// 2. Every `rt::Placeholder::position` value within `fmt` must be a valid index of `args`. + /// 3. Every `rt::Count::Param` within `fmt` must contain a valid index of `args`. #[inline] - #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] pub fn new_v1_formatted( pieces: &'a [&'static str], - args: &'a [ArgumentV1<'a>], - fmt: &'a [rt::v1::Argument], - _unsafe_arg: UnsafeArg, + args: &'a [rt::Argument<'a>], + fmt: &'a [rt::Placeholder], + _unsafe_arg: rt::UnsafeArg, ) -> Arguments<'a> { Arguments { pieces, fmt: Some(fmt), args } } @@ -453,9 +332,7 @@ impl<'a> Arguments<'a> { /// /// This is intended to be used for setting initial `String` capacity /// when using `format!`. Note: this is neither the lower nor upper bound. - #[doc(hidden)] #[inline] - #[unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] pub fn estimated_capacity(&self) -> usize { let pieces_length: usize = self.pieces.iter().map(|x| x.len()).sum(); @@ -475,43 +352,6 @@ impl<'a> Arguments<'a> { } } -/// This structure represents a safely precompiled version of a format string -/// and its arguments. This cannot be generated at runtime because it cannot -/// safely be done, so no constructors are given and the fields are private -/// to prevent modification. -/// -/// The [`format_args!`] macro will safely create an instance of this structure. -/// The macro validates the format string at compile-time so usage of the -/// [`write()`] and [`format()`] functions can be safely performed. -/// -/// You can use the `Arguments<'a>` that [`format_args!`] returns in `Debug` -/// and `Display` contexts as seen below. The example also shows that `Debug` -/// and `Display` format to the same thing: the interpolated format string -/// in `format_args!`. -/// -/// ```rust -/// let debug = format!("{:?}", format_args!("{} foo {:?}", 1, 2)); -/// let display = format!("{}", format_args!("{} foo {:?}", 1, 2)); -/// assert_eq!("1 foo 2", display); -/// assert_eq!(display, debug); -/// ``` -/// -/// [`format()`]: ../../std/fmt/fn.format.html -#[lang = "format_arguments"] -#[stable(feature = "rust1", since = "1.0.0")] -#[derive(Copy, Clone)] -pub struct Arguments<'a> { - // Format string pieces to print. - pieces: &'a [&'static str], - - // Placeholder specs, or `None` if all specs are default (as in "{}{}"). - fmt: Option<&'a [rt::v1::Argument]>, - - // Dynamic arguments for interpolation, to be interleaved with string - // pieces. (Every argument is preceded by a string piece.) - args: &'a [ArgumentV1<'a>], -} - impl<'a> Arguments<'a> { /// Get the formatted string, if it has no arguments to be formatted at runtime. /// @@ -541,7 +381,7 @@ impl<'a> Arguments<'a> { /// /// fn write_str(_: &str) { /* ... */ } /// - /// fn write_fmt(args: &Arguments) { + /// fn write_fmt(args: &Arguments<'_>) { /// if let Some(s) = args.as_str() { /// write_str(s) /// } else { @@ -1251,7 +1091,7 @@ pub fn write(output: &mut dyn Write, args: Arguments<'_>) -> Result { if !piece.is_empty() { formatter.buf.write_str(*piece)?; } - (arg.formatter)(arg.value, &mut formatter)?; + arg.fmt(&mut formatter)?; idx += 1; } } @@ -1281,15 +1121,15 @@ pub fn write(output: &mut dyn Write, args: Arguments<'_>) -> Result { Ok(()) } -unsafe fn run(fmt: &mut Formatter<'_>, arg: &rt::v1::Argument, args: &[ArgumentV1<'_>]) -> Result { - fmt.fill = arg.format.fill; - fmt.align = arg.format.align; - fmt.flags = arg.format.flags; +unsafe fn run(fmt: &mut Formatter<'_>, arg: &rt::Placeholder, args: &[rt::Argument<'_>]) -> Result { + fmt.fill = arg.fill; + fmt.align = arg.align; + fmt.flags = arg.flags; // SAFETY: arg and args come from the same Arguments, // which guarantees the indexes are always within bounds. unsafe { - fmt.width = getcount(args, &arg.format.width); - fmt.precision = getcount(args, &arg.format.precision); + fmt.width = getcount(args, &arg.width); + fmt.precision = getcount(args, &arg.precision); } // Extract the correct argument @@ -1299,14 +1139,14 @@ unsafe fn run(fmt: &mut Formatter<'_>, arg: &rt::v1::Argument, args: &[ArgumentV let value = unsafe { args.get_unchecked(arg.position) }; // Then actually do some printing - (value.formatter)(value.value, fmt) + value.fmt(fmt) } -unsafe fn getcount(args: &[ArgumentV1<'_>], cnt: &rt::v1::Count) -> Option<usize> { +unsafe fn getcount(args: &[rt::Argument<'_>], cnt: &rt::Count) -> Option<usize> { match *cnt { - rt::v1::Count::Is(n) => Some(n), - rt::v1::Count::Implied => None, - rt::v1::Count::Param(i) => { + rt::Count::Is(n) => Some(n), + rt::Count::Implied => None, + rt::Count::Param(i) => { debug_assert!(i < args.len()); // SAFETY: cnt and args come from the same Arguments, // which guarantees this index is always within bounds. @@ -1388,7 +1228,7 @@ impl<'a> Formatter<'a> { /// } /// /// impl fmt::Display for Foo { - /// fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { /// // We need to remove "-" from the number output. /// let tmp = self.nb.abs().to_string(); /// @@ -1449,9 +1289,9 @@ impl<'a> Formatter<'a> { // is zero Some(min) if self.sign_aware_zero_pad() => { let old_fill = crate::mem::replace(&mut self.fill, '0'); - let old_align = crate::mem::replace(&mut self.align, rt::v1::Alignment::Right); + let old_align = crate::mem::replace(&mut self.align, rt::Alignment::Right); write_prefix(self, sign, prefix)?; - let post_padding = self.padding(min - width, rt::v1::Alignment::Right)?; + let post_padding = self.padding(min - width, Alignment::Right)?; self.buf.write_str(buf)?; post_padding.write(self)?; self.fill = old_fill; @@ -1460,7 +1300,7 @@ impl<'a> Formatter<'a> { } // Otherwise, the sign and prefix goes after the padding Some(min) => { - let post_padding = self.padding(min - width, rt::v1::Alignment::Right)?; + let post_padding = self.padding(min - width, Alignment::Right)?; write_prefix(self, sign, prefix)?; self.buf.write_str(buf)?; post_padding.write(self) @@ -1488,7 +1328,7 @@ impl<'a> Formatter<'a> { /// struct Foo; /// /// impl fmt::Display for Foo { - /// fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { /// formatter.pad("Foo") /// } /// } @@ -1535,7 +1375,7 @@ impl<'a> Formatter<'a> { // If we're under both the maximum and the minimum width, then fill // up the minimum width with the specified string + some alignment. else { - let align = rt::v1::Alignment::Left; + let align = Alignment::Left; let post_padding = self.padding(width - chars_count, align)?; self.buf.write_str(s)?; post_padding.write(self) @@ -1550,17 +1390,19 @@ impl<'a> Formatter<'a> { pub(crate) fn padding( &mut self, padding: usize, - default: rt::v1::Alignment, + default: Alignment, ) -> result::Result<PostPadding, Error> { let align = match self.align { - rt::v1::Alignment::Unknown => default, - _ => self.align, + rt::Alignment::Unknown => default, + rt::Alignment::Left => Alignment::Left, + rt::Alignment::Right => Alignment::Right, + rt::Alignment::Center => Alignment::Center, }; let (pre_pad, post_pad) = match align { - rt::v1::Alignment::Left => (0, padding), - rt::v1::Alignment::Right | rt::v1::Alignment::Unknown => (padding, 0), - rt::v1::Alignment::Center => (padding / 2, (padding + 1) / 2), + Alignment::Left => (0, padding), + Alignment::Right => (padding, 0), + Alignment::Center => (padding / 2, (padding + 1) / 2), }; for _ in 0..pre_pad { @@ -1573,14 +1415,17 @@ impl<'a> Formatter<'a> { /// Takes the formatted parts and applies the padding. /// Assumes that the caller already has rendered the parts with required precision, /// so that `self.precision` can be ignored. - fn pad_formatted_parts(&mut self, formatted: &numfmt::Formatted<'_>) -> Result { + /// + /// # Safety + /// + /// Any `numfmt::Part::Copy` parts in `formatted` must contain valid UTF-8. + unsafe fn pad_formatted_parts(&mut self, formatted: &numfmt::Formatted<'_>) -> Result { if let Some(mut width) = self.width { // for the sign-aware zero padding, we render the sign first and // behave as if we had no sign from the beginning. let mut formatted = formatted.clone(); let old_fill = self.fill; let old_align = self.align; - let mut align = old_align; if self.sign_aware_zero_pad() { // a sign always goes first let sign = formatted.sign; @@ -1589,19 +1434,22 @@ impl<'a> Formatter<'a> { // remove the sign from the formatted parts formatted.sign = ""; width = width.saturating_sub(sign.len()); - align = rt::v1::Alignment::Right; self.fill = '0'; - self.align = rt::v1::Alignment::Right; + self.align = rt::Alignment::Right; } // remaining parts go through the ordinary padding process. let len = formatted.len(); let ret = if width <= len { // no padding - self.write_formatted_parts(&formatted) + // SAFETY: Per the precondition. + unsafe { self.write_formatted_parts(&formatted) } } else { - let post_padding = self.padding(width - len, align)?; - self.write_formatted_parts(&formatted)?; + let post_padding = self.padding(width - len, Alignment::Right)?; + // SAFETY: Per the precondition. + unsafe { + self.write_formatted_parts(&formatted)?; + } post_padding.write(self) }; self.fill = old_fill; @@ -1609,20 +1457,20 @@ impl<'a> Formatter<'a> { ret } else { // this is the common case and we take a shortcut - self.write_formatted_parts(formatted) + // SAFETY: Per the precondition. + unsafe { self.write_formatted_parts(formatted) } } } - fn write_formatted_parts(&mut self, formatted: &numfmt::Formatted<'_>) -> Result { - fn write_bytes(buf: &mut dyn Write, s: &[u8]) -> Result { + /// # Safety + /// + /// Any `numfmt::Part::Copy` parts in `formatted` must contain valid UTF-8. + unsafe fn write_formatted_parts(&mut self, formatted: &numfmt::Formatted<'_>) -> Result { + unsafe fn write_bytes(buf: &mut dyn Write, s: &[u8]) -> Result { // SAFETY: This is used for `numfmt::Part::Num` and `numfmt::Part::Copy`. // It's safe to use for `numfmt::Part::Num` since every char `c` is between - // `b'0'` and `b'9'`, which means `s` is valid UTF-8. - // It's also probably safe in practice to use for `numfmt::Part::Copy(buf)` - // since `buf` should be plain ASCII, but it's possible for someone to pass - // in a bad value for `buf` into `numfmt::to_shortest_str` since it is a - // public function. - // FIXME: Determine whether this could result in UB. + // `b'0'` and `b'9'`, which means `s` is valid UTF-8. It's safe to use for + // `numfmt::Part::Copy` due to this function's precondition. buf.write_str(unsafe { str::from_utf8_unchecked(s) }) } @@ -1649,11 +1497,15 @@ impl<'a> Formatter<'a> { *c = b'0' + (v % 10) as u8; v /= 10; } - write_bytes(self.buf, &s[..len])?; + // SAFETY: Per the precondition. + unsafe { + write_bytes(self.buf, &s[..len])?; + } } - numfmt::Part::Copy(buf) => { + // SAFETY: Per the precondition. + numfmt::Part::Copy(buf) => unsafe { write_bytes(self.buf, buf)?; - } + }, } } Ok(()) @@ -1670,7 +1522,7 @@ impl<'a> Formatter<'a> { /// struct Foo; /// /// impl fmt::Display for Foo { - /// fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { /// formatter.write_str("Foo") /// // This is equivalent to: /// // write!(formatter, "Foo") @@ -1695,7 +1547,7 @@ impl<'a> Formatter<'a> { /// struct Foo(i32); /// /// impl fmt::Display for Foo { - /// fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { /// formatter.write_fmt(format_args!("Foo {}", self.0)) /// } /// } @@ -1730,7 +1582,7 @@ impl<'a> Formatter<'a> { /// struct Foo; /// /// impl fmt::Display for Foo { - /// fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { /// let c = formatter.fill(); /// if let Some(width) = formatter.width() { /// for _ in 0..width { @@ -1758,14 +1610,12 @@ impl<'a> Formatter<'a> { /// # Examples /// /// ``` - /// extern crate core; - /// /// use std::fmt::{self, Alignment}; /// /// struct Foo; /// /// impl fmt::Display for Foo { - /// fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { /// let s = if let Some(s) = formatter.align() { /// match s { /// Alignment::Left => "left", @@ -1788,10 +1638,10 @@ impl<'a> Formatter<'a> { #[stable(feature = "fmt_flags_align", since = "1.28.0")] pub fn align(&self) -> Option<Alignment> { match self.align { - rt::v1::Alignment::Left => Some(Alignment::Left), - rt::v1::Alignment::Right => Some(Alignment::Right), - rt::v1::Alignment::Center => Some(Alignment::Center), - rt::v1::Alignment::Unknown => None, + rt::Alignment::Left => Some(Alignment::Left), + rt::Alignment::Right => Some(Alignment::Right), + rt::Alignment::Center => Some(Alignment::Center), + rt::Alignment::Unknown => None, } } @@ -1805,7 +1655,7 @@ impl<'a> Formatter<'a> { /// struct Foo(i32); /// /// impl fmt::Display for Foo { - /// fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { /// if let Some(width) = formatter.width() { /// // If we received a width, we use it /// write!(formatter, "{:width$}", format!("Foo({})", self.0), width = width) @@ -1836,7 +1686,7 @@ impl<'a> Formatter<'a> { /// struct Foo(f32); /// /// impl fmt::Display for Foo { - /// fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { /// if let Some(precision) = formatter.precision() { /// // If we received a precision, we use it. /// write!(formatter, "Foo({1:.*})", precision, self.0) @@ -1866,7 +1716,7 @@ impl<'a> Formatter<'a> { /// struct Foo(i32); /// /// impl fmt::Display for Foo { - /// fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { /// if formatter.sign_plus() { /// write!(formatter, /// "Foo({}{})", @@ -1885,7 +1735,7 @@ impl<'a> Formatter<'a> { #[must_use] #[stable(feature = "fmt_flags", since = "1.5.0")] pub fn sign_plus(&self) -> bool { - self.flags & (1 << FlagV1::SignPlus as u32) != 0 + self.flags & (1 << rt::Flag::SignPlus as u32) != 0 } /// Determines if the `-` flag was specified. @@ -1898,7 +1748,7 @@ impl<'a> Formatter<'a> { /// struct Foo(i32); /// /// impl fmt::Display for Foo { - /// fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { /// if formatter.sign_minus() { /// // You want a minus sign? Have one! /// write!(formatter, "-Foo({})", self.0) @@ -1914,7 +1764,7 @@ impl<'a> Formatter<'a> { #[must_use] #[stable(feature = "fmt_flags", since = "1.5.0")] pub fn sign_minus(&self) -> bool { - self.flags & (1 << FlagV1::SignMinus as u32) != 0 + self.flags & (1 << rt::Flag::SignMinus as u32) != 0 } /// Determines if the `#` flag was specified. @@ -1927,7 +1777,7 @@ impl<'a> Formatter<'a> { /// struct Foo(i32); /// /// impl fmt::Display for Foo { - /// fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { /// if formatter.alternate() { /// write!(formatter, "Foo({})", self.0) /// } else { @@ -1942,7 +1792,7 @@ impl<'a> Formatter<'a> { #[must_use] #[stable(feature = "fmt_flags", since = "1.5.0")] pub fn alternate(&self) -> bool { - self.flags & (1 << FlagV1::Alternate as u32) != 0 + self.flags & (1 << rt::Flag::Alternate as u32) != 0 } /// Determines if the `0` flag was specified. @@ -1955,7 +1805,7 @@ impl<'a> Formatter<'a> { /// struct Foo(i32); /// /// impl fmt::Display for Foo { - /// fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, formatter: &mut fmt::Formatter<'_>) -> fmt::Result { /// assert!(formatter.sign_aware_zero_pad()); /// assert_eq!(formatter.width(), Some(4)); /// // We ignore the formatter's options. @@ -1968,17 +1818,17 @@ impl<'a> Formatter<'a> { #[must_use] #[stable(feature = "fmt_flags", since = "1.5.0")] pub fn sign_aware_zero_pad(&self) -> bool { - self.flags & (1 << FlagV1::SignAwareZeroPad as u32) != 0 + self.flags & (1 << rt::Flag::SignAwareZeroPad as u32) != 0 } // FIXME: Decide what public API we want for these two flags. // https://github.com/rust-lang/rust/issues/48584 fn debug_lower_hex(&self) -> bool { - self.flags & (1 << FlagV1::DebugLowerHex as u32) != 0 + self.flags & (1 << rt::Flag::DebugLowerHex as u32) != 0 } fn debug_upper_hex(&self) -> bool { - self.flags & (1 << FlagV1::DebugUpperHex as u32) != 0 + self.flags & (1 << rt::Flag::DebugUpperHex as u32) != 0 } /// Creates a [`DebugStruct`] builder designed to assist with creation of @@ -1999,7 +1849,7 @@ impl<'a> Formatter<'a> { /// } /// /// impl fmt::Debug for Foo { - /// fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { /// fmt.debug_struct("Foo") /// .field("bar", &self.bar) /// .field("baz", &self.baz) @@ -2157,7 +2007,7 @@ impl<'a> Formatter<'a> { /// struct Foo<T>(i32, String, PhantomData<T>); /// /// impl<T> fmt::Debug for Foo<T> { - /// fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { /// fmt.debug_tuple("Foo") /// .field(&self.0) /// .field(&self.1) @@ -2289,7 +2139,7 @@ impl<'a> Formatter<'a> { /// struct Foo(Vec<i32>); /// /// impl fmt::Debug for Foo { - /// fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { /// fmt.debug_list().entries(self.0.iter()).finish() /// } /// } @@ -2312,7 +2162,7 @@ impl<'a> Formatter<'a> { /// struct Foo(Vec<i32>); /// /// impl fmt::Debug for Foo { - /// fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { /// fmt.debug_set().entries(self.0.iter()).finish() /// } /// } @@ -2328,14 +2178,14 @@ impl<'a> Formatter<'a> { /// ```rust /// use std::fmt; /// - /// struct Arm<'a, L: 'a, R: 'a>(&'a (L, R)); - /// struct Table<'a, K: 'a, V: 'a>(&'a [(K, V)], V); + /// struct Arm<'a, L, R>(&'a (L, R)); + /// struct Table<'a, K, V>(&'a [(K, V)], V); /// /// impl<'a, L, R> fmt::Debug for Arm<'a, L, R> /// where /// L: 'a + fmt::Debug, R: 'a + fmt::Debug /// { - /// fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { /// L::fmt(&(self.0).0, fmt)?; /// fmt.write_str(" => ")?; /// R::fmt(&(self.0).1, fmt) @@ -2346,7 +2196,7 @@ impl<'a> Formatter<'a> { /// where /// K: 'a + fmt::Debug, V: 'a + fmt::Debug /// { - /// fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { /// fmt.debug_set() /// .entries(self.0.iter().map(Arm)) /// .entry(&Arm(&(format_args!("_"), &self.1))) @@ -2370,7 +2220,7 @@ impl<'a> Formatter<'a> { /// struct Foo(Vec<(String, i32)>); /// /// impl fmt::Debug for Foo { - /// fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result { + /// fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result { /// fmt.debug_map().entries(self.0.iter().map(|&(ref k, ref v)| (k, v))).finish() /// } /// } @@ -2429,6 +2279,7 @@ fmt_refs! { Debug, Display, Octal, Binary, LowerHex, UpperHex, LowerExp, UpperEx #[unstable(feature = "never_type", issue = "35121")] impl Debug for ! { + #[inline] fn fmt(&self, _: &mut Formatter<'_>) -> Result { *self } @@ -2436,6 +2287,7 @@ impl Debug for ! { #[unstable(feature = "never_type", issue = "35121")] impl Display for ! { + #[inline] fn fmt(&self, _: &mut Formatter<'_>) -> Result { *self } @@ -2538,13 +2390,13 @@ pub(crate) fn pointer_fmt_inner(ptr_addr: usize, f: &mut Formatter<'_>) -> Resul // or not to zero extend, and then unconditionally set it to get the // prefix. if f.alternate() { - f.flags |= 1 << (FlagV1::SignAwareZeroPad as u32); + f.flags |= 1 << (rt::Flag::SignAwareZeroPad as u32); if f.width.is_none() { f.width = Some((usize::BITS / 4) as usize + 2); } } - f.flags |= 1 << (FlagV1::Alternate as u32); + f.flags |= 1 << (rt::Flag::Alternate as u32); let ret = LowerHex::fmt(&ptr_addr, f); diff --git a/library/core/src/fmt/num.rs b/library/core/src/fmt/num.rs index d8365ae9b..4f42f73eb 100644 --- a/library/core/src/fmt/num.rs +++ b/library/core/src/fmt/num.rs @@ -52,8 +52,12 @@ impl_int! { i8 i16 i32 i64 i128 isize } impl_uint! { u8 u16 u32 u64 u128 usize } /// A type that represents a specific radix +/// +/// # Safety +/// +/// `digit` must return an ASCII character. #[doc(hidden)] -trait GenericRadix: Sized { +unsafe trait GenericRadix: Sized { /// The number of digits. const BASE: u8; @@ -129,7 +133,7 @@ struct UpperHex; macro_rules! radix { ($T:ident, $base:expr, $prefix:expr, $($x:pat => $conv:expr),+) => { - impl GenericRadix for $T { + unsafe impl GenericRadix for $T { const BASE: u8 = $base; const PREFIX: &'static str = $prefix; fn digit(x: u8) -> u8 { @@ -407,7 +411,7 @@ macro_rules! impl_Exp { let parts = &[ numfmt::Part::Copy(buf_slice), numfmt::Part::Zero(added_precision), - numfmt::Part::Copy(exp_slice) + numfmt::Part::Copy(exp_slice), ]; let sign = if !is_nonnegative { "-" @@ -416,8 +420,9 @@ macro_rules! impl_Exp { } else { "" }; - let formatted = numfmt::Formatted{sign, parts}; - f.pad_formatted_parts(&formatted) + let formatted = numfmt::Formatted { sign, parts }; + // SAFETY: `buf_slice` and `exp_slice` contain only ASCII characters. + unsafe { f.pad_formatted_parts(&formatted) } } $( diff --git a/library/core/src/fmt/rt.rs b/library/core/src/fmt/rt.rs new file mode 100644 index 000000000..d37888c27 --- /dev/null +++ b/library/core/src/fmt/rt.rs @@ -0,0 +1,212 @@ +#![allow(missing_debug_implementations)] +#![unstable(feature = "fmt_internals", reason = "internal to format_args!", issue = "none")] + +//! These are the lang items used by format_args!(). + +use super::*; + +#[lang = "format_placeholder"] +#[derive(Copy, Clone)] +pub struct Placeholder { + pub position: usize, + pub fill: char, + pub align: Alignment, + pub flags: u32, + pub precision: Count, + pub width: Count, +} + +impl Placeholder { + #[inline(always)] + pub const fn new( + position: usize, + fill: char, + align: Alignment, + flags: u32, + precision: Count, + width: Count, + ) -> Self { + Self { position, fill, align, flags, precision, width } + } +} + +#[lang = "format_alignment"] +#[derive(Copy, Clone, PartialEq, Eq)] +pub enum Alignment { + Left, + Right, + Center, + Unknown, +} + +/// Used by [width](https://doc.rust-lang.org/std/fmt/#width) +/// and [precision](https://doc.rust-lang.org/std/fmt/#precision) specifiers. +#[lang = "format_count"] +#[derive(Copy, Clone)] +pub enum Count { + /// Specified with a literal number, stores the value + Is(usize), + /// Specified using `$` and `*` syntaxes, stores the index into `args` + Param(usize), + /// Not specified + Implied, +} + +// This needs to match the order of flags in compiler/rustc_ast_lowering/src/format.rs. +#[derive(Copy, Clone)] +pub(super) enum Flag { + SignPlus, + SignMinus, + Alternate, + SignAwareZeroPad, + DebugLowerHex, + DebugUpperHex, +} + +/// This struct represents the generic "argument" which is taken by format_args!(). +/// It contains a function to format the given value. At compile time it is ensured that the +/// function and the value have the correct types, and then this struct is used to canonicalize +/// arguments to one type. +/// +/// Argument is essentially an optimized partially applied formatting function, +/// equivalent to `exists T.(&T, fn(&T, &mut Formatter<'_>) -> Result`. +#[lang = "format_argument"] +#[derive(Copy, Clone)] +pub struct Argument<'a> { + value: &'a Opaque, + formatter: fn(&Opaque, &mut Formatter<'_>) -> Result, +} + +#[rustc_diagnostic_item = "ArgumentMethods"] +impl<'a> Argument<'a> { + #[inline(always)] + fn new<'b, T>(x: &'b T, f: fn(&T, &mut Formatter<'_>) -> Result) -> Argument<'b> { + // SAFETY: `mem::transmute(x)` is safe because + // 1. `&'b T` keeps the lifetime it originated with `'b` + // (so as to not have an unbounded lifetime) + // 2. `&'b T` and `&'b Opaque` have the same memory layout + // (when `T` is `Sized`, as it is here) + // `mem::transmute(f)` is safe since `fn(&T, &mut Formatter<'_>) -> Result` + // and `fn(&Opaque, &mut Formatter<'_>) -> Result` have the same ABI + // (as long as `T` is `Sized`) + unsafe { Argument { formatter: mem::transmute(f), value: mem::transmute(x) } } + } + + #[inline(always)] + pub fn new_display<'b, T: Display>(x: &'b T) -> Argument<'_> { + Self::new(x, Display::fmt) + } + #[inline(always)] + pub fn new_debug<'b, T: Debug>(x: &'b T) -> Argument<'_> { + Self::new(x, Debug::fmt) + } + #[inline(always)] + pub fn new_octal<'b, T: Octal>(x: &'b T) -> Argument<'_> { + Self::new(x, Octal::fmt) + } + #[inline(always)] + pub fn new_lower_hex<'b, T: LowerHex>(x: &'b T) -> Argument<'_> { + Self::new(x, LowerHex::fmt) + } + #[inline(always)] + pub fn new_upper_hex<'b, T: UpperHex>(x: &'b T) -> Argument<'_> { + Self::new(x, UpperHex::fmt) + } + #[inline(always)] + pub fn new_pointer<'b, T: Pointer>(x: &'b T) -> Argument<'_> { + Self::new(x, Pointer::fmt) + } + #[inline(always)] + pub fn new_binary<'b, T: Binary>(x: &'b T) -> Argument<'_> { + Self::new(x, Binary::fmt) + } + #[inline(always)] + pub fn new_lower_exp<'b, T: LowerExp>(x: &'b T) -> Argument<'_> { + Self::new(x, LowerExp::fmt) + } + #[inline(always)] + pub fn new_upper_exp<'b, T: UpperExp>(x: &'b T) -> Argument<'_> { + Self::new(x, UpperExp::fmt) + } + #[inline(always)] + pub fn from_usize(x: &usize) -> Argument<'_> { + Self::new(x, USIZE_MARKER) + } + + #[inline(always)] + pub(super) fn fmt(&self, f: &mut Formatter<'_>) -> Result { + (self.formatter)(self.value, f) + } + + #[inline(always)] + pub(super) fn as_usize(&self) -> Option<usize> { + // We are type punning a bit here: USIZE_MARKER only takes an &usize but + // formatter takes an &Opaque. Rust understandably doesn't think we should compare + // the function pointers if they don't have the same signature, so we cast to + // usizes to tell it that we just want to compare addresses. + if self.formatter as usize == USIZE_MARKER as usize { + // SAFETY: The `formatter` field is only set to USIZE_MARKER if + // the value is a usize, so this is safe + Some(unsafe { *(self.value as *const _ as *const usize) }) + } else { + None + } + } + + /// Used by `format_args` when all arguments are gone after inlining, + /// when using `&[]` would incorrectly allow for a bigger lifetime. + /// + /// This fails without format argument inlining, and that shouldn't be different + /// when the argument is inlined: + /// + /// ```compile_fail,E0716 + /// let f = format_args!("{}", "a"); + /// println!("{f}"); + /// ``` + #[inline(always)] + pub fn none() -> [Self; 0] { + [] + } +} + +/// This struct represents the unsafety of constructing an `Arguments`. +/// It exists, rather than an unsafe function, in order to simplify the expansion +/// of `format_args!(..)` and reduce the scope of the `unsafe` block. +#[lang = "format_unsafe_arg"] +pub struct UnsafeArg { + _private: (), +} + +impl UnsafeArg { + /// See documentation where `UnsafeArg` is required to know when it is safe to + /// create and use `UnsafeArg`. + #[inline(always)] + pub unsafe fn new() -> Self { + Self { _private: () } + } +} + +extern "C" { + type Opaque; +} + +// This guarantees a single stable value for the function pointer associated with +// indices/counts in the formatting infrastructure. +// +// Note that a function defined as such would not be correct as functions are +// always tagged unnamed_addr with the current lowering to LLVM IR, so their +// address is not considered important to LLVM and as such the as_usize cast +// could have been miscompiled. In practice, we never call as_usize on non-usize +// containing data (as a matter of static generation of the formatting +// arguments), so this is merely an additional check. +// +// We primarily want to ensure that the function pointer at `USIZE_MARKER` has +// an address corresponding *only* to functions that also take `&usize` as their +// first argument. The read_volatile here ensures that we can safely ready out a +// usize from the passed reference and that this address does not point at a +// non-usize taking function. +static USIZE_MARKER: fn(&usize, &mut Formatter<'_>) -> Result = |ptr, _| { + // SAFETY: ptr is a reference + let _v: usize = unsafe { crate::ptr::read_volatile(ptr) }; + loop {} +}; diff --git a/library/core/src/fmt/rt/v1.rs b/library/core/src/fmt/rt/v1.rs deleted file mode 100644 index 6d70796f7..000000000 --- a/library/core/src/fmt/rt/v1.rs +++ /dev/null @@ -1,63 +0,0 @@ -//! This is an internal module used by the ifmt! runtime. These structures are -//! emitted to static arrays to precompile format strings ahead of time. -//! -//! These definitions are similar to their `ct` equivalents, but differ in that -//! these can be statically allocated and are slightly optimized for the runtime -#![allow(missing_debug_implementations)] - -#[lang = "format_placeholder"] -#[derive(Copy, Clone)] -// FIXME: Rename this to Placeholder -pub struct Argument { - pub position: usize, - pub format: FormatSpec, -} - -#[derive(Copy, Clone)] -pub struct FormatSpec { - pub fill: char, - pub align: Alignment, - pub flags: u32, - pub precision: Count, - pub width: Count, -} - -impl Argument { - #[inline(always)] - pub const fn new( - position: usize, - fill: char, - align: Alignment, - flags: u32, - precision: Count, - width: Count, - ) -> Self { - Self { position, format: FormatSpec { fill, align, flags, precision, width } } - } -} - -/// Possible alignments that can be requested as part of a formatting directive. -#[lang = "format_alignment"] -#[derive(Copy, Clone, PartialEq, Eq)] -pub enum Alignment { - /// Indication that contents should be left-aligned. - Left, - /// Indication that contents should be right-aligned. - Right, - /// Indication that contents should be center-aligned. - Center, - /// No alignment was requested. - Unknown, -} - -/// Used by [width](https://doc.rust-lang.org/std/fmt/#width) and [precision](https://doc.rust-lang.org/std/fmt/#precision) specifiers. -#[lang = "format_count"] -#[derive(Copy, Clone)] -pub enum Count { - /// Specified with a literal number, stores the value - Is(usize), - /// Specified using `$` and `*` syntaxes, stores the index into `args` - Param(usize), - /// Not specified - Implied, -} diff --git a/library/core/src/future/into_future.rs b/library/core/src/future/into_future.rs index 649b43387..38c654e76 100644 --- a/library/core/src/future/into_future.rs +++ b/library/core/src/future/into_future.rs @@ -99,6 +99,7 @@ use crate::future::Future; /// } /// ``` #[stable(feature = "into_future", since = "1.64.0")] +#[rustc_diagnostic_item = "IntoFuture"] pub trait IntoFuture { /// The output that the future will produce on completion. #[stable(feature = "into_future", since = "1.64.0")] diff --git a/library/core/src/future/join.rs b/library/core/src/future/join.rs index 35f0dea06..3f35179dd 100644 --- a/library/core/src/future/join.rs +++ b/library/core/src/future/join.rs @@ -4,7 +4,7 @@ use crate::cell::UnsafeCell; use crate::future::{poll_fn, Future}; use crate::mem; use crate::pin::Pin; -use crate::task::{Context, Poll}; +use crate::task::{ready, Context, Poll}; /// Polls multiple futures simultaneously, returning a tuple /// of all results once complete. @@ -118,7 +118,7 @@ macro join_internal { fut }) }; - // Despite how tempting it may be to `let () = fut.poll(cx).ready()?;` + // Despite how tempting it may be to `let () = ready!(fut.poll(cx));` // doing so would defeat the point of `join!`: to start polling eagerly all // of the futures, to allow parallelizing the waits. done &= fut.poll(cx).is_ready(); @@ -180,7 +180,7 @@ impl<F: Future> Future for MaybeDone<F> { // Do not mix match ergonomics with unsafe. match *self.as_mut().get_unchecked_mut() { MaybeDone::Future(ref mut f) => { - let val = Pin::new_unchecked(f).poll(cx).ready()?; + let val = ready!(Pin::new_unchecked(f).poll(cx)); self.set(Self::Done(val)); } MaybeDone::Done(_) => {} diff --git a/library/core/src/future/mod.rs b/library/core/src/future/mod.rs index 04f02d47f..089493d37 100644 --- a/library/core/src/future/mod.rs +++ b/library/core/src/future/mod.rs @@ -66,11 +66,3 @@ pub unsafe fn get_context<'a, 'b>(cx: ResumeTy) -> &'a mut Context<'b> { // that fulfills all the requirements for a mutable reference. unsafe { &mut *cx.0.as_ptr().cast() } } - -#[doc(hidden)] -#[unstable(feature = "gen_future", issue = "50547")] -#[inline] -#[cfg_attr(bootstrap, lang = "identity_future")] -pub const fn identity_future<O, Fut: Future<Output = O>>(f: Fut) -> Fut { - f -} diff --git a/library/core/src/hash/mod.rs b/library/core/src/hash/mod.rs index 4e7bae7bc..794a57f09 100644 --- a/library/core/src/hash/mod.rs +++ b/library/core/src/hash/mod.rs @@ -86,8 +86,7 @@ #![stable(feature = "rust1", since = "1.0.0")] use crate::fmt; -use crate::intrinsics::const_eval_select; -use crate::marker::{self, Destruct}; +use crate::marker; #[stable(feature = "rust1", since = "1.0.0")] #[allow(deprecated)] @@ -184,7 +183,6 @@ mod sip; /// [impl]: ../../std/primitive.str.html#impl-Hash-for-str #[stable(feature = "rust1", since = "1.0.0")] #[rustc_diagnostic_item = "Hash"] -#[const_trait] pub trait Hash { /// Feeds this value into the given [`Hasher`]. /// @@ -199,7 +197,7 @@ pub trait Hash { /// println!("Hash is {:x}!", hasher.finish()); /// ``` #[stable(feature = "rust1", since = "1.0.0")] - fn hash<H: ~const Hasher>(&self, state: &mut H); + fn hash<H: Hasher>(&self, state: &mut H); /// Feeds a slice of this type into the given [`Hasher`]. /// @@ -236,25 +234,13 @@ pub trait Hash { /// [`hash`]: Hash::hash /// [`hash_slice`]: Hash::hash_slice #[stable(feature = "hash_slice", since = "1.3.0")] - fn hash_slice<H: ~const Hasher>(data: &[Self], state: &mut H) + fn hash_slice<H: Hasher>(data: &[Self], state: &mut H) where Self: Sized, { - //FIXME(const_trait_impl): revert to only a for loop - fn rt<T: Hash, H: Hasher>(data: &[T], state: &mut H) { - for piece in data { - piece.hash(state) - } - } - const fn ct<T: ~const Hash, H: ~const Hasher>(data: &[T], state: &mut H) { - let mut i = 0; - while i < data.len() { - data[i].hash(state); - i += 1; - } + for piece in data { + piece.hash(state) } - // SAFETY: same behavior, CT just uses while instead of for - unsafe { const_eval_select((data, state), ct, rt) }; } } @@ -327,7 +313,6 @@ pub use macros::Hash; /// [`write_u8`]: Hasher::write_u8 /// [`write_u32`]: Hasher::write_u32 #[stable(feature = "rust1", since = "1.0.0")] -#[const_trait] pub trait Hasher { /// Returns the hash value for the values written so far. /// @@ -573,8 +558,7 @@ pub trait Hasher { } #[stable(feature = "indirect_hasher_impl", since = "1.22.0")] -#[rustc_const_unstable(feature = "const_hash", issue = "104061")] -impl<H: ~const Hasher + ?Sized> const Hasher for &mut H { +impl<H: Hasher + ?Sized> Hasher for &mut H { fn finish(&self) -> u64 { (**self).finish() } @@ -654,7 +638,6 @@ impl<H: ~const Hasher + ?Sized> const Hasher for &mut H { /// [`build_hasher`]: BuildHasher::build_hasher /// [`HashMap`]: ../../std/collections/struct.HashMap.html #[stable(since = "1.7.0", feature = "build_hasher")] -#[const_trait] pub trait BuildHasher { /// Type of the hasher that will be created. #[stable(since = "1.7.0", feature = "build_hasher")] @@ -691,8 +674,6 @@ pub trait BuildHasher { /// # Example /// /// ``` - /// #![feature(build_hasher_simple_hash_one)] - /// /// use std::cmp::{max, min}; /// use std::hash::{BuildHasher, Hash, Hasher}; /// struct OrderAmbivalentPair<T: Ord>(T, T); @@ -714,11 +695,11 @@ pub trait BuildHasher { /// bh.hash_one(&OrderAmbivalentPair(2, 10)) /// ); /// ``` - #[unstable(feature = "build_hasher_simple_hash_one", issue = "86161")] - fn hash_one<T: ~const Hash + ~const Destruct>(&self, x: T) -> u64 + #[stable(feature = "build_hasher_simple_hash_one", since = "1.71.0")] + fn hash_one<T: Hash>(&self, x: T) -> u64 where Self: Sized, - Self::Hasher: ~const Hasher + ~const Destruct, + Self::Hasher: Hasher, { let mut hasher = self.build_hasher(); x.hash(&mut hasher); @@ -782,8 +763,7 @@ impl<H> fmt::Debug for BuildHasherDefault<H> { } #[stable(since = "1.7.0", feature = "build_hasher")] -#[rustc_const_unstable(feature = "const_hash", issue = "104061")] -impl<H: ~const Default + Hasher> const BuildHasher for BuildHasherDefault<H> { +impl<H: Default + Hasher> BuildHasher for BuildHasherDefault<H> { type Hasher = H; fn build_hasher(&self) -> H { @@ -799,8 +779,7 @@ impl<H> Clone for BuildHasherDefault<H> { } #[stable(since = "1.7.0", feature = "build_hasher")] -#[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] -impl<H> const Default for BuildHasherDefault<H> { +impl<H> Default for BuildHasherDefault<H> { fn default() -> BuildHasherDefault<H> { BuildHasherDefault(marker::PhantomData) } @@ -825,15 +804,14 @@ mod impls { macro_rules! impl_write { ($(($ty:ident, $meth:ident),)*) => {$( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_hash", issue = "104061")] - impl const Hash for $ty { + impl Hash for $ty { #[inline] - fn hash<H: ~const Hasher>(&self, state: &mut H) { + fn hash<H: Hasher>(&self, state: &mut H) { state.$meth(*self) } #[inline] - fn hash_slice<H: ~const Hasher>(data: &[$ty], state: &mut H) { + fn hash_slice<H: Hasher>(data: &[$ty], state: &mut H) { let newlen = mem::size_of_val(data); let ptr = data.as_ptr() as *const u8; // SAFETY: `ptr` is valid and aligned, as this macro is only used @@ -862,37 +840,33 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_hash", issue = "104061")] - impl const Hash for bool { + impl Hash for bool { #[inline] - fn hash<H: ~const Hasher>(&self, state: &mut H) { + fn hash<H: Hasher>(&self, state: &mut H) { state.write_u8(*self as u8) } } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_hash", issue = "104061")] - impl const Hash for char { + impl Hash for char { #[inline] - fn hash<H: ~const Hasher>(&self, state: &mut H) { + fn hash<H: Hasher>(&self, state: &mut H) { state.write_u32(*self as u32) } } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_hash", issue = "104061")] - impl const Hash for str { + impl Hash for str { #[inline] - fn hash<H: ~const Hasher>(&self, state: &mut H) { + fn hash<H: Hasher>(&self, state: &mut H) { state.write_str(self); } } #[stable(feature = "never_hash", since = "1.29.0")] - #[rustc_const_unstable(feature = "const_hash", issue = "104061")] - impl const Hash for ! { + impl Hash for ! { #[inline] - fn hash<H: ~const Hasher>(&self, _: &mut H) { + fn hash<H: Hasher>(&self, _: &mut H) { *self } } @@ -900,10 +874,9 @@ mod impls { macro_rules! impl_hash_tuple { () => ( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_hash", issue = "104061")] - impl const Hash for () { + impl Hash for () { #[inline] - fn hash<H: ~const Hasher>(&self, _state: &mut H) {} + fn hash<H: Hasher>(&self, _state: &mut H) {} } ); @@ -911,11 +884,10 @@ mod impls { maybe_tuple_doc! { $($name)+ @ #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_hash", issue = "104061")] - impl<$($name: ~const Hash),+> const Hash for ($($name,)+) where last_type!($($name,)+): ?Sized { + impl<$($name: Hash),+> Hash for ($($name,)+) where last_type!($($name,)+): ?Sized { #[allow(non_snake_case)] #[inline] - fn hash<S: ~const Hasher>(&self, state: &mut S) { + fn hash<S: Hasher>(&self, state: &mut S) { let ($(ref $name,)+) = *self; $($name.hash(state);)+ } @@ -958,29 +930,26 @@ mod impls { impl_hash_tuple! { T B C D E F G H I J K L } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_hash", issue = "104061")] - impl<T: ~const Hash> const Hash for [T] { + impl<T: Hash> Hash for [T] { #[inline] - fn hash<H: ~const Hasher>(&self, state: &mut H) { + fn hash<H: Hasher>(&self, state: &mut H) { state.write_length_prefix(self.len()); Hash::hash_slice(self, state) } } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_hash", issue = "104061")] - impl<T: ?Sized + ~const Hash> const Hash for &T { + impl<T: ?Sized + Hash> Hash for &T { #[inline] - fn hash<H: ~const Hasher>(&self, state: &mut H) { + fn hash<H: Hasher>(&self, state: &mut H) { (**self).hash(state); } } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_hash", issue = "104061")] - impl<T: ?Sized + ~const Hash> const Hash for &mut T { + impl<T: ?Sized + Hash> Hash for &mut T { #[inline] - fn hash<H: ~const Hasher>(&self, state: &mut H) { + fn hash<H: Hasher>(&self, state: &mut H) { (**self).hash(state); } } diff --git a/library/core/src/hash/sip.rs b/library/core/src/hash/sip.rs index 7f8287bf5..6b9f2e842 100644 --- a/library/core/src/hash/sip.rs +++ b/library/core/src/hash/sip.rs @@ -118,7 +118,7 @@ macro_rules! load_int_le { /// Safety: this performs unchecked indexing of `buf` at `start..start+len`, so /// that must be in-bounds. #[inline] -const unsafe fn u8to64_le(buf: &[u8], start: usize, len: usize) -> u64 { +unsafe fn u8to64_le(buf: &[u8], start: usize, len: usize) -> u64 { debug_assert!(len < 8); let mut i = 0; // current byte index (from LSB) in the output u64 let mut out = 0; @@ -225,8 +225,7 @@ impl<S: Sip> Hasher<S> { } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_hash", issue = "104061")] -impl const super::Hasher for SipHasher { +impl super::Hasher for SipHasher { #[inline] fn write(&mut self, msg: &[u8]) { self.0.hasher.write(msg) @@ -244,8 +243,7 @@ impl const super::Hasher for SipHasher { } #[unstable(feature = "hashmap_internals", issue = "none")] -#[rustc_const_unstable(feature = "const_hash", issue = "104061")] -impl const super::Hasher for SipHasher13 { +impl super::Hasher for SipHasher13 { #[inline] fn write(&mut self, msg: &[u8]) { self.hasher.write(msg) @@ -262,7 +260,7 @@ impl const super::Hasher for SipHasher13 { } } -impl<S: ~const Sip> const super::Hasher for Hasher<S> { +impl<S: Sip> super::Hasher for Hasher<S> { // Note: no integer hashing methods (`write_u*`, `write_i*`) are defined // for this type. We could add them, copy the `short_write` implementation // in librustc_data_structures/sip128.rs, and add `write_u*`/`write_i*` @@ -342,7 +340,7 @@ impl<S: ~const Sip> const super::Hasher for Hasher<S> { } } -impl<S: Sip> const Clone for Hasher<S> { +impl<S: Sip> Clone for Hasher<S> { #[inline] fn clone(&self) -> Hasher<S> { Hasher { @@ -366,7 +364,6 @@ impl<S: Sip> Default for Hasher<S> { } #[doc(hidden)] -#[const_trait] trait Sip { fn c_rounds(_: &mut State); fn d_rounds(_: &mut State); @@ -375,7 +372,7 @@ trait Sip { #[derive(Debug, Clone, Default)] struct Sip13Rounds; -impl const Sip for Sip13Rounds { +impl Sip for Sip13Rounds { #[inline] fn c_rounds(state: &mut State) { compress!(state); @@ -392,7 +389,7 @@ impl const Sip for Sip13Rounds { #[derive(Debug, Clone, Default)] struct Sip24Rounds; -impl const Sip for Sip24Rounds { +impl Sip for Sip24Rounds { #[inline] fn c_rounds(state: &mut State) { compress!(state); diff --git a/library/core/src/hint.rs b/library/core/src/hint.rs index a20556577..75c104ce2 100644 --- a/library/core/src/hint.rs +++ b/library/core/src/hint.rs @@ -73,8 +73,8 @@ use crate::intrinsics; /// ``` /// /// While using `unreachable_unchecked()` is perfectly sound in the following -/// example, the compiler is able to prove that a division by zero is not -/// possible. Benchmarking reveals that `unreachable_unchecked()` provides +/// example, as the compiler is able to prove that a division by zero is not +/// possible, benchmarking reveals that `unreachable_unchecked()` provides /// no benefit over using [`unreachable!`], while the latter does not introduce /// the possibility of Undefined Behavior. /// @@ -217,17 +217,14 @@ pub fn spin_loop() { /// Note however, that `black_box` is only (and can only be) provided on a "best-effort" basis. The /// extent to which it can block optimisations may vary depending upon the platform and code-gen /// backend used. Programs cannot rely on `black_box` for *correctness*, beyond it behaving as the -/// identity function. +/// identity function. As such, it **must not be relied upon to control critical program behavior.** +/// This _immediately_ precludes any direct use of this function for cryptographic or security +/// purposes. /// /// [`std::convert::identity`]: crate::convert::identity /// /// # When is this useful? /// -/// First and foremost: `black_box` does _not_ guarantee any exact behavior and, in some cases, may -/// do nothing at all. As such, it **must not be relied upon to control critical program behavior.** -/// This _immediately_ precludes any direct use of this function for cryptographic or security -/// purposes. -/// /// While not suitable in those mission-critical cases, `black_box`'s functionality can generally be /// relied upon for benchmarking, and should be used there. It will try to ensure that the /// compiler doesn't optimize away part of the intended test code based on context. For diff --git a/library/core/src/internal_macros.rs b/library/core/src/internal_macros.rs index 5d4c9ba73..5774107f5 100644 --- a/library/core/src/internal_macros.rs +++ b/library/core/src/internal_macros.rs @@ -1,23 +1,10 @@ // implements the unary operator "op &T" // based on "op T" where T is expected to be `Copy`able macro_rules! forward_ref_unop { - (impl const $imp:ident, $method:ident for $t:ty) => { - forward_ref_unop!(impl const $imp, $method for $t, + (impl $imp:ident, $method:ident for $t:ty) => { + forward_ref_unop!(impl $imp, $method for $t, #[stable(feature = "rust1", since = "1.0.0")]); }; - // Equivalent to the non-const version, with the addition of `rustc_const_unstable` - (impl const $imp:ident, $method:ident for $t:ty, #[$attr:meta]) => { - #[$attr] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const $imp for &$t { - type Output = <$t as $imp>::Output; - - #[inline] - fn $method(self) -> <$t as $imp>::Output { - $imp::$method(*self) - } - } - }; (impl $imp:ident, $method:ident for $t:ty, #[$attr:meta]) => { #[$attr] impl $imp for &$t { @@ -34,45 +21,10 @@ macro_rules! forward_ref_unop { // implements binary operators "&T op U", "T op &U", "&T op &U" // based on "T op U" where T and U are expected to be `Copy`able macro_rules! forward_ref_binop { - (impl const $imp:ident, $method:ident for $t:ty, $u:ty) => { - forward_ref_binop!(impl const $imp, $method for $t, $u, + (impl $imp:ident, $method:ident for $t:ty, $u:ty) => { + forward_ref_binop!(impl $imp, $method for $t, $u, #[stable(feature = "rust1", since = "1.0.0")]); }; - // Equivalent to the non-const version, with the addition of `rustc_const_unstable` - (impl const $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => { - #[$attr] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl<'a> const $imp<$u> for &'a $t { - type Output = <$t as $imp<$u>>::Output; - - #[inline] - fn $method(self, other: $u) -> <$t as $imp<$u>>::Output { - $imp::$method(*self, other) - } - } - - #[$attr] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const $imp<&$u> for $t { - type Output = <$t as $imp<$u>>::Output; - - #[inline] - fn $method(self, other: &$u) -> <$t as $imp<$u>>::Output { - $imp::$method(self, *other) - } - } - - #[$attr] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const $imp<&$u> for &$t { - type Output = <$t as $imp<$u>>::Output; - - #[inline] - fn $method(self, other: &$u) -> <$t as $imp<$u>>::Output { - $imp::$method(*self, *other) - } - } - }; (impl $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => { #[$attr] impl<'a> $imp<$u> for &'a $t { @@ -113,21 +65,6 @@ macro_rules! forward_ref_op_assign { forward_ref_op_assign!(impl $imp, $method for $t, $u, #[stable(feature = "op_assign_builtins_by_ref", since = "1.22.0")]); }; - (impl const $imp:ident, $method:ident for $t:ty, $u:ty) => { - forward_ref_op_assign!(impl const $imp, $method for $t, $u, - #[stable(feature = "op_assign_builtins_by_ref", since = "1.22.0")]); - }; - // Equivalent to the non-const version, with the addition of `rustc_const_unstable` - (impl const $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => { - #[$attr] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const $imp<&$u> for $t { - #[inline] - fn $method(&mut self, other: &$u) { - $imp::$method(self, *other); - } - } - }; (impl $imp:ident, $method:ident for $t:ty, $u:ty, #[$attr:meta]) => { #[$attr] impl $imp<&$u> for $t { diff --git a/library/core/src/intrinsics.rs b/library/core/src/intrinsics.rs index a7c100e1b..f5c5dd29f 100644 --- a/library/core/src/intrinsics.rs +++ b/library/core/src/intrinsics.rs @@ -1187,7 +1187,7 @@ extern "rust-intrinsic" { /// Below are common applications of `transmute` which can be replaced with safer /// constructs. /// - /// Turning raw bytes (`&[u8]`) into `u32`, `f64`, etc.: + /// Turning raw bytes (`[u8; SZ]`) into `u32`, `f64`, etc.: /// /// ``` /// let raw_bytes = [0x78, 0x56, 0x34, 0x12]; @@ -1376,6 +1376,20 @@ extern "rust-intrinsic" { #[rustc_nounwind] pub fn transmute<Src, Dst>(src: Src) -> Dst; + /// Like [`transmute`], but even less checked at compile-time: rather than + /// giving an error for `size_of::<Src>() != size_of::<Dst>()`, it's + /// **Undefined Behaviour** at runtime. + /// + /// Prefer normal `transmute` where possible, for the extra checking, since + /// both do exactly the same thing at runtime, if they both compile. + /// + /// This is not expected to ever be exposed directly to users, rather it + /// may eventually be exposed through some more-constrained API. + #[cfg(not(bootstrap))] + #[rustc_const_stable(feature = "const_transmute", since = "1.56.0")] + #[rustc_nounwind] + pub fn transmute_unchecked<Src, Dst>(src: Src) -> Dst; + /// Returns `true` if the actual type given as `T` requires drop /// glue; returns `false` if the actual type provided for `T` /// implements `Copy`. @@ -1399,6 +1413,10 @@ extern "rust-intrinsic" { /// This is implemented as an intrinsic to avoid converting to and from an /// integer, since the conversion would throw away aliasing information. /// + /// This can only be used with `Ptr` as a raw pointer type (`*mut` or `*const`) + /// to a `Sized` pointee and with `Delta` as `usize` or `isize`. Any other + /// instantiations may arbitrarily misbehave, and that's *not* a compiler bug. + /// /// # Safety /// /// Both the starting and resulting pointer must be either in bounds or one @@ -1407,6 +1425,14 @@ extern "rust-intrinsic" { /// returned value will result in undefined behavior. /// /// The stabilized version of this intrinsic is [`pointer::offset`]. + #[cfg(not(bootstrap))] + #[must_use = "returns a new pointer rather than modifying its argument"] + #[rustc_const_stable(feature = "const_ptr_offset", since = "1.61.0")] + #[rustc_nounwind] + pub fn offset<Ptr, Delta>(dst: Ptr, offset: Delta) -> Ptr; + + /// The bootstrap version of this is more restricted. + #[cfg(bootstrap)] #[must_use = "returns a new pointer rather than modifying its argument"] #[rustc_const_stable(feature = "const_ptr_offset", since = "1.61.0")] #[rustc_nounwind] @@ -1797,14 +1823,12 @@ extern "rust-intrinsic" { /// with an even least significant digit. /// /// This intrinsic does not have a stable counterpart. - #[cfg(not(bootstrap))] #[rustc_nounwind] pub fn roundevenf32(x: f32) -> f32; /// Returns the nearest integer to an `f64`. Rounds half-way cases to the number /// with an even least significant digit. /// /// This intrinsic does not have a stable counterpart. - #[cfg(not(bootstrap))] #[rustc_nounwind] pub fn roundevenf64(x: f64) -> f64; @@ -2233,13 +2257,23 @@ extern "rust-intrinsic" { /// This is an implementation detail of [`crate::ptr::read`] and should /// not be used anywhere else. See its comments for why this exists. /// - /// This intrinsic can *only* be called where the argument is a local without - /// projections (`read_via_copy(p)`, not `read_via_copy(*p)`) so that it + /// This intrinsic can *only* be called where the pointer is a local without + /// projections (`read_via_copy(ptr)`, not `read_via_copy(*ptr)`) so that it /// trivially obeys runtime-MIR rules about derefs in operands. + #[rustc_const_stable(feature = "const_ptr_read", since = "1.71.0")] + #[rustc_nounwind] + pub fn read_via_copy<T>(ptr: *const T) -> T; + + /// This is an implementation detail of [`crate::ptr::write`] and should + /// not be used anywhere else. See its comments for why this exists. + /// + /// This intrinsic can *only* be called where the pointer is a local without + /// projections (`write_via_move(ptr, x)`, not `write_via_move(*ptr, x)`) so + /// that it trivially obeys runtime-MIR rules about derefs in operands. #[cfg(not(bootstrap))] - #[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")] + #[rustc_const_unstable(feature = "const_ptr_write", issue = "86302")] #[rustc_nounwind] - pub fn read_via_copy<T>(p: *const T) -> T; + pub fn write_via_move<T>(ptr: *mut T, value: T); /// Returns the value of the discriminant for the variant in 'v'; /// if `T` has no discriminant, returns `0`. @@ -2444,7 +2478,6 @@ extern "rust-intrinsic" { /// This method creates a pointer to any `Some` value. If the argument is /// `None`, an invalid within-bounds pointer (that is still acceptable for /// constructing an empty slice) is returned. - #[cfg(not(bootstrap))] #[rustc_nounwind] pub fn option_payload_ptr<T>(arg: *const Option<T>) -> *const T; } @@ -2460,7 +2493,7 @@ extern "rust-intrinsic" { /// This macro should be called as `assert_unsafe_precondition!([Generics](name: Type) => Expression)` /// where the names specified will be moved into the macro as captured variables, and defines an item /// to call `const_eval_select` on. The tokens inside the square brackets are used to denote generics -/// for the function declaractions and can be omitted if there is no generics. +/// for the function declarations and can be omitted if there is no generics. /// /// # Safety /// @@ -2490,6 +2523,7 @@ macro_rules! assert_unsafe_precondition { } } #[allow(non_snake_case)] + #[inline] const fn comptime$(<$($tt)*>)?($(_:$ty),*) {} ::core::intrinsics::const_eval_select(($($i,)*), comptime, runtime); @@ -2519,7 +2553,9 @@ pub(crate) fn is_valid_allocation_size<T>(len: usize) -> bool { pub(crate) fn is_nonoverlapping<T>(src: *const T, dst: *const T, count: usize) -> bool { let src_usize = src.addr(); let dst_usize = dst.addr(); - let size = mem::size_of::<T>().checked_mul(count).unwrap(); + let size = mem::size_of::<T>() + .checked_mul(count) + .expect("is_nonoverlapping: `size_of::<T>() * count` overflows a usize"); let diff = if src_usize > dst_usize { src_usize - dst_usize } else { dst_usize - src_usize }; // If the absolute distance between the ptrs is at least as big as the size of the buffer, // they do not overlap. @@ -2717,7 +2753,7 @@ pub const unsafe fn copy<T>(src: *const T, dst: *mut T, count: usize) { // SAFETY: the safety contract for `copy` must be upheld by the caller. unsafe { assert_unsafe_precondition!( - "ptr::copy requires that both pointer arguments are aligned aligned and non-null", + "ptr::copy requires that both pointer arguments are aligned and non-null", [T](src: *const T, dst: *mut T) => is_aligned_and_not_null(src) && is_aligned_and_not_null(dst) ); @@ -2796,3 +2832,24 @@ pub const unsafe fn write_bytes<T>(dst: *mut T, val: u8, count: usize) { write_bytes(dst, val, count) } } + +/// Polyfill for bootstrap +#[cfg(bootstrap)] +pub const unsafe fn transmute_unchecked<Src, Dst>(src: Src) -> Dst { + use crate::mem::*; + // SAFETY: It's a transmute -- the caller promised it's fine. + unsafe { transmute_copy(&ManuallyDrop::new(src)) } +} + +/// Polyfill for bootstrap +#[cfg(bootstrap)] +pub const unsafe fn write_via_move<T>(ptr: *mut T, value: T) { + use crate::mem::*; + // SAFETY: the caller must guarantee that `dst` is valid for writes. + // `dst` cannot overlap `src` because the caller has mutable access + // to `dst` while `src` is owned by this function. + unsafe { + copy_nonoverlapping::<T>(&value, ptr, 1); + forget(value); + } +} diff --git a/library/core/src/intrinsics/mir.rs b/library/core/src/intrinsics/mir.rs index 45498a54b..5944a0de1 100644 --- a/library/core/src/intrinsics/mir.rs +++ b/library/core/src/intrinsics/mir.rs @@ -15,7 +15,6 @@ //! ```rust //! #![feature(core_intrinsics, custom_mir)] //! -//! extern crate core; //! use core::intrinsics::mir::*; //! //! #[custom_mir(dialect = "built")] @@ -65,7 +64,6 @@ //! ```rust //! #![feature(core_intrinsics, custom_mir)] //! -//! extern crate core; //! use core::intrinsics::mir::*; //! //! #[custom_mir(dialect = "built")] @@ -230,7 +228,7 @@ //! //! - Operands implicitly convert to `Use` rvalues. //! - `&`, `&mut`, `addr_of!`, and `addr_of_mut!` all work to create their associated rvalue. -//! - [`Discriminant`] and [`Len`] have associated functions. +//! - [`Discriminant`], [`Len`], and [`CopyForDeref`] have associated functions. //! - Unary and binary operations use their normal Rust syntax - `a * b`, `!c`, etc. //! - The binary operation `Offset` can be created via [`Offset`]. //! - Checked binary operations are represented by wrapping the associated binop in [`Checked`]. @@ -265,6 +263,7 @@ pub struct BasicBlock; macro_rules! define { ($name:literal, $( #[ $meta:meta ] )* fn $($sig:tt)*) => { #[rustc_diagnostic_item = $name] + #[inline] $( #[ $meta ] )* pub fn $($sig)* { panic!() } } @@ -280,6 +279,7 @@ define!("mir_storage_dead", fn StorageDead<T>(local: T)); define!("mir_deinit", fn Deinit<T>(place: T)); define!("mir_checked", fn Checked<T>(binop: T) -> (T, bool)); define!("mir_len", fn Len<T>(place: T) -> usize); +define!("mir_copy_for_deref", fn CopyForDeref<T>(place: T) -> T); define!("mir_retag", fn Retag<T>(place: T)); define!("mir_move", fn Move<T>(place: T) -> T); define!("mir_static", fn Static<T>(s: T) -> &'static T); @@ -317,7 +317,6 @@ define!( /// ```rust /// #![feature(custom_mir, core_intrinsics)] /// - /// extern crate core; /// use core::intrinsics::mir::*; /// /// #[custom_mir(dialect = "built")] diff --git a/library/core/src/iter/adapters/chain.rs b/library/core/src/iter/adapters/chain.rs index 75727c3a2..26aa959e6 100644 --- a/library/core/src/iter/adapters/chain.rs +++ b/library/core/src/iter/adapters/chain.rs @@ -15,7 +15,7 @@ use crate::ops::Try; /// /// let a1 = [1, 2, 3]; /// let a2 = [4, 5, 6]; -/// let iter: Chain<Iter<_>, Iter<_>> = a1.iter().chain(a2.iter()); +/// let iter: Chain<Iter<'_, _>, Iter<'_, _>> = a1.iter().chain(a2.iter()); /// ``` #[derive(Clone, Debug)] #[must_use = "iterators are lazy and do nothing unless consumed"] diff --git a/library/core/src/iter/adapters/filter.rs b/library/core/src/iter/adapters/filter.rs index a0afaa326..723657b9e 100644 --- a/library/core/src/iter/adapters/filter.rs +++ b/library/core/src/iter/adapters/filter.rs @@ -1,6 +1,9 @@ use crate::fmt; use crate::iter::{adapters::SourceIter, FusedIterator, InPlaceIterable}; use crate::ops::Try; +use core::array; +use core::mem::{ManuallyDrop, MaybeUninit}; +use core::ops::ControlFlow; /// An iterator that filters the elements of `iter` with `predicate`. /// @@ -57,6 +60,58 @@ where } #[inline] + fn next_chunk<const N: usize>( + &mut self, + ) -> Result<[Self::Item; N], array::IntoIter<Self::Item, N>> { + let mut array: [MaybeUninit<Self::Item>; N] = MaybeUninit::uninit_array(); + + struct Guard<'a, T> { + array: &'a mut [MaybeUninit<T>], + initialized: usize, + } + + impl<T> Drop for Guard<'_, T> { + #[inline] + fn drop(&mut self) { + if const { crate::mem::needs_drop::<T>() } { + // SAFETY: self.initialized is always <= N, which also is the length of the array. + unsafe { + core::ptr::drop_in_place(MaybeUninit::slice_assume_init_mut( + self.array.get_unchecked_mut(..self.initialized), + )); + } + } + } + } + + let mut guard = Guard { array: &mut array, initialized: 0 }; + + let result = self.iter.try_for_each(|element| { + let idx = guard.initialized; + guard.initialized = idx + (self.predicate)(&element) as usize; + + // SAFETY: Loop conditions ensure the index is in bounds. + unsafe { guard.array.get_unchecked_mut(idx) }.write(element); + + if guard.initialized < N { ControlFlow::Continue(()) } else { ControlFlow::Break(()) } + }); + + let guard = ManuallyDrop::new(guard); + + match result { + ControlFlow::Break(()) => { + // SAFETY: The loop above is only explicitly broken when the array has been fully initialized + Ok(unsafe { MaybeUninit::array_assume_init(array) }) + } + ControlFlow::Continue(()) => { + let initialized = guard.initialized; + // SAFETY: The range is in bounds since the loop breaks when reaching N elements. + Err(unsafe { array::IntoIter::new_unchecked(array, 0..initialized) }) + } + } + } + + #[inline] fn size_hint(&self) -> (usize, Option<usize>) { let (_, upper) = self.iter.size_hint(); (0, upper) // can't know a lower bound, due to the predicate diff --git a/library/core/src/iter/adapters/filter_map.rs b/library/core/src/iter/adapters/filter_map.rs index 6bdf53f7f..693479977 100644 --- a/library/core/src/iter/adapters/filter_map.rs +++ b/library/core/src/iter/adapters/filter_map.rs @@ -1,6 +1,7 @@ -use crate::fmt; use crate::iter::{adapters::SourceIter, FusedIterator, InPlaceIterable}; +use crate::mem::{ManuallyDrop, MaybeUninit}; use crate::ops::{ControlFlow, Try}; +use crate::{array, fmt}; /// An iterator that uses `f` to both filter and map elements from `iter`. /// @@ -62,6 +63,65 @@ where } #[inline] + fn next_chunk<const N: usize>( + &mut self, + ) -> Result<[Self::Item; N], array::IntoIter<Self::Item, N>> { + let mut array: [MaybeUninit<Self::Item>; N] = MaybeUninit::uninit_array(); + + struct Guard<'a, T> { + array: &'a mut [MaybeUninit<T>], + initialized: usize, + } + + impl<T> Drop for Guard<'_, T> { + #[inline] + fn drop(&mut self) { + if const { crate::mem::needs_drop::<T>() } { + // SAFETY: self.initialized is always <= N, which also is the length of the array. + unsafe { + core::ptr::drop_in_place(MaybeUninit::slice_assume_init_mut( + self.array.get_unchecked_mut(..self.initialized), + )); + } + } + } + } + + let mut guard = Guard { array: &mut array, initialized: 0 }; + + let result = self.iter.try_for_each(|element| { + let idx = guard.initialized; + let val = (self.f)(element); + guard.initialized = idx + val.is_some() as usize; + + // SAFETY: Loop conditions ensure the index is in bounds. + + unsafe { + let opt_payload_at = core::intrinsics::option_payload_ptr(&val); + let dst = guard.array.as_mut_ptr().add(idx); + crate::ptr::copy_nonoverlapping(opt_payload_at.cast(), dst, 1); + crate::mem::forget(val); + }; + + if guard.initialized < N { ControlFlow::Continue(()) } else { ControlFlow::Break(()) } + }); + + let guard = ManuallyDrop::new(guard); + + match result { + ControlFlow::Break(()) => { + // SAFETY: The loop above is only explicitly broken when the array has been fully initialized + Ok(unsafe { MaybeUninit::array_assume_init(array) }) + } + ControlFlow::Continue(()) => { + let initialized = guard.initialized; + // SAFETY: The range is in bounds since the loop breaks when reaching N elements. + Err(unsafe { array::IntoIter::new_unchecked(array, 0..initialized) }) + } + } + } + + #[inline] fn size_hint(&self) -> (usize, Option<usize>) { let (_, upper) = self.iter.size_hint(); (0, upper) // can't know a lower bound, due to the predicate diff --git a/library/core/src/iter/adapters/flatten.rs b/library/core/src/iter/adapters/flatten.rs index 2fd8a5c1d..2568aaf34 100644 --- a/library/core/src/iter/adapters/flatten.rs +++ b/library/core/src/iter/adapters/flatten.rs @@ -136,26 +136,12 @@ where } #[unstable(feature = "trusted_len", issue = "37572")] -unsafe impl<T, I, F, const N: usize> TrustedLen for FlatMap<I, [T; N], F> +unsafe impl<I, U, F> TrustedLen for FlatMap<I, U, F> where - I: TrustedLen, - F: FnMut(I::Item) -> [T; N], -{ -} - -#[unstable(feature = "trusted_len", issue = "37572")] -unsafe impl<'a, T, I, F, const N: usize> TrustedLen for FlatMap<I, &'a [T; N], F> -where - I: TrustedLen, - F: FnMut(I::Item) -> &'a [T; N], -{ -} - -#[unstable(feature = "trusted_len", issue = "37572")] -unsafe impl<'a, T, I, F, const N: usize> TrustedLen for FlatMap<I, &'a mut [T; N], F> -where - I: TrustedLen, - F: FnMut(I::Item) -> &'a mut [T; N], + I: Iterator, + U: IntoIterator, + F: FnMut(I::Item) -> U, + FlattenCompat<Map<I, F>, <U as IntoIterator>::IntoIter>: TrustedLen, { } @@ -298,8 +284,8 @@ where #[unstable(feature = "trusted_len", issue = "37572")] unsafe impl<I> TrustedLen for Flatten<I> where - I: TrustedLen, - <I as Iterator>::Item: TrustedConstSize, + I: Iterator<Item: IntoIterator>, + FlattenCompat<I, <I::Item as IntoIterator>::IntoIter>: TrustedLen, { } @@ -324,6 +310,7 @@ where /// Real logic of both `Flatten` and `FlatMap` which simply delegate to /// this type. #[derive(Clone, Debug)] +#[unstable(feature = "trusted_len", issue = "37572")] struct FlattenCompat<I, U> { iter: Fuse<I>, frontiter: Option<U>, @@ -477,6 +464,7 @@ where } } +#[unstable(feature = "trusted_len", issue = "37572")] impl<I, U> Iterator for FlattenCompat<I, U> where I: Iterator<Item: IntoIterator<IntoIter = U, Item = U::Item>>, @@ -591,6 +579,7 @@ where } } +#[unstable(feature = "trusted_len", issue = "37572")] impl<I, U> DoubleEndedIterator for FlattenCompat<I, U> where I: DoubleEndedIterator<Item: IntoIterator<IntoIter = U, Item = U::Item>>, @@ -660,6 +649,30 @@ where } } +#[unstable(feature = "trusted_len", issue = "37572")] +unsafe impl<const N: usize, I, T> TrustedLen + for FlattenCompat<I, <[T; N] as IntoIterator>::IntoIter> +where + I: TrustedLen<Item = [T; N]>, +{ +} + +#[unstable(feature = "trusted_len", issue = "37572")] +unsafe impl<'a, const N: usize, I, T> TrustedLen + for FlattenCompat<I, <&'a [T; N] as IntoIterator>::IntoIter> +where + I: TrustedLen<Item = &'a [T; N]>, +{ +} + +#[unstable(feature = "trusted_len", issue = "37572")] +unsafe impl<'a, const N: usize, I, T> TrustedLen + for FlattenCompat<I, <&'a mut [T; N] as IntoIterator>::IntoIter> +where + I: TrustedLen<Item = &'a mut [T; N]>, +{ +} + trait ConstSizeIntoIterator: IntoIterator { // FIXME(#31844): convert to an associated const once specialization supports that fn size() -> Option<usize>; @@ -696,19 +709,6 @@ impl<T, const N: usize> ConstSizeIntoIterator for &mut [T; N] { } } -#[doc(hidden)] -#[unstable(feature = "std_internals", issue = "none")] -// FIXME(#20400): Instead of this helper trait there should be multiple impl TrustedLen for Flatten<> -// blocks with different bounds on Iterator::Item but the compiler erroneously considers them overlapping -pub unsafe trait TrustedConstSize: IntoIterator {} - -#[unstable(feature = "std_internals", issue = "none")] -unsafe impl<T, const N: usize> TrustedConstSize for [T; N] {} -#[unstable(feature = "std_internals", issue = "none")] -unsafe impl<T, const N: usize> TrustedConstSize for &'_ [T; N] {} -#[unstable(feature = "std_internals", issue = "none")] -unsafe impl<T, const N: usize> TrustedConstSize for &'_ mut [T; N] {} - #[inline] fn and_then_or_clear<T, U>(opt: &mut Option<T>, f: impl FnOnce(&mut T) -> Option<U>) -> Option<U> { let x = f(opt.as_mut()?); diff --git a/library/core/src/iter/range.rs b/library/core/src/iter/range.rs index 37db07429..0171d8981 100644 --- a/library/core/src/iter/range.rs +++ b/library/core/src/iter/range.rs @@ -732,12 +732,18 @@ impl<A: Step> Iterator for ops::Range<A> { } #[inline] - fn min(mut self) -> Option<A> { + fn min(mut self) -> Option<A> + where + A: Ord, + { self.next() } #[inline] - fn max(mut self) -> Option<A> { + fn max(mut self) -> Option<A> + where + A: Ord, + { self.next_back() } @@ -1158,12 +1164,18 @@ impl<A: Step> Iterator for ops::RangeInclusive<A> { } #[inline] - fn min(mut self) -> Option<A> { + fn min(mut self) -> Option<A> + where + A: Ord, + { self.next() } #[inline] - fn max(mut self) -> Option<A> { + fn max(mut self) -> Option<A> + where + A: Ord, + { self.next_back() } diff --git a/library/core/src/iter/sources/empty.rs b/library/core/src/iter/sources/empty.rs index 617dfd123..243df015f 100644 --- a/library/core/src/iter/sources/empty.rs +++ b/library/core/src/iter/sources/empty.rs @@ -81,8 +81,7 @@ impl<T> Clone for Empty<T> { // not #[derive] because that adds a Default bound on T, // which isn't necessary. #[stable(feature = "iter_empty", since = "1.2.0")] -#[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] -impl<T> const Default for Empty<T> { +impl<T> Default for Empty<T> { fn default() -> Empty<T> { Empty(marker::PhantomData) } diff --git a/library/core/src/iter/traits/collect.rs b/library/core/src/iter/traits/collect.rs index e099700e3..0675e5635 100644 --- a/library/core/src/iter/traits/collect.rs +++ b/library/core/src/iter/traits/collect.rs @@ -95,6 +95,16 @@ #[stable(feature = "rust1", since = "1.0.0")] #[rustc_on_unimplemented( on( + _Self = "&[{A}]", + message = "a slice of type `{Self}` cannot be built since we need to store the elements somewhere", + label = "try explicitly collecting into a `Vec<{A}>`", + ), + on( + all(A = "{integer}", any(_Self = "&[{integral}]",)), + message = "a slice of type `{Self}` cannot be built since we need to store the elements somewhere", + label = "try explicitly collecting into a `Vec<{A}>`", + ), + on( _Self = "[{A}]", message = "a slice of type `{Self}` cannot be built since `{Self}` has no definite size", label = "try explicitly collecting into a `Vec<{A}>`", @@ -228,7 +238,6 @@ pub trait FromIterator<A>: Sized { #[rustc_diagnostic_item = "IntoIterator"] #[rustc_skip_array_during_method_dispatch] #[stable(feature = "rust1", since = "1.0.0")] -#[const_trait] pub trait IntoIterator { /// The type of the elements being iterated over. #[stable(feature = "rust1", since = "1.0.0")] @@ -264,7 +273,7 @@ pub trait IntoIterator { #[rustc_const_unstable(feature = "const_intoiterator_identity", issue = "90603")] #[stable(feature = "rust1", since = "1.0.0")] -impl<I: Iterator> const IntoIterator for I { +impl<I: Iterator> IntoIterator for I { type Item = I::Item; type IntoIter = I; diff --git a/library/core/src/iter/traits/iterator.rs b/library/core/src/iter/traits/iterator.rs index 028776042..dabfce144 100644 --- a/library/core/src/iter/traits/iterator.rs +++ b/library/core/src/iter/traits/iterator.rs @@ -70,7 +70,6 @@ fn _assert_is_object_safe(_: &dyn Iterator<Item = ()>) {} #[doc(notable_trait)] #[rustc_diagnostic_item = "Iterator"] #[must_use = "iterators are lazy and do nothing unless consumed"] -#[const_trait] pub trait Iterator { /// The type of the elements being iterated over. #[rustc_diagnostic_item = "IteratorItem"] diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs index 04243544b..6c419eb16 100644 --- a/library/core/src/lib.rs +++ b/library/core/src/lib.rs @@ -107,16 +107,13 @@ #![feature(const_arguments_as_str)] #![feature(const_array_from_ref)] #![feature(const_array_into_iter_constructors)] +#![feature(const_assume)] #![feature(const_bigint_helper_methods)] #![feature(const_black_box)] #![feature(const_caller_location)] #![feature(const_cell_into_inner)] #![feature(const_char_from_u32_unchecked)] -#![feature(const_clone)] -#![feature(const_cmp)] -#![feature(const_convert)] #![feature(const_cstr_methods)] -#![feature(const_default_impls)] #![feature(const_discriminant)] #![feature(const_eval_select)] #![feature(const_exact_div)] @@ -131,14 +128,12 @@ #![feature(const_intrinsic_forget)] #![feature(const_ipv4)] #![feature(const_ipv6)] -#![feature(const_is_char_boundary)] #![feature(const_likely)] #![feature(const_maybe_uninit_as_mut_ptr)] #![feature(const_maybe_uninit_assume_init)] #![feature(const_maybe_uninit_uninit_array)] #![feature(const_nonnull_new)] -#![feature(const_num_from_num)] -#![feature(const_ops)] +#![feature(const_num_midpoint)] #![feature(const_option)] #![feature(const_option_ext)] #![feature(const_pin)] @@ -146,22 +141,20 @@ #![feature(const_pointer_is_aligned)] #![feature(const_ptr_as_ref)] #![feature(const_ptr_is_null)] -#![feature(const_ptr_read)] #![feature(const_ptr_sub_ptr)] #![feature(const_ptr_write)] #![feature(const_raw_ptr_comparison)] #![feature(const_replace)] -#![feature(const_result_drop)] #![feature(const_size_of_val)] #![feature(const_size_of_val_raw)] #![feature(const_slice_from_raw_parts_mut)] #![feature(const_slice_from_ref)] #![feature(const_slice_index)] +#![feature(const_slice_is_ascii)] #![feature(const_slice_ptr_len)] #![feature(const_slice_split_at_mut)] #![feature(const_str_from_utf8_unchecked_mut)] #![feature(const_swap)] -#![feature(const_trait_impl)] #![feature(const_transmute_copy)] #![feature(const_try)] #![feature(const_type_id)] @@ -171,6 +164,7 @@ #![feature(const_waker)] #![feature(core_panic)] #![feature(duration_consts_float)] +#![feature(internal_impls_macro)] #![feature(ip)] #![feature(is_ascii_octdigit)] #![feature(maybe_uninit_uninit_array)] @@ -207,9 +201,9 @@ #![feature(const_mut_refs)] #![feature(const_precise_live_drops)] #![feature(const_refs_to_cell)] +#![feature(const_trait_impl)] #![feature(decl_macro)] #![feature(deprecated_suggestion)] -#![feature(derive_const)] #![feature(doc_cfg)] #![feature(doc_cfg_hide)] #![feature(doc_notable_trait)] @@ -222,6 +216,7 @@ #![feature(intra_doc_pointers)] #![feature(intrinsics)] #![feature(lang_items)] +#![feature(let_chains)] #![feature(link_llvm_intrinsics)] #![feature(macro_metavar_expr)] #![feature(min_specialization)] @@ -385,6 +380,7 @@ pub mod alloc; // note: does not need to be public mod bool; +mod escape; mod tuple; mod unit; diff --git a/library/core/src/macros/mod.rs b/library/core/src/macros/mod.rs index 7c93c93b4..c4134dbcd 100644 --- a/library/core/src/macros/mod.rs +++ b/library/core/src/macros/mod.rs @@ -498,7 +498,6 @@ macro_rules! r#try { /// In a `no_std` setup you are responsible for the implementation details of the components. /// /// ```no_run -/// # extern crate core; /// use core::fmt::Write; /// /// struct Example; @@ -1428,7 +1427,7 @@ pub(crate) mod builtin { #[rustc_builtin_macro] #[macro_export] #[rustc_diagnostic_item = "assert_macro"] - #[allow_internal_unstable(core_panic, edition_panic)] + #[allow_internal_unstable(core_panic, edition_panic, generic_assert_internals)] macro_rules! assert { ($cond:expr $(,)?) => {{ /* compiler built-in */ }}; ($cond:expr, $($arg:tt)+) => {{ /* compiler built-in */ }}; diff --git a/library/core/src/macros/panic.md b/library/core/src/macros/panic.md index 98fb7e9e4..8b549e187 100644 --- a/library/core/src/macros/panic.md +++ b/library/core/src/macros/panic.md @@ -42,7 +42,7 @@ the successful result of some computation, `Ok(T)`, or error types that represent an anticipated runtime failure mode of that computation, `Err(E)`. `Result` is used alongside user defined types which represent the various anticipated runtime failure modes that the associated computation could -encounter. `Result` must be propagated manually, often with the the help of the +encounter. `Result` must be propagated manually, often with the help of the `?` operator and `Try` trait, and they must be reported manually, often with the help of the `Error` trait. diff --git a/library/core/src/marker.rs b/library/core/src/marker.rs index 3cd4f5104..8dab8d1a6 100644 --- a/library/core/src/marker.rs +++ b/library/core/src/marker.rs @@ -12,6 +12,50 @@ use crate::fmt::Debug; use crate::hash::Hash; use crate::hash::Hasher; +/// Implements a given marker trait for multiple types at the same time. +/// +/// The basic syntax looks like this: +/// ```ignore private macro +/// marker_impls! { MarkerTrait for u8, i8 } +/// ``` +/// You can also implement `unsafe` traits +/// ```ignore private macro +/// marker_impls! { unsafe MarkerTrait for u8, i8 } +/// ``` +/// Add attributes to all impls: +/// ```ignore private macro +/// marker_impls! { +/// #[allow(lint)] +/// #[unstable(feature = "marker_trait", issue = "none")] +/// MarkerTrait for u8, i8 +/// } +/// ``` +/// And use generics: +/// ```ignore private macro +/// marker_impls! { +/// MarkerTrait for +/// u8, i8, +/// {T: ?Sized} *const T, +/// {T: ?Sized} *mut T, +/// {T: MarkerTrait} PhantomData<T>, +/// u32, +/// } +/// ``` +#[unstable(feature = "internal_impls_macro", issue = "none")] +macro marker_impls { + ( $(#[$($meta:tt)*])* $Trait:ident for $({$($bounds:tt)*})? $T:ty $(, $($rest:tt)*)? ) => { + $(#[$($meta)*])* impl< $($($bounds)*)? > $Trait for $T {} + marker_impls! { $(#[$($meta)*])* $Trait for $($($rest)*)? } + }, + ( $(#[$($meta:tt)*])* $Trait:ident for ) => {}, + + ( $(#[$($meta:tt)*])* unsafe $Trait:ident for $({$($bounds:tt)*})? $T:ty $(, $($rest:tt)*)? ) => { + $(#[$($meta)*])* unsafe impl< $($($bounds)*)? > $Trait for $T {} + marker_impls! { $(#[$($meta)*])* unsafe $Trait for $($($rest)*)? } + }, + ( $(#[$($meta:tt)*])* unsafe $Trait:ident for ) => {}, +} + /// Types that can be transferred across thread boundaries. /// /// This trait is automatically implemented when the compiler determines it's @@ -24,7 +68,7 @@ use crate::hash::Hasher; /// operations. Its cousin [`sync::Arc`][arc] does use atomic operations (incurring /// some overhead) and thus is `Send`. /// -/// See [the Nomicon](../../nomicon/send-and-sync.html) for more details. +/// See [the Nomicon](../../nomicon/send-and-sync.html) and the [`Sync`] trait for more details. /// /// [`Rc`]: ../../std/rc/struct.Rc.html /// [arc]: ../../std/sync/struct.Arc.html @@ -214,6 +258,20 @@ pub trait StructuralEq { // Empty. } +// FIXME: Remove special cases of these types from the compiler pattern checking code and always check `T: StructuralEq` instead +marker_impls! { + #[unstable(feature = "structural_match", issue = "31434")] + StructuralEq for + usize, u8, u16, u32, u64, u128, + isize, i8, i16, i32, i64, i128, + bool, + char, + str /* Technically requires `[u8]: StructuralEq` */, + {T, const N: usize} [T; N], + {T} [T], + {T: ?Sized} &T, +} + /// Types whose values can be duplicated simply by copying bits. /// /// By default, variable bindings have 'move semantics.' In other @@ -401,6 +459,30 @@ pub macro Copy($item:item) { /* compiler built-in */ } +// Implementations of `Copy` for primitive types. +// +// Implementations that cannot be described in Rust +// are implemented in `traits::SelectionContext::copy_clone_conditions()` +// in `rustc_trait_selection`. +marker_impls! { + #[stable(feature = "rust1", since = "1.0.0")] + Copy for + usize, u8, u16, u32, u64, u128, + isize, i8, i16, i32, i64, i128, + f32, f64, + bool, char, + {T: ?Sized} *const T, + {T: ?Sized} *mut T, + +} + +#[unstable(feature = "never_type", issue = "35121")] +impl Copy for ! {} + +/// Shared references can be copied, but mutable references *cannot*! +#[stable(feature = "rust1", since = "1.0.0")] +impl<T: ?Sized> Copy for &T {} + /// Types for which it is safe to share references between threads. /// /// This trait is automatically implemented when the compiler determines @@ -426,6 +508,11 @@ pub macro Copy($item:item) { /// becomes read-only, as if it were a `& &T`. Hence there is no risk /// of a data race. /// +/// A shorter overview of how [`Sync`] and [`Send`] relate to referencing: +/// * `&T` is [`Send`] if and only if `T` is [`Sync`] +/// * `&mut T` is [`Send`] if and only if `T` is [`Send`] +/// * `&T` and `&mut T` are [`Sync`] if and only if `T` is [`Sync`] +/// /// Types that are not `Sync` are those that have "interior /// mutability" in a non-thread-safe form, such as [`Cell`][cell] /// and [`RefCell`][refcell]. These types allow for mutation of @@ -591,14 +678,14 @@ impl<T: ?Sized> !Sync for *mut T {} /// use std::marker::PhantomData; /// /// # #[allow(dead_code)] -/// struct Slice<'a, T: 'a> { +/// struct Slice<'a, T> { /// start: *const T, /// end: *const T, /// phantom: PhantomData<&'a T>, /// } /// ``` /// -/// This also in turn requires the annotation `T: 'a`, indicating +/// This also in turn infers the lifetime bound `T: 'a`, indicating /// that any references in `T` are valid over the lifetime `'a`. /// /// When initializing a `Slice` you simply provide the value @@ -607,7 +694,7 @@ impl<T: ?Sized> !Sync for *mut T {} /// ``` /// # #![allow(dead_code)] /// # use std::marker::PhantomData; -/// # struct Slice<'a, T: 'a> { +/// # struct Slice<'a, T> { /// # start: *const T, /// # end: *const T, /// # phantom: PhantomData<&'a T>, @@ -669,16 +756,11 @@ impl<T: ?Sized> !Sync for *mut T {} /// /// ## Ownership and the drop check /// -/// Adding a field of type `PhantomData<T>` indicates that your -/// type owns data of type `T`. This in turn implies that when your -/// type is dropped, it may drop one or more instances of the type -/// `T`. This has bearing on the Rust compiler's [drop check] -/// analysis. +/// The exact interaction of `PhantomData` with drop check **may change in the future**. /// -/// If your struct does not in fact *own* the data of type `T`, it is -/// better to use a reference type, like `PhantomData<&'a T>` -/// (ideally) or `PhantomData<*const T>` (if no lifetime applies), so -/// as not to indicate ownership. +/// Currently, adding a field of type `PhantomData<T>` indicates that your type *owns* data of type +/// `T` in very rare circumstances. This in turn has effects on the Rust compiler's [drop check] +/// analysis. For the exact rules, see the [drop check] documentation. /// /// ## Layout /// @@ -686,7 +768,7 @@ impl<T: ?Sized> !Sync for *mut T {} /// * `size_of::<PhantomData<T>>() == 0` /// * `align_of::<PhantomData<T>>() == 1` /// -/// [drop check]: ../../nomicon/dropck.html +/// [drop check]: Drop#drop-check #[lang = "phantom_data"] #[stable(feature = "rust1", since = "1.0.0")] pub struct PhantomData<T: ?Sized>; @@ -732,8 +814,7 @@ impl<T: ?Sized> Clone for PhantomData<T> { } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] -impl<T: ?Sized> const Default for PhantomData<T> { +impl<T: ?Sized> Default for PhantomData<T> { fn default() -> Self { Self } @@ -774,11 +855,14 @@ pub trait DiscriminantKind { pub(crate) unsafe auto trait Freeze {} impl<T: ?Sized> !Freeze for UnsafeCell<T> {} -unsafe impl<T: ?Sized> Freeze for PhantomData<T> {} -unsafe impl<T: ?Sized> Freeze for *const T {} -unsafe impl<T: ?Sized> Freeze for *mut T {} -unsafe impl<T: ?Sized> Freeze for &T {} -unsafe impl<T: ?Sized> Freeze for &mut T {} +marker_impls! { + unsafe Freeze for + {T: ?Sized} PhantomData<T>, + {T: ?Sized} *const T, + {T: ?Sized} *mut T, + {T: ?Sized} &T, + {T: ?Sized} &mut T, +} /// Types that can be safely moved after being pinned. /// @@ -839,17 +923,19 @@ pub struct PhantomPinned; #[stable(feature = "pin", since = "1.33.0")] impl !Unpin for PhantomPinned {} -#[stable(feature = "pin", since = "1.33.0")] -impl<'a, T: ?Sized + 'a> Unpin for &'a T {} - -#[stable(feature = "pin", since = "1.33.0")] -impl<'a, T: ?Sized + 'a> Unpin for &'a mut T {} - -#[stable(feature = "pin_raw", since = "1.38.0")] -impl<T: ?Sized> Unpin for *const T {} +marker_impls! { + #[stable(feature = "pin", since = "1.33.0")] + Unpin for + {T: ?Sized} &T, + {T: ?Sized} &mut T, +} -#[stable(feature = "pin_raw", since = "1.38.0")] -impl<T: ?Sized> Unpin for *mut T {} +marker_impls! { + #[stable(feature = "pin_raw", since = "1.38.0")] + Unpin for + {T: ?Sized} *const T, + {T: ?Sized} *mut T, +} /// A marker for types that can be dropped. /// @@ -858,8 +944,8 @@ impl<T: ?Sized> Unpin for *mut T {} #[unstable(feature = "const_trait_impl", issue = "67792")] #[lang = "destruct"] #[rustc_on_unimplemented(message = "can't drop `{Self}`", append_const_msg)] -#[const_trait] #[rustc_deny_explicit_impl] +#[const_trait] pub trait Destruct {} /// A marker for tuple types. @@ -884,43 +970,33 @@ pub trait Tuple {} )] pub trait PointerLike {} -/// Implementations of `Copy` for primitive types. -/// -/// Implementations that cannot be described in Rust -/// are implemented in `traits::SelectionContext::copy_clone_conditions()` -/// in `rustc_trait_selection`. -mod copy_impls { - - use super::Copy; - - macro_rules! impl_copy { - ($($t:ty)*) => { - $( - #[stable(feature = "rust1", since = "1.0.0")] - impl Copy for $t {} - )* - } - } - - impl_copy! { - usize u8 u16 u32 u64 u128 - isize i8 i16 i32 i64 i128 - f32 f64 - bool char - } - - #[unstable(feature = "never_type", issue = "35121")] - impl Copy for ! {} - - #[stable(feature = "rust1", since = "1.0.0")] - impl<T: ?Sized> Copy for *const T {} +/// A marker for types which can be used as types of `const` generic parameters. +#[cfg_attr(not(bootstrap), lang = "const_param_ty")] +#[unstable(feature = "adt_const_params", issue = "95174")] +#[rustc_on_unimplemented(message = "`{Self}` can't be used as a const parameter type")] +pub trait ConstParamTy: StructuralEq {} - #[stable(feature = "rust1", since = "1.0.0")] - impl<T: ?Sized> Copy for *mut T {} +/// Derive macro generating an impl of the trait `ConstParamTy`. +#[rustc_builtin_macro] +#[unstable(feature = "adt_const_params", issue = "95174")] +#[cfg(not(bootstrap))] +pub macro ConstParamTy($item:item) { + /* compiler built-in */ +} - /// Shared references can be copied, but mutable references *cannot*! - #[stable(feature = "rust1", since = "1.0.0")] - impl<T: ?Sized> Copy for &T {} +// FIXME(generic_const_parameter_types): handle `ty::FnDef`/`ty::Closure` +// FIXME(generic_const_parameter_types): handle `ty::Tuple` +marker_impls! { + #[unstable(feature = "adt_const_params", issue = "95174")] + ConstParamTy for + usize, u8, u16, u32, u64, u128, + isize, i8, i16, i32, i64, i128, + bool, + char, + str /* Technically requires `[u8]: ConstParamTy` */, + {T: ConstParamTy, const N: usize} [T; N], + {T: ConstParamTy} [T], + {T: ?Sized + ConstParamTy} &T, } /// A common trait implemented by all function pointers. @@ -930,7 +1006,6 @@ mod copy_impls { reason = "internal trait for implementing various traits for all function pointers" )] #[lang = "fn_ptr_trait"] -#[cfg(not(bootstrap))] #[rustc_deny_explicit_impl] pub trait FnPtr: Copy + Clone { /// Returns the address of the function pointer. diff --git a/library/core/src/mem/manually_drop.rs b/library/core/src/mem/manually_drop.rs index 3d719afe4..5f3d66e37 100644 --- a/library/core/src/mem/manually_drop.rs +++ b/library/core/src/mem/manually_drop.rs @@ -146,8 +146,7 @@ impl<T: ?Sized> ManuallyDrop<T> { } #[stable(feature = "manually_drop", since = "1.20.0")] -#[rustc_const_unstable(feature = "const_deref", issue = "88955")] -impl<T: ?Sized> const Deref for ManuallyDrop<T> { +impl<T: ?Sized> Deref for ManuallyDrop<T> { type Target = T; #[inline(always)] fn deref(&self) -> &T { @@ -156,8 +155,7 @@ impl<T: ?Sized> const Deref for ManuallyDrop<T> { } #[stable(feature = "manually_drop", since = "1.20.0")] -#[rustc_const_unstable(feature = "const_deref", issue = "88955")] -impl<T: ?Sized> const DerefMut for ManuallyDrop<T> { +impl<T: ?Sized> DerefMut for ManuallyDrop<T> { #[inline(always)] fn deref_mut(&mut self) -> &mut T { &mut self.value diff --git a/library/core/src/mem/maybe_uninit.rs b/library/core/src/mem/maybe_uninit.rs index 9c6d48675..d09a24b4b 100644 --- a/library/core/src/mem/maybe_uninit.rs +++ b/library/core/src/mem/maybe_uninit.rs @@ -945,14 +945,10 @@ impl<T> MaybeUninit<T> { // * `MaybeUninit<T>` and T are guaranteed to have the same layout // * `MaybeUninit` does not drop, so there are no double-frees // And thus the conversion is safe - let ret = unsafe { + unsafe { intrinsics::assert_inhabited::<[T; N]>(); - (&array as *const _ as *const [T; N]).read() - }; - - // FIXME: required to avoid `~const Destruct` bound - super::forget(array); - ret + intrinsics::transmute_unchecked(array) + } } /// Assuming all the elements are initialized, get a slice to them. @@ -1291,7 +1287,7 @@ impl<T, const N: usize> MaybeUninit<[T; N]> { #[inline] pub const fn transpose(self) -> [MaybeUninit<T>; N] { // SAFETY: T and MaybeUninit<T> have the same layout - unsafe { super::transmute_copy(&ManuallyDrop::new(self)) } + unsafe { intrinsics::transmute_unchecked(self) } } } @@ -1311,6 +1307,6 @@ impl<T, const N: usize> [MaybeUninit<T>; N] { #[inline] pub const fn transpose(self) -> MaybeUninit<[T; N]> { // SAFETY: T and MaybeUninit<T> have the same layout - unsafe { super::transmute_copy(&ManuallyDrop::new(self)) } + unsafe { intrinsics::transmute_unchecked(self) } } } diff --git a/library/core/src/mem/mod.rs b/library/core/src/mem/mod.rs index a67df7ed5..afbfd6d36 100644 --- a/library/core/src/mem/mod.rs +++ b/library/core/src/mem/mod.rs @@ -170,7 +170,7 @@ pub fn forget_unsized<T: ?Sized>(t: T) { /// /// The following table gives the size for primitives. /// -/// Type | size_of::\<Type>() +/// Type | `size_of::<Type>()` /// ---- | --------------- /// () | 0 /// bool | 1 @@ -190,8 +190,8 @@ pub fn forget_unsized<T: ?Sized>(t: T) { /// /// Furthermore, `usize` and `isize` have the same size. /// -/// The types `*const T`, `&T`, `Box<T>`, `Option<&T>`, and `Option<Box<T>>` all have -/// the same size. If `T` is Sized, all of those types have the same size as `usize`. +/// The types [`*const T`], `&T`, [`Box<T>`], [`Option<&T>`], and `Option<Box<T>>` all have +/// the same size. If `T` is `Sized`, all of those types have the same size as `usize`. /// /// The mutability of a pointer does not change its size. As such, `&T` and `&mut T` /// have the same size. Likewise for `*const T` and `*mut T`. @@ -203,7 +203,7 @@ pub fn forget_unsized<T: ?Sized>(t: T) { /// /// ## Size of Structs /// -/// For `structs`, the size is determined by the following algorithm. +/// For `struct`s, the size is determined by the following algorithm. /// /// For each field in the struct ordered by declaration order: /// @@ -299,6 +299,10 @@ pub fn forget_unsized<T: ?Sized>(t: T) { /// ``` /// /// [alignment]: align_of +/// [`*const T`]: primitive@pointer +/// [`Box<T>`]: ../../std/boxed/struct.Box.html +/// [`Option<&T>`]: crate::option::Option +/// #[inline(always)] #[must_use] #[stable(feature = "rust1", since = "1.0.0")] @@ -311,7 +315,7 @@ pub const fn size_of<T>() -> usize { /// Returns the size of the pointed-to value in bytes. /// -/// This is usually the same as `size_of::<T>()`. However, when `T` *has* no +/// This is usually the same as [`size_of::<T>()`]. However, when `T` *has* no /// statically-known size, e.g., a slice [`[T]`][slice] or a [trait object], /// then `size_of_val` can be used to get the dynamically-known size. /// @@ -328,6 +332,8 @@ pub const fn size_of<T>() -> usize { /// let y: &[u8] = &x; /// assert_eq!(13, mem::size_of_val(y)); /// ``` +/// +/// [`size_of::<T>()`]: size_of #[inline] #[must_use] #[stable(feature = "rust1", since = "1.0.0")] @@ -340,7 +346,7 @@ pub const fn size_of_val<T: ?Sized>(val: &T) -> usize { /// Returns the size of the pointed-to value in bytes. /// -/// This is usually the same as `size_of::<T>()`. However, when `T` *has* no +/// This is usually the same as [`size_of::<T>()`]. However, when `T` *has* no /// statically-known size, e.g., a slice [`[T]`][slice] or a [trait object], /// then `size_of_val_raw` can be used to get the dynamically-known size. /// @@ -363,6 +369,7 @@ pub const fn size_of_val<T: ?Sized>(val: &T) -> usize { /// [`size_of_val`] on a reference to a type with an extern type tail. /// - otherwise, it is conservatively not allowed to call this function. /// +/// [`size_of::<T>()`]: size_of /// [trait object]: ../../book/ch17-02-trait-objects.html /// [extern type]: ../../unstable-book/language-features/extern-types.html /// @@ -961,6 +968,7 @@ pub const fn replace<T>(dest: &mut T, src: T) -> T { /// Integers and other types implementing [`Copy`] are unaffected by `drop`. /// /// ``` +/// # #![cfg_attr(not(bootstrap), allow(dropping_copy_types))] /// #[derive(Copy, Clone)] /// struct Foo(u8); /// @@ -1272,3 +1280,45 @@ pub trait SizedTypeProperties: Sized { #[doc(hidden)] #[unstable(feature = "sized_type_properties", issue = "none")] impl<T> SizedTypeProperties for T {} + +/// Expands to the offset in bytes of a field from the beginning of the given type. +/// +/// Only structs, unions and tuples are supported. +/// +/// Nested field accesses may be used, but not array indexes like in `C`'s `offsetof`. +/// +/// Note that the output of this macro is not stable, except for `#[repr(C)]` types. +/// +/// # Examples +/// +/// ``` +/// #![feature(offset_of)] +/// +/// use std::mem; +/// #[repr(C)] +/// struct FieldStruct { +/// first: u8, +/// second: u16, +/// third: u8 +/// } +/// +/// assert_eq!(mem::offset_of!(FieldStruct, first), 0); +/// assert_eq!(mem::offset_of!(FieldStruct, second), 2); +/// assert_eq!(mem::offset_of!(FieldStruct, third), 4); +/// +/// #[repr(C)] +/// struct NestedA { +/// b: NestedB +/// } +/// +/// #[repr(C)] +/// struct NestedB(u8); +/// +/// assert_eq!(mem::offset_of!(NestedA, b.0), 0); +/// ``` +#[cfg(not(bootstrap))] +#[unstable(feature = "offset_of", issue = "106655")] +#[allow_internal_unstable(builtin_syntax)] +pub macro offset_of($Container:ty, $($fields:tt).+ $(,)?) { + builtin # offset_of($Container, $($fields).+) +} diff --git a/library/core/src/mem/transmutability.rs b/library/core/src/mem/transmutability.rs index b53a330fa..87ae30619 100644 --- a/library/core/src/mem/transmutability.rs +++ b/library/core/src/mem/transmutability.rs @@ -81,8 +81,7 @@ impl Assume { // FIXME(jswrenn): This const op is not actually usable. Why? // https://github.com/rust-lang/rust/pull/100726#issuecomment-1219928926 #[unstable(feature = "transmutability", issue = "99571")] -#[rustc_const_unstable(feature = "transmutability", issue = "99571")] -impl const core::ops::Add for Assume { +impl core::ops::Add for Assume { type Output = Assume; fn add(self, other_assumptions: Assume) -> Assume { @@ -93,8 +92,7 @@ impl const core::ops::Add for Assume { // FIXME(jswrenn): This const op is not actually usable. Why? // https://github.com/rust-lang/rust/pull/100726#issuecomment-1219928926 #[unstable(feature = "transmutability", issue = "99571")] -#[rustc_const_unstable(feature = "transmutability", issue = "99571")] -impl const core::ops::Sub for Assume { +impl core::ops::Sub for Assume { type Output = Assume; fn sub(self, other_assumptions: Assume) -> Assume { diff --git a/library/core/src/net/socket_addr.rs b/library/core/src/net/socket_addr.rs index 2d48e2715..8396aecf9 100644 --- a/library/core/src/net/socket_addr.rs +++ b/library/core/src/net/socket_addr.rs @@ -122,6 +122,7 @@ impl SocketAddr { #[stable(feature = "ip_addr", since = "1.7.0")] #[must_use] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn new(ip: IpAddr, port: u16) -> SocketAddr { match ip { IpAddr::V4(a) => SocketAddr::V4(SocketAddrV4::new(a, port)), @@ -142,6 +143,7 @@ impl SocketAddr { #[must_use] #[stable(feature = "ip_addr", since = "1.7.0")] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn ip(&self) -> IpAddr { match *self { SocketAddr::V4(ref a) => IpAddr::V4(*a.ip()), @@ -161,6 +163,7 @@ impl SocketAddr { /// assert_eq!(socket.ip(), IpAddr::V4(Ipv4Addr::new(10, 10, 0, 1))); /// ``` #[stable(feature = "sockaddr_setters", since = "1.9.0")] + #[inline] pub fn set_ip(&mut self, new_ip: IpAddr) { // `match (*self, new_ip)` would have us mutate a copy of self only to throw it away. match (self, new_ip) { @@ -183,6 +186,7 @@ impl SocketAddr { #[must_use] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn port(&self) -> u16 { match *self { SocketAddr::V4(ref a) => a.port(), @@ -202,6 +206,7 @@ impl SocketAddr { /// assert_eq!(socket.port(), 1025); /// ``` #[stable(feature = "sockaddr_setters", since = "1.9.0")] + #[inline] pub fn set_port(&mut self, new_port: u16) { match *self { SocketAddr::V4(ref mut a) => a.set_port(new_port), @@ -227,6 +232,7 @@ impl SocketAddr { #[must_use] #[stable(feature = "sockaddr_checker", since = "1.16.0")] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn is_ipv4(&self) -> bool { matches!(*self, SocketAddr::V4(_)) } @@ -249,6 +255,7 @@ impl SocketAddr { #[must_use] #[stable(feature = "sockaddr_checker", since = "1.16.0")] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn is_ipv6(&self) -> bool { matches!(*self, SocketAddr::V6(_)) } @@ -269,6 +276,7 @@ impl SocketAddrV4 { #[stable(feature = "rust1", since = "1.0.0")] #[must_use] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn new(ip: Ipv4Addr, port: u16) -> SocketAddrV4 { SocketAddrV4 { ip, port } } @@ -286,6 +294,7 @@ impl SocketAddrV4 { #[must_use] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn ip(&self) -> &Ipv4Addr { &self.ip } @@ -302,6 +311,7 @@ impl SocketAddrV4 { /// assert_eq!(socket.ip(), &Ipv4Addr::new(192, 168, 0, 1)); /// ``` #[stable(feature = "sockaddr_setters", since = "1.9.0")] + #[inline] pub fn set_ip(&mut self, new_ip: Ipv4Addr) { self.ip = new_ip; } @@ -319,6 +329,7 @@ impl SocketAddrV4 { #[must_use] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn port(&self) -> u16 { self.port } @@ -335,6 +346,7 @@ impl SocketAddrV4 { /// assert_eq!(socket.port(), 4242); /// ``` #[stable(feature = "sockaddr_setters", since = "1.9.0")] + #[inline] pub fn set_port(&mut self, new_port: u16) { self.port = new_port; } @@ -360,6 +372,7 @@ impl SocketAddrV6 { #[stable(feature = "rust1", since = "1.0.0")] #[must_use] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn new(ip: Ipv6Addr, port: u16, flowinfo: u32, scope_id: u32) -> SocketAddrV6 { SocketAddrV6 { ip, port, flowinfo, scope_id } } @@ -377,6 +390,7 @@ impl SocketAddrV6 { #[must_use] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn ip(&self) -> &Ipv6Addr { &self.ip } @@ -393,6 +407,7 @@ impl SocketAddrV6 { /// assert_eq!(socket.ip(), &Ipv6Addr::new(76, 45, 0, 0, 0, 0, 0, 0)); /// ``` #[stable(feature = "sockaddr_setters", since = "1.9.0")] + #[inline] pub fn set_ip(&mut self, new_ip: Ipv6Addr) { self.ip = new_ip; } @@ -410,6 +425,7 @@ impl SocketAddrV6 { #[must_use] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn port(&self) -> u16 { self.port } @@ -426,6 +442,7 @@ impl SocketAddrV6 { /// assert_eq!(socket.port(), 4242); /// ``` #[stable(feature = "sockaddr_setters", since = "1.9.0")] + #[inline] pub fn set_port(&mut self, new_port: u16) { self.port = new_port; } @@ -453,6 +470,7 @@ impl SocketAddrV6 { #[must_use] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn flowinfo(&self) -> u32 { self.flowinfo } @@ -471,6 +489,7 @@ impl SocketAddrV6 { /// assert_eq!(socket.flowinfo(), 56); /// ``` #[stable(feature = "sockaddr_setters", since = "1.9.0")] + #[inline] pub fn set_flowinfo(&mut self, new_flowinfo: u32) { self.flowinfo = new_flowinfo; } @@ -493,6 +512,7 @@ impl SocketAddrV6 { #[must_use] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_const_stable(feature = "const_socketaddr", since = "1.69.0")] + #[inline] pub const fn scope_id(&self) -> u32 { self.scope_id } @@ -511,6 +531,7 @@ impl SocketAddrV6 { /// assert_eq!(socket.scope_id(), 42); /// ``` #[stable(feature = "sockaddr_setters", since = "1.9.0")] + #[inline] pub fn set_scope_id(&mut self, new_scope_id: u32) { self.scope_id = new_scope_id; } @@ -519,6 +540,7 @@ impl SocketAddrV6 { #[stable(feature = "ip_from_ip", since = "1.16.0")] impl From<SocketAddrV4> for SocketAddr { /// Converts a [`SocketAddrV4`] into a [`SocketAddr::V4`]. + #[inline] fn from(sock4: SocketAddrV4) -> SocketAddr { SocketAddr::V4(sock4) } @@ -527,6 +549,7 @@ impl From<SocketAddrV4> for SocketAddr { #[stable(feature = "ip_from_ip", since = "1.16.0")] impl From<SocketAddrV6> for SocketAddr { /// Converts a [`SocketAddrV6`] into a [`SocketAddr::V6`]. + #[inline] fn from(sock6: SocketAddrV6) -> SocketAddr { SocketAddr::V6(sock6) } @@ -624,6 +647,7 @@ impl fmt::Debug for SocketAddrV6 { #[stable(feature = "socketaddr_ordering", since = "1.45.0")] impl PartialOrd for SocketAddrV4 { + #[inline] fn partial_cmp(&self, other: &SocketAddrV4) -> Option<Ordering> { Some(self.cmp(other)) } @@ -631,6 +655,7 @@ impl PartialOrd for SocketAddrV4 { #[stable(feature = "socketaddr_ordering", since = "1.45.0")] impl PartialOrd for SocketAddrV6 { + #[inline] fn partial_cmp(&self, other: &SocketAddrV6) -> Option<Ordering> { Some(self.cmp(other)) } @@ -638,6 +663,7 @@ impl PartialOrd for SocketAddrV6 { #[stable(feature = "socketaddr_ordering", since = "1.45.0")] impl Ord for SocketAddrV4 { + #[inline] fn cmp(&self, other: &SocketAddrV4) -> Ordering { self.ip().cmp(other.ip()).then(self.port().cmp(&other.port())) } @@ -645,6 +671,7 @@ impl Ord for SocketAddrV4 { #[stable(feature = "socketaddr_ordering", since = "1.45.0")] impl Ord for SocketAddrV6 { + #[inline] fn cmp(&self, other: &SocketAddrV6) -> Ordering { self.ip().cmp(other.ip()).then(self.port().cmp(&other.port())) } diff --git a/library/core/src/num/error.rs b/library/core/src/num/error.rs index 1bae4efe7..14e99578a 100644 --- a/library/core/src/num/error.rs +++ b/library/core/src/num/error.rs @@ -26,15 +26,15 @@ impl Error for TryFromIntError { } #[stable(feature = "try_from", since = "1.34.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl const From<Infallible> for TryFromIntError { +impl From<Infallible> for TryFromIntError { fn from(x: Infallible) -> TryFromIntError { match x {} } } #[unstable(feature = "never_type", issue = "35121")] -impl const From<!> for TryFromIntError { +impl From<!> for TryFromIntError { + #[inline] fn from(never: !) -> TryFromIntError { // Match rather than coerce to make sure that code like // `From<Infallible> for TryFromIntError` above will keep working diff --git a/library/core/src/num/f32.rs b/library/core/src/num/f32.rs index 1c6819b54..4a035ad61 100644 --- a/library/core/src/num/f32.rs +++ b/library/core/src/num/f32.rs @@ -940,6 +940,42 @@ impl f32 { } } + /// Calculates the middle point of `self` and `rhs`. + /// + /// This returns NaN when *either* argument is NaN or if a combination of + /// +inf and -inf is provided as arguments. + /// + /// # Examples + /// + /// ``` + /// #![feature(num_midpoint)] + /// assert_eq!(1f32.midpoint(4.0), 2.5); + /// assert_eq!((-5.5f32).midpoint(8.0), 1.25); + /// ``` + #[unstable(feature = "num_midpoint", issue = "110840")] + pub fn midpoint(self, other: f32) -> f32 { + const LO: f32 = f32::MIN_POSITIVE * 2.; + const HI: f32 = f32::MAX / 2.; + + let (a, b) = (self, other); + let abs_a = a.abs_private(); + let abs_b = b.abs_private(); + + if abs_a <= HI && abs_b <= HI { + // Overflow is impossible + (a + b) / 2. + } else if abs_a < LO { + // Not safe to halve a + a + (b / 2.) + } else if abs_b < LO { + // Not safe to halve b + (a / 2.) + b + } else { + // Not safe to halve a and b + (a / 2.) + (b / 2.) + } + } + /// Rounds toward zero and converts to any primitive integer type, /// assuming that the value is finite and fits in that type. /// diff --git a/library/core/src/num/f64.rs b/library/core/src/num/f64.rs index 1e7387217..3aafc435f 100644 --- a/library/core/src/num/f64.rs +++ b/library/core/src/num/f64.rs @@ -951,6 +951,42 @@ impl f64 { } } + /// Calculates the middle point of `self` and `rhs`. + /// + /// This returns NaN when *either* argument is NaN or if a combination of + /// +inf and -inf is provided as arguments. + /// + /// # Examples + /// + /// ``` + /// #![feature(num_midpoint)] + /// assert_eq!(1f64.midpoint(4.0), 2.5); + /// assert_eq!((-5.5f64).midpoint(8.0), 1.25); + /// ``` + #[unstable(feature = "num_midpoint", issue = "110840")] + pub fn midpoint(self, other: f64) -> f64 { + const LO: f64 = f64::MIN_POSITIVE * 2.; + const HI: f64 = f64::MAX / 2.; + + let (a, b) = (self, other); + let abs_a = a.abs_private(); + let abs_b = b.abs_private(); + + if abs_a <= HI && abs_b <= HI { + // Overflow is impossible + (a + b) / 2. + } else if abs_a < LO { + // Not safe to halve a + a + (b / 2.) + } else if abs_b < LO { + // Not safe to halve b + (a / 2.) + b + } else { + // Not safe to halve a and b + (a / 2.) + (b / 2.) + } + } + /// Rounds toward zero and converts to any primitive integer type, /// assuming that the value is finite and fits in that type. /// diff --git a/library/core/src/num/flt2dec/strategy/grisu.rs b/library/core/src/num/flt2dec/strategy/grisu.rs index ed3e0edaf..b9f0d114c 100644 --- a/library/core/src/num/flt2dec/strategy/grisu.rs +++ b/library/core/src/num/flt2dec/strategy/grisu.rs @@ -487,6 +487,22 @@ pub fn format_exact_opt<'a>( let vint = (v.f >> e) as u32; let vfrac = v.f & ((1 << e) - 1); + let requested_digits = buf.len(); + + const POW10_UP_TO_9: [u32; 10] = + [1, 10, 100, 1000, 10_000, 100_000, 1_000_000, 10_000_000, 100_000_000, 1_000_000_000]; + + // We deviate from the original algorithm here and do some early checks to determine if we can satisfy requested_digits. + // If we determine that we can't, we exit early and avoid most of the heavy lifting that the algorithm otherwise does. + // + // When vfrac is zero, we can easily determine if vint can satisfy requested digits: + // If requested_digits >= 11, vint is not able to exhaust the count by itself since 10^(11 -1) > u32 max value >= vint. + // If vint < 10^(requested_digits - 1), vint cannot exhaust the count. + // Otherwise, vint might be able to exhaust the count and we need to execute the rest of the code. + if (vfrac == 0) && ((requested_digits >= 11) || (vint < POW10_UP_TO_9[requested_digits - 1])) { + return None; + } + // both old `v` and new `v` (scaled by `10^-k`) has an error of < 1 ulp (Theorem 5.1). // as we don't know the error is positive or negative, we use two approximations // spaced equally and have the maximal error of 2 ulps (same to the shortest case). diff --git a/library/core/src/num/int_macros.rs b/library/core/src/num/int_macros.rs index aec15212d..1199d09b5 100644 --- a/library/core/src/num/int_macros.rs +++ b/library/core/src/num/int_macros.rs @@ -785,7 +785,7 @@ macro_rules! int_impl { // SAFETY: the caller must uphold the safety contract for // `unchecked_shl`. // Any legal shift amount is losslessly representable in the self type. - unsafe { intrinsics::unchecked_shl(self, rhs.try_into().ok().unwrap_unchecked()) } + unsafe { intrinsics::unchecked_shl(self, conv_rhs_for_unchecked_shift!($SelfT, rhs)) } } /// Checked shift right. Computes `self >> rhs`, returning `None` if `rhs` is @@ -833,7 +833,7 @@ macro_rules! int_impl { // SAFETY: the caller must uphold the safety contract for // `unchecked_shr`. // Any legal shift amount is losslessly representable in the self type. - unsafe { intrinsics::unchecked_shr(self, rhs.try_into().ok().unwrap_unchecked()) } + unsafe { intrinsics::unchecked_shr(self, conv_rhs_for_unchecked_shift!($SelfT, rhs)) } } /// Checked absolute value. Computes `self.abs()`, returning `None` if @@ -2332,6 +2332,44 @@ macro_rules! int_impl { } } + /// Calculates the middle point of `self` and `rhs`. + /// + /// `midpoint(a, b)` is `(a + b) >> 1` as if it were performed in a + /// sufficiently-large signed integral type. This implies that the result is + /// always rounded towards negative infinity and that no overflow will ever occur. + /// + /// # Examples + /// + /// ``` + /// #![feature(num_midpoint)] + #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".midpoint(4), 2);")] + #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".midpoint(-1), -1);")] + #[doc = concat!("assert_eq!((-1", stringify!($SelfT), ").midpoint(0), -1);")] + /// ``` + #[unstable(feature = "num_midpoint", issue = "110840")] + #[rustc_const_unstable(feature = "const_num_midpoint", issue = "110840")] + #[rustc_allow_const_fn_unstable(const_num_midpoint)] + #[must_use = "this returns the result of the operation, \ + without modifying the original"] + #[inline] + pub const fn midpoint(self, rhs: Self) -> Self { + const U: $UnsignedT = <$SelfT>::MIN.unsigned_abs(); + + // Map an $SelfT to an $UnsignedT + // ex: i8 [-128; 127] to [0; 255] + const fn map(a: $SelfT) -> $UnsignedT { + (a as $UnsignedT) ^ U + } + + // Map an $UnsignedT to an $SelfT + // ex: u8 [0; 255] to [-128; 127] + const fn demap(a: $UnsignedT) -> $SelfT { + (a ^ U) as $SelfT + } + + demap(<$UnsignedT>::midpoint(map(self), map(rhs))) + } + /// Returns the logarithm of the number with respect to an arbitrary base, /// rounded down. /// @@ -2603,13 +2641,16 @@ macro_rules! int_impl { #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline(always)] - #[rustc_allow_const_fn_unstable(const_cmp)] pub const fn signum(self) -> Self { // Picking the right way to phrase this is complicated // (<https://graphics.stanford.edu/~seander/bithacks.html#CopyIntegerSign>) // so delegate it to `Ord` which is already producing -1/0/+1 // exactly like we need and can be the place to deal with the complexity. - self.cmp(&0) as _ + + // FIXME(const-hack): replace with cmp + if self < 0 { -1 } + else if self == 0 { 0 } + else { 1 } } /// Returns `true` if `self` is positive and `false` if the number is zero or diff --git a/library/core/src/num/mod.rs b/library/core/src/num/mod.rs index 9b812bbfc..c9baa09f4 100644 --- a/library/core/src/num/mod.rs +++ b/library/core/src/num/mod.rs @@ -95,6 +95,57 @@ depending on the target pointer size. }; } +macro_rules! midpoint_impl { + ($SelfT:ty, unsigned) => { + /// Calculates the middle point of `self` and `rhs`. + /// + /// `midpoint(a, b)` is `(a + b) >> 1` as if it were performed in a + /// sufficiently-large signed integral type. This implies that the result is + /// always rounded towards negative infinity and that no overflow will ever occur. + /// + /// # Examples + /// + /// ``` + /// #![feature(num_midpoint)] + #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".midpoint(4), 2);")] + #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".midpoint(4), 2);")] + /// ``` + #[unstable(feature = "num_midpoint", issue = "110840")] + #[rustc_const_unstable(feature = "const_num_midpoint", issue = "110840")] + #[must_use = "this returns the result of the operation, \ + without modifying the original"] + #[inline] + pub const fn midpoint(self, rhs: $SelfT) -> $SelfT { + // Use the well known branchless algorthim from Hacker's Delight to compute + // `(a + b) / 2` without overflowing: `((a ^ b) >> 1) + (a & b)`. + ((self ^ rhs) >> 1) + (self & rhs) + } + }; + ($SelfT:ty, $WideT:ty, unsigned) => { + /// Calculates the middle point of `self` and `rhs`. + /// + /// `midpoint(a, b)` is `(a + b) >> 1` as if it were performed in a + /// sufficiently-large signed integral type. This implies that the result is + /// always rounded towards negative infinity and that no overflow will ever occur. + /// + /// # Examples + /// + /// ``` + /// #![feature(num_midpoint)] + #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".midpoint(4), 2);")] + #[doc = concat!("assert_eq!(1", stringify!($SelfT), ".midpoint(4), 2);")] + /// ``` + #[unstable(feature = "num_midpoint", issue = "110840")] + #[rustc_const_unstable(feature = "const_num_midpoint", issue = "110840")] + #[must_use = "this returns the result of the operation, \ + without modifying the original"] + #[inline] + pub const fn midpoint(self, rhs: $SelfT) -> $SelfT { + ((self as $WideT + rhs as $WideT) / 2) as $SelfT + } + }; +} + macro_rules! widening_impl { ($SelfT:ty, $WideT:ty, $BITS:literal, unsigned) => { /// Calculates the complete product `self * rhs` without the possibility to overflow. @@ -225,6 +276,23 @@ macro_rules! widening_impl { }; } +macro_rules! conv_rhs_for_unchecked_shift { + ($SelfT:ty, $x:expr) => {{ + #[inline] + fn conv(x: u32) -> $SelfT { + // FIXME(const-hack) replace with `.try_into().ok().unwrap_unchecked()`. + // SAFETY: Any legal shift amount must be losslessly representable in the self type. + unsafe { x.try_into().ok().unwrap_unchecked() } + } + #[inline] + const fn const_conv(x: u32) -> $SelfT { + x as _ + } + + intrinsics::const_eval_select(($x,), const_conv, conv) + }}; +} + impl i8 { int_impl! { Self = i8, @@ -438,6 +506,7 @@ impl u8 { bound_condition = "", } widening_impl! { u8, u16, 8, unsigned } + midpoint_impl! { u8, u16, unsigned } /// Checks if the value is within the ASCII range. /// @@ -455,7 +524,16 @@ impl u8 { #[rustc_const_stable(feature = "const_u8_is_ascii", since = "1.43.0")] #[inline] pub const fn is_ascii(&self) -> bool { - *self & 128 == 0 + *self <= 127 + } + + /// If the value of this byte is within the ASCII range, returns it as an + /// [ASCII character](ascii::Char). Otherwise, returns `None`. + #[must_use] + #[unstable(feature = "ascii_char", issue = "110998")] + #[inline] + pub const fn as_ascii(&self) -> Option<ascii::Char> { + ascii::Char::from_u8(*self) } /// Makes a copy of the value in its ASCII upper case equivalent. @@ -1040,6 +1118,7 @@ impl u16 { bound_condition = "", } widening_impl! { u16, u32, 16, unsigned } + midpoint_impl! { u16, u32, unsigned } /// Checks if the value is a Unicode surrogate code point, which are disallowed values for [`char`]. /// @@ -1088,6 +1167,7 @@ impl u32 { bound_condition = "", } widening_impl! { u32, u64, 32, unsigned } + midpoint_impl! { u32, u64, unsigned } } impl u64 { @@ -1111,6 +1191,7 @@ impl u64 { bound_condition = "", } widening_impl! { u64, u128, 64, unsigned } + midpoint_impl! { u64, u128, unsigned } } impl u128 { @@ -1135,6 +1216,7 @@ impl u128 { from_xe_bytes_doc = "", bound_condition = "", } + midpoint_impl! { u128, unsigned } } #[cfg(target_pointer_width = "16")] @@ -1159,6 +1241,7 @@ impl usize { bound_condition = " on 16-bit targets", } widening_impl! { usize, u32, 16, unsigned } + midpoint_impl! { usize, u32, unsigned } } #[cfg(target_pointer_width = "32")] @@ -1183,6 +1266,7 @@ impl usize { bound_condition = " on 32-bit targets", } widening_impl! { usize, u64, 32, unsigned } + midpoint_impl! { usize, u64, unsigned } } #[cfg(target_pointer_width = "64")] @@ -1207,6 +1291,7 @@ impl usize { bound_condition = " on 64-bit targets", } widening_impl! { usize, u128, 64, unsigned } + midpoint_impl! { usize, u128, unsigned } } impl usize { diff --git a/library/core/src/num/nonzero.rs b/library/core/src/num/nonzero.rs index 49d23abee..7f06e170a 100644 --- a/library/core/src/num/nonzero.rs +++ b/library/core/src/num/nonzero.rs @@ -1,7 +1,7 @@ //! Definitions of integer that is known not to equal zero. use crate::fmt; -use crate::ops::{BitOr, BitOrAssign, Div, Rem}; +use crate::ops::{BitOr, BitOrAssign, Div, Neg, Rem}; use crate::str::FromStr; use super::from_str_radix; @@ -96,8 +96,7 @@ macro_rules! nonzero_integers { } #[stable(feature = "from_nonzero", since = "1.31.0")] - #[rustc_const_unstable(feature = "const_num_from_num", issue = "87852")] - impl const From<$Ty> for $Int { + impl From<$Ty> for $Int { #[doc = concat!("Converts a `", stringify!($Ty), "` into an `", stringify!($Int), "`")] #[inline] fn from(nonzero: $Ty) -> Self { @@ -106,8 +105,7 @@ macro_rules! nonzero_integers { } #[stable(feature = "nonzero_bitor", since = "1.45.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitOr for $Ty { + impl BitOr for $Ty { type Output = Self; #[inline] fn bitor(self, rhs: Self) -> Self::Output { @@ -118,8 +116,7 @@ macro_rules! nonzero_integers { } #[stable(feature = "nonzero_bitor", since = "1.45.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitOr<$Int> for $Ty { + impl BitOr<$Int> for $Ty { type Output = Self; #[inline] fn bitor(self, rhs: $Int) -> Self::Output { @@ -131,8 +128,7 @@ macro_rules! nonzero_integers { } #[stable(feature = "nonzero_bitor", since = "1.45.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitOr<$Ty> for $Int { + impl BitOr<$Ty> for $Int { type Output = $Ty; #[inline] fn bitor(self, rhs: $Ty) -> Self::Output { @@ -144,8 +140,7 @@ macro_rules! nonzero_integers { } #[stable(feature = "nonzero_bitor", since = "1.45.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitOrAssign for $Ty { + impl BitOrAssign for $Ty { #[inline] fn bitor_assign(&mut self, rhs: Self) { *self = *self | rhs; @@ -153,8 +148,7 @@ macro_rules! nonzero_integers { } #[stable(feature = "nonzero_bitor", since = "1.45.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitOrAssign<$Int> for $Ty { + impl BitOrAssign<$Int> for $Ty { #[inline] fn bitor_assign(&mut self, rhs: $Int) { *self = *self | rhs; @@ -276,8 +270,7 @@ macro_rules! nonzero_integers_div { ( $( $Ty: ident($Int: ty); )+ ) => { $( #[stable(feature = "nonzero_div", since = "1.51.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Div<$Ty> for $Int { + impl Div<$Ty> for $Int { type Output = $Int; /// This operation rounds towards zero, /// truncating any fractional part of the exact result, and cannot panic. @@ -290,8 +283,7 @@ macro_rules! nonzero_integers_div { } #[stable(feature = "nonzero_div", since = "1.51.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Rem<$Ty> for $Int { + impl Rem<$Ty> for $Int { type Output = $Int; /// This operation satisfies `n % d == n - (n / d) * d`, and cannot panic. #[inline] @@ -501,6 +493,43 @@ macro_rules! nonzero_unsigned_operations { pub const fn ilog10(self) -> u32 { super::int_log10::$Int(self.0) } + + /// Calculates the middle point of `self` and `rhs`. + /// + /// `midpoint(a, b)` is `(a + b) >> 1` as if it were performed in a + /// sufficiently-large signed integral type. This implies that the result is + /// always rounded towards negative infinity and that no overflow will ever occur. + /// + /// # Examples + /// + /// ``` + /// #![feature(num_midpoint)] + #[doc = concat!("# use std::num::", stringify!($Ty), ";")] + /// + /// # fn main() { test().unwrap(); } + /// # fn test() -> Option<()> { + #[doc = concat!("let one = ", stringify!($Ty), "::new(1)?;")] + #[doc = concat!("let two = ", stringify!($Ty), "::new(2)?;")] + #[doc = concat!("let four = ", stringify!($Ty), "::new(4)?;")] + /// + /// assert_eq!(one.midpoint(four), two); + /// assert_eq!(four.midpoint(one), two); + /// # Some(()) + /// # } + /// ``` + #[unstable(feature = "num_midpoint", issue = "110840")] + #[rustc_const_unstable(feature = "const_num_midpoint", issue = "110840")] + #[rustc_allow_const_fn_unstable(const_num_midpoint)] + #[must_use = "this returns the result of the operation, \ + without modifying the original"] + #[inline] + pub const fn midpoint(self, rhs: Self) -> Self { + // SAFETY: The only way to get `0` with midpoint is to have two opposite or + // near opposite numbers: (-5, 5), (0, 1), (0, 0) which is impossible because + // of the unsignedness of this number and also because $Ty is guaranteed to + // never being 0. + unsafe { $Ty::new_unchecked(self.get().midpoint(rhs.get())) } + } } )+ } @@ -672,8 +701,7 @@ macro_rules! nonzero_signed_operations { /// assert_eq!(pos, pos.wrapping_abs()); /// assert_eq!(pos, neg.wrapping_abs()); /// assert_eq!(min, min.wrapping_abs()); - /// # // FIXME: add once Neg is implemented? - /// # // assert_eq!(max, (-max).wrapping_abs()); + /// assert_eq!(max, (-max).wrapping_abs()); /// # Some(()) /// # } /// ``` @@ -722,14 +750,37 @@ macro_rules! nonzero_signed_operations { unsafe { $Uty::new_unchecked(self.get().unsigned_abs()) } } + /// Returns `true` if `self` is positive and `false` if the + /// number is negative. + /// + /// # Example + /// + /// ``` + #[doc = concat!("# use std::num::", stringify!($Ty), ";")] + /// # fn main() { test().unwrap(); } + /// # fn test() -> Option<()> { + #[doc = concat!("let pos_five = ", stringify!($Ty), "::new(5)?;")] + #[doc = concat!("let neg_five = ", stringify!($Ty), "::new(-5)?;")] + /// + /// assert!(pos_five.is_positive()); + /// assert!(!neg_five.is_positive()); + /// # Some(()) + /// # } + /// ``` + #[must_use] + #[inline] + #[stable(feature = "nonzero_negation_ops", since = "1.71.0")] + #[rustc_const_stable(feature = "nonzero_negation_ops", since = "1.71.0")] + pub const fn is_positive(self) -> bool { + self.get().is_positive() + } + /// Returns `true` if `self` is negative and `false` if the /// number is positive. /// /// # Example /// /// ``` - /// #![feature(nonzero_negation_ops)] - /// #[doc = concat!("# use std::num::", stringify!($Ty), ";")] /// # fn main() { test().unwrap(); } /// # fn test() -> Option<()> { @@ -743,7 +794,8 @@ macro_rules! nonzero_signed_operations { /// ``` #[must_use] #[inline] - #[unstable(feature = "nonzero_negation_ops", issue = "102443")] + #[stable(feature = "nonzero_negation_ops", since = "1.71.0")] + #[rustc_const_stable(feature = "nonzero_negation_ops", since = "1.71.0")] pub const fn is_negative(self) -> bool { self.get().is_negative() } @@ -753,8 +805,6 @@ macro_rules! nonzero_signed_operations { /// # Example /// /// ``` - /// #![feature(nonzero_negation_ops)] - /// #[doc = concat!("# use std::num::", stringify!($Ty), ";")] /// # fn main() { test().unwrap(); } /// # fn test() -> Option<()> { @@ -769,7 +819,8 @@ macro_rules! nonzero_signed_operations { /// # } /// ``` #[inline] - #[unstable(feature = "nonzero_negation_ops", issue = "102443")] + #[stable(feature = "nonzero_negation_ops", since = "1.71.0")] + #[rustc_const_stable(feature = "nonzero_negation_ops", since = "1.71.0")] pub const fn checked_neg(self) -> Option<$Ty> { if let Some(result) = self.get().checked_neg() { // SAFETY: negation of nonzero cannot yield zero values. @@ -786,8 +837,6 @@ macro_rules! nonzero_signed_operations { /// # Example /// /// ``` - /// #![feature(nonzero_negation_ops)] - /// #[doc = concat!("# use std::num::", stringify!($Ty), ";")] /// # fn main() { test().unwrap(); } /// # fn test() -> Option<()> { @@ -802,7 +851,8 @@ macro_rules! nonzero_signed_operations { /// # } /// ``` #[inline] - #[unstable(feature = "nonzero_negation_ops", issue = "102443")] + #[stable(feature = "nonzero_negation_ops", since = "1.71.0")] + #[rustc_const_stable(feature = "nonzero_negation_ops", since = "1.71.0")] pub const fn overflowing_neg(self) -> ($Ty, bool) { let (result, overflow) = self.get().overflowing_neg(); // SAFETY: negation of nonzero cannot yield zero values. @@ -815,8 +865,6 @@ macro_rules! nonzero_signed_operations { /// # Example /// /// ``` - /// #![feature(nonzero_negation_ops)] - /// #[doc = concat!("# use std::num::", stringify!($Ty), ";")] /// # fn main() { test().unwrap(); } /// # fn test() -> Option<()> { @@ -836,7 +884,8 @@ macro_rules! nonzero_signed_operations { /// # } /// ``` #[inline] - #[unstable(feature = "nonzero_negation_ops", issue = "102443")] + #[stable(feature = "nonzero_negation_ops", since = "1.71.0")] + #[rustc_const_stable(feature = "nonzero_negation_ops", since = "1.71.0")] pub const fn saturating_neg(self) -> $Ty { if let Some(result) = self.checked_neg() { return result; @@ -853,8 +902,6 @@ macro_rules! nonzero_signed_operations { /// # Example /// /// ``` - /// #![feature(nonzero_negation_ops)] - /// #[doc = concat!("# use std::num::", stringify!($Ty), ";")] /// # fn main() { test().unwrap(); } /// # fn test() -> Option<()> { @@ -869,13 +916,28 @@ macro_rules! nonzero_signed_operations { /// # } /// ``` #[inline] - #[unstable(feature = "nonzero_negation_ops", issue = "102443")] + #[stable(feature = "nonzero_negation_ops", since = "1.71.0")] + #[rustc_const_stable(feature = "nonzero_negation_ops", since = "1.71.0")] pub const fn wrapping_neg(self) -> $Ty { let result = self.get().wrapping_neg(); // SAFETY: negation of nonzero cannot yield zero values. unsafe { $Ty::new_unchecked(result) } } } + + #[stable(feature = "signed_nonzero_neg", since = "1.71.0")] + impl Neg for $Ty { + type Output = $Ty; + + #[inline] + fn neg(self) -> $Ty { + // SAFETY: negation of nonzero cannot yield zero values. + unsafe { $Ty::new_unchecked(self.get().neg()) } + } + } + + forward_ref_unop! { impl Neg, neg for $Ty, + #[stable(feature = "signed_nonzero_neg", since = "1.71.0")] } )+ } } diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs index 114deeea3..6f6b6dbb8 100644 --- a/library/core/src/num/uint_macros.rs +++ b/library/core/src/num/uint_macros.rs @@ -939,7 +939,7 @@ macro_rules! uint_impl { // SAFETY: the caller must uphold the safety contract for // `unchecked_shl`. // Any legal shift amount is losslessly representable in the self type. - unsafe { intrinsics::unchecked_shl(self, rhs.try_into().ok().unwrap_unchecked()) } + unsafe { intrinsics::unchecked_shl(self, conv_rhs_for_unchecked_shift!($SelfT, rhs)) } } /// Checked shift right. Computes `self >> rhs`, returning `None` @@ -987,7 +987,7 @@ macro_rules! uint_impl { // SAFETY: the caller must uphold the safety contract for // `unchecked_shr`. // Any legal shift amount is losslessly representable in the self type. - unsafe { intrinsics::unchecked_shr(self, rhs.try_into().ok().unwrap_unchecked()) } + unsafe { intrinsics::unchecked_shr(self, conv_rhs_for_unchecked_shift!($SelfT, rhs)) } } /// Checked exponentiation. Computes `self.pow(exp)`, returning `None` if diff --git a/library/core/src/num/wrapping.rs b/library/core/src/num/wrapping.rs index 5353d900e..ed354a2e5 100644 --- a/library/core/src/num/wrapping.rs +++ b/library/core/src/num/wrapping.rs @@ -87,8 +87,7 @@ impl<T: fmt::UpperHex> fmt::UpperHex for Wrapping<T> { macro_rules! sh_impl_signed { ($t:ident, $f:ident) => { #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Shl<$f> for Wrapping<$t> { + impl Shl<$f> for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -100,22 +99,20 @@ macro_rules! sh_impl_signed { } } } - forward_ref_binop! { impl const Shl, shl for Wrapping<$t>, $f, + forward_ref_binop! { impl Shl, shl for Wrapping<$t>, $f, #[stable(feature = "wrapping_ref_ops", since = "1.39.0")] } #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const ShlAssign<$f> for Wrapping<$t> { + impl ShlAssign<$f> for Wrapping<$t> { #[inline] fn shl_assign(&mut self, other: $f) { *self = *self << other; } } - forward_ref_op_assign! { impl const ShlAssign, shl_assign for Wrapping<$t>, $f } + forward_ref_op_assign! { impl ShlAssign, shl_assign for Wrapping<$t>, $f } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Shr<$f> for Wrapping<$t> { + impl Shr<$f> for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -127,26 +124,24 @@ macro_rules! sh_impl_signed { } } } - forward_ref_binop! { impl const Shr, shr for Wrapping<$t>, $f, + forward_ref_binop! { impl Shr, shr for Wrapping<$t>, $f, #[stable(feature = "wrapping_ref_ops", since = "1.39.0")] } #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const ShrAssign<$f> for Wrapping<$t> { + impl ShrAssign<$f> for Wrapping<$t> { #[inline] fn shr_assign(&mut self, other: $f) { *self = *self >> other; } } - forward_ref_op_assign! { impl const ShrAssign, shr_assign for Wrapping<$t>, $f } + forward_ref_op_assign! { impl ShrAssign, shr_assign for Wrapping<$t>, $f } }; } macro_rules! sh_impl_unsigned { ($t:ident, $f:ident) => { #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Shl<$f> for Wrapping<$t> { + impl Shl<$f> for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -154,22 +149,20 @@ macro_rules! sh_impl_unsigned { Wrapping(self.0.wrapping_shl((other & self::shift_max::$t as $f) as u32)) } } - forward_ref_binop! { impl const Shl, shl for Wrapping<$t>, $f, + forward_ref_binop! { impl Shl, shl for Wrapping<$t>, $f, #[stable(feature = "wrapping_ref_ops", since = "1.39.0")] } #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const ShlAssign<$f> for Wrapping<$t> { + impl ShlAssign<$f> for Wrapping<$t> { #[inline] fn shl_assign(&mut self, other: $f) { *self = *self << other; } } - forward_ref_op_assign! { impl const ShlAssign, shl_assign for Wrapping<$t>, $f } + forward_ref_op_assign! { impl ShlAssign, shl_assign for Wrapping<$t>, $f } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Shr<$f> for Wrapping<$t> { + impl Shr<$f> for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -177,18 +170,17 @@ macro_rules! sh_impl_unsigned { Wrapping(self.0.wrapping_shr((other & self::shift_max::$t as $f) as u32)) } } - forward_ref_binop! { impl const Shr, shr for Wrapping<$t>, $f, + forward_ref_binop! { impl Shr, shr for Wrapping<$t>, $f, #[stable(feature = "wrapping_ref_ops", since = "1.39.0")] } #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const ShrAssign<$f> for Wrapping<$t> { + impl ShrAssign<$f> for Wrapping<$t> { #[inline] fn shr_assign(&mut self, other: $f) { *self = *self >> other; } } - forward_ref_op_assign! { impl const ShrAssign, shr_assign for Wrapping<$t>, $f } + forward_ref_op_assign! { impl ShrAssign, shr_assign for Wrapping<$t>, $f } }; } @@ -217,8 +209,7 @@ sh_impl_all! { u8 u16 u32 u64 u128 usize i8 i16 i32 i64 i128 isize } macro_rules! wrapping_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Add for Wrapping<$t> { + impl Add for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -226,32 +217,29 @@ macro_rules! wrapping_impl { Wrapping(self.0.wrapping_add(other.0)) } } - forward_ref_binop! { impl const Add, add for Wrapping<$t>, Wrapping<$t>, + forward_ref_binop! { impl Add, add for Wrapping<$t>, Wrapping<$t>, #[stable(feature = "wrapping_ref", since = "1.14.0")] } #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const AddAssign for Wrapping<$t> { + impl AddAssign for Wrapping<$t> { #[inline] fn add_assign(&mut self, other: Wrapping<$t>) { *self = *self + other; } } - forward_ref_op_assign! { impl const AddAssign, add_assign for Wrapping<$t>, Wrapping<$t> } + forward_ref_op_assign! { impl AddAssign, add_assign for Wrapping<$t>, Wrapping<$t> } #[stable(feature = "wrapping_int_assign_impl", since = "1.60.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const AddAssign<$t> for Wrapping<$t> { + impl AddAssign<$t> for Wrapping<$t> { #[inline] fn add_assign(&mut self, other: $t) { *self = *self + Wrapping(other); } } - forward_ref_op_assign! { impl const AddAssign, add_assign for Wrapping<$t>, $t } + forward_ref_op_assign! { impl AddAssign, add_assign for Wrapping<$t>, $t } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Sub for Wrapping<$t> { + impl Sub for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -259,32 +247,29 @@ macro_rules! wrapping_impl { Wrapping(self.0.wrapping_sub(other.0)) } } - forward_ref_binop! { impl const Sub, sub for Wrapping<$t>, Wrapping<$t>, + forward_ref_binop! { impl Sub, sub for Wrapping<$t>, Wrapping<$t>, #[stable(feature = "wrapping_ref", since = "1.14.0")] } #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const SubAssign for Wrapping<$t> { + impl SubAssign for Wrapping<$t> { #[inline] fn sub_assign(&mut self, other: Wrapping<$t>) { *self = *self - other; } } - forward_ref_op_assign! { impl const SubAssign, sub_assign for Wrapping<$t>, Wrapping<$t> } + forward_ref_op_assign! { impl SubAssign, sub_assign for Wrapping<$t>, Wrapping<$t> } #[stable(feature = "wrapping_int_assign_impl", since = "1.60.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const SubAssign<$t> for Wrapping<$t> { + impl SubAssign<$t> for Wrapping<$t> { #[inline] fn sub_assign(&mut self, other: $t) { *self = *self - Wrapping(other); } } - forward_ref_op_assign! { impl const SubAssign, sub_assign for Wrapping<$t>, $t } + forward_ref_op_assign! { impl SubAssign, sub_assign for Wrapping<$t>, $t } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Mul for Wrapping<$t> { + impl Mul for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -296,28 +281,25 @@ macro_rules! wrapping_impl { #[stable(feature = "wrapping_ref", since = "1.14.0")] } #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const MulAssign for Wrapping<$t> { + impl MulAssign for Wrapping<$t> { #[inline] fn mul_assign(&mut self, other: Wrapping<$t>) { *self = *self * other; } } - forward_ref_op_assign! { impl const MulAssign, mul_assign for Wrapping<$t>, Wrapping<$t> } + forward_ref_op_assign! { impl MulAssign, mul_assign for Wrapping<$t>, Wrapping<$t> } #[stable(feature = "wrapping_int_assign_impl", since = "1.60.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const MulAssign<$t> for Wrapping<$t> { + impl MulAssign<$t> for Wrapping<$t> { #[inline] fn mul_assign(&mut self, other: $t) { *self = *self * Wrapping(other); } } - forward_ref_op_assign! { impl const MulAssign, mul_assign for Wrapping<$t>, $t } + forward_ref_op_assign! { impl MulAssign, mul_assign for Wrapping<$t>, $t } #[stable(feature = "wrapping_div", since = "1.3.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Div for Wrapping<$t> { + impl Div for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -325,32 +307,29 @@ macro_rules! wrapping_impl { Wrapping(self.0.wrapping_div(other.0)) } } - forward_ref_binop! { impl const Div, div for Wrapping<$t>, Wrapping<$t>, + forward_ref_binop! { impl Div, div for Wrapping<$t>, Wrapping<$t>, #[stable(feature = "wrapping_ref", since = "1.14.0")] } #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const DivAssign for Wrapping<$t> { + impl DivAssign for Wrapping<$t> { #[inline] fn div_assign(&mut self, other: Wrapping<$t>) { *self = *self / other; } } - forward_ref_op_assign! { impl const DivAssign, div_assign for Wrapping<$t>, Wrapping<$t> } + forward_ref_op_assign! { impl DivAssign, div_assign for Wrapping<$t>, Wrapping<$t> } #[stable(feature = "wrapping_int_assign_impl", since = "1.60.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const DivAssign<$t> for Wrapping<$t> { + impl DivAssign<$t> for Wrapping<$t> { #[inline] fn div_assign(&mut self, other: $t) { *self = *self / Wrapping(other); } } - forward_ref_op_assign! { impl const DivAssign, div_assign for Wrapping<$t>, $t } + forward_ref_op_assign! { impl DivAssign, div_assign for Wrapping<$t>, $t } #[stable(feature = "wrapping_impls", since = "1.7.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Rem for Wrapping<$t> { + impl Rem for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -358,32 +337,29 @@ macro_rules! wrapping_impl { Wrapping(self.0.wrapping_rem(other.0)) } } - forward_ref_binop! { impl const Rem, rem for Wrapping<$t>, Wrapping<$t>, + forward_ref_binop! { impl Rem, rem for Wrapping<$t>, Wrapping<$t>, #[stable(feature = "wrapping_ref", since = "1.14.0")] } #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const RemAssign for Wrapping<$t> { + impl RemAssign for Wrapping<$t> { #[inline] fn rem_assign(&mut self, other: Wrapping<$t>) { *self = *self % other; } } - forward_ref_op_assign! { impl const RemAssign, rem_assign for Wrapping<$t>, Wrapping<$t> } + forward_ref_op_assign! { impl RemAssign, rem_assign for Wrapping<$t>, Wrapping<$t> } #[stable(feature = "wrapping_int_assign_impl", since = "1.60.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const RemAssign<$t> for Wrapping<$t> { + impl RemAssign<$t> for Wrapping<$t> { #[inline] fn rem_assign(&mut self, other: $t) { *self = *self % Wrapping(other); } } - forward_ref_op_assign! { impl const RemAssign, rem_assign for Wrapping<$t>, $t } + forward_ref_op_assign! { impl RemAssign, rem_assign for Wrapping<$t>, $t } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Not for Wrapping<$t> { + impl Not for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -391,12 +367,11 @@ macro_rules! wrapping_impl { Wrapping(!self.0) } } - forward_ref_unop! { impl const Not, not for Wrapping<$t>, + forward_ref_unop! { impl Not, not for Wrapping<$t>, #[stable(feature = "wrapping_ref", since = "1.14.0")] } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitXor for Wrapping<$t> { + impl BitXor for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -404,32 +379,29 @@ macro_rules! wrapping_impl { Wrapping(self.0 ^ other.0) } } - forward_ref_binop! { impl const BitXor, bitxor for Wrapping<$t>, Wrapping<$t>, + forward_ref_binop! { impl BitXor, bitxor for Wrapping<$t>, Wrapping<$t>, #[stable(feature = "wrapping_ref", since = "1.14.0")] } #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitXorAssign for Wrapping<$t> { + impl BitXorAssign for Wrapping<$t> { #[inline] fn bitxor_assign(&mut self, other: Wrapping<$t>) { *self = *self ^ other; } } - forward_ref_op_assign! { impl const BitXorAssign, bitxor_assign for Wrapping<$t>, Wrapping<$t> } + forward_ref_op_assign! { impl BitXorAssign, bitxor_assign for Wrapping<$t>, Wrapping<$t> } #[stable(feature = "wrapping_int_assign_impl", since = "1.60.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitXorAssign<$t> for Wrapping<$t> { + impl BitXorAssign<$t> for Wrapping<$t> { #[inline] fn bitxor_assign(&mut self, other: $t) { *self = *self ^ Wrapping(other); } } - forward_ref_op_assign! { impl const BitXorAssign, bitxor_assign for Wrapping<$t>, $t } + forward_ref_op_assign! { impl BitXorAssign, bitxor_assign for Wrapping<$t>, $t } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitOr for Wrapping<$t> { + impl BitOr for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -437,32 +409,29 @@ macro_rules! wrapping_impl { Wrapping(self.0 | other.0) } } - forward_ref_binop! { impl const BitOr, bitor for Wrapping<$t>, Wrapping<$t>, + forward_ref_binop! { impl BitOr, bitor for Wrapping<$t>, Wrapping<$t>, #[stable(feature = "wrapping_ref", since = "1.14.0")] } #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitOrAssign for Wrapping<$t> { + impl BitOrAssign for Wrapping<$t> { #[inline] fn bitor_assign(&mut self, other: Wrapping<$t>) { *self = *self | other; } } - forward_ref_op_assign! { impl const BitOrAssign, bitor_assign for Wrapping<$t>, Wrapping<$t> } + forward_ref_op_assign! { impl BitOrAssign, bitor_assign for Wrapping<$t>, Wrapping<$t> } #[stable(feature = "wrapping_int_assign_impl", since = "1.60.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitOrAssign<$t> for Wrapping<$t> { + impl BitOrAssign<$t> for Wrapping<$t> { #[inline] fn bitor_assign(&mut self, other: $t) { *self = *self | Wrapping(other); } } - forward_ref_op_assign! { impl const BitOrAssign, bitor_assign for Wrapping<$t>, $t } + forward_ref_op_assign! { impl BitOrAssign, bitor_assign for Wrapping<$t>, $t } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitAnd for Wrapping<$t> { + impl BitAnd for Wrapping<$t> { type Output = Wrapping<$t>; #[inline] @@ -470,39 +439,36 @@ macro_rules! wrapping_impl { Wrapping(self.0 & other.0) } } - forward_ref_binop! { impl const BitAnd, bitand for Wrapping<$t>, Wrapping<$t>, + forward_ref_binop! { impl BitAnd, bitand for Wrapping<$t>, Wrapping<$t>, #[stable(feature = "wrapping_ref", since = "1.14.0")] } #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitAndAssign for Wrapping<$t> { + impl BitAndAssign for Wrapping<$t> { #[inline] fn bitand_assign(&mut self, other: Wrapping<$t>) { *self = *self & other; } } - forward_ref_op_assign! { impl const BitAndAssign, bitand_assign for Wrapping<$t>, Wrapping<$t> } + forward_ref_op_assign! { impl BitAndAssign, bitand_assign for Wrapping<$t>, Wrapping<$t> } #[stable(feature = "wrapping_int_assign_impl", since = "1.60.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitAndAssign<$t> for Wrapping<$t> { + impl BitAndAssign<$t> for Wrapping<$t> { #[inline] fn bitand_assign(&mut self, other: $t) { *self = *self & Wrapping(other); } } - forward_ref_op_assign! { impl const BitAndAssign, bitand_assign for Wrapping<$t>, $t } + forward_ref_op_assign! { impl BitAndAssign, bitand_assign for Wrapping<$t>, $t } #[stable(feature = "wrapping_neg", since = "1.10.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Neg for Wrapping<$t> { + impl Neg for Wrapping<$t> { type Output = Self; #[inline] fn neg(self) -> Self { Wrapping(0) - self } } - forward_ref_unop! { impl const Neg, neg for Wrapping<$t>, + forward_ref_unop! { impl Neg, neg for Wrapping<$t>, #[stable(feature = "wrapping_ref", since = "1.14.0")] } )*) diff --git a/library/core/src/ops/arith.rs b/library/core/src/ops/arith.rs index 0c7ee9630..840c8cd2f 100644 --- a/library/core/src/ops/arith.rs +++ b/library/core/src/ops/arith.rs @@ -73,7 +73,6 @@ append_const_msg )] #[doc(alias = "+")] -#[const_trait] pub trait Add<Rhs = Self> { /// The resulting type after applying the `+` operator. #[stable(feature = "rust1", since = "1.0.0")] @@ -95,8 +94,7 @@ pub trait Add<Rhs = Self> { macro_rules! add_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Add for $t { + impl Add for $t { type Output = $t; #[inline] @@ -104,7 +102,7 @@ macro_rules! add_impl { fn add(self, other: $t) -> $t { self + other } } - forward_ref_binop! { impl const Add, add for $t, $t } + forward_ref_binop! { impl Add, add for $t, $t } )*) } @@ -183,7 +181,6 @@ add_impl! { usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 f32 f64 } append_const_msg )] #[doc(alias = "-")] -#[const_trait] pub trait Sub<Rhs = Self> { /// The resulting type after applying the `-` operator. #[stable(feature = "rust1", since = "1.0.0")] @@ -205,8 +202,7 @@ pub trait Sub<Rhs = Self> { macro_rules! sub_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Sub for $t { + impl Sub for $t { type Output = $t; #[inline] @@ -214,7 +210,7 @@ macro_rules! sub_impl { fn sub(self, other: $t) -> $t { self - other } } - forward_ref_binop! { impl const Sub, sub for $t, $t } + forward_ref_binop! { impl Sub, sub for $t, $t } )*) } @@ -314,7 +310,6 @@ sub_impl! { usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 f32 f64 } label = "no implementation for `{Self} * {Rhs}`" )] #[doc(alias = "*")] -#[const_trait] pub trait Mul<Rhs = Self> { /// The resulting type after applying the `*` operator. #[stable(feature = "rust1", since = "1.0.0")] @@ -336,8 +331,7 @@ pub trait Mul<Rhs = Self> { macro_rules! mul_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Mul for $t { + impl Mul for $t { type Output = $t; #[inline] @@ -345,7 +339,7 @@ macro_rules! mul_impl { fn mul(self, other: $t) -> $t { self * other } } - forward_ref_binop! { impl const Mul, mul for $t, $t } + forward_ref_binop! { impl Mul, mul for $t, $t } )*) } @@ -449,7 +443,6 @@ mul_impl! { usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 f32 f64 } label = "no implementation for `{Self} / {Rhs}`" )] #[doc(alias = "/")] -#[const_trait] pub trait Div<Rhs = Self> { /// The resulting type after applying the `/` operator. #[stable(feature = "rust1", since = "1.0.0")] @@ -477,15 +470,14 @@ macro_rules! div_impl_integer { /// #[doc = $panic] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Div for $t { + impl Div for $t { type Output = $t; #[inline] fn div(self, other: $t) -> $t { self / other } } - forward_ref_binop! { impl const Div, div for $t, $t } + forward_ref_binop! { impl Div, div for $t, $t } )*)*) } @@ -497,15 +489,14 @@ div_impl_integer! { macro_rules! div_impl_float { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Div for $t { + impl Div for $t { type Output = $t; #[inline] fn div(self, other: $t) -> $t { self / other } } - forward_ref_binop! { impl const Div, div for $t, $t } + forward_ref_binop! { impl Div, div for $t, $t } )*) } @@ -526,7 +517,7 @@ div_impl_float! { f32 f64 } /// use std::ops::Rem; /// /// #[derive(PartialEq, Debug)] -/// struct SplitSlice<'a, T: 'a> { +/// struct SplitSlice<'a, T> { /// slice: &'a [T], /// } /// @@ -553,7 +544,6 @@ div_impl_float! { f32 f64 } label = "no implementation for `{Self} % {Rhs}`" )] #[doc(alias = "%")] -#[const_trait] pub trait Rem<Rhs = Self> { /// The resulting type after applying the `%` operator. #[stable(feature = "rust1", since = "1.0.0")] @@ -581,15 +571,14 @@ macro_rules! rem_impl_integer { /// #[doc = $panic] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Rem for $t { + impl Rem for $t { type Output = $t; #[inline] fn rem(self, other: $t) -> $t { self % other } } - forward_ref_binop! { impl const Rem, rem for $t, $t } + forward_ref_binop! { impl Rem, rem for $t, $t } )*)*) } @@ -616,15 +605,14 @@ macro_rules! rem_impl_float { /// assert_eq!(x % y, remainder); /// ``` #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Rem for $t { + impl Rem for $t { type Output = $t; #[inline] fn rem(self, other: $t) -> $t { self % other } } - forward_ref_binop! { impl const Rem, rem for $t, $t } + forward_ref_binop! { impl Rem, rem for $t, $t } )*) } @@ -669,7 +657,6 @@ rem_impl_float! { f32 f64 } #[lang = "neg"] #[stable(feature = "rust1", since = "1.0.0")] #[doc(alias = "-")] -#[const_trait] pub trait Neg { /// The resulting type after applying the `-` operator. #[stable(feature = "rust1", since = "1.0.0")] @@ -692,8 +679,7 @@ pub trait Neg { macro_rules! neg_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Neg for $t { + impl Neg for $t { type Output = $t; #[inline] @@ -701,7 +687,7 @@ macro_rules! neg_impl { fn neg(self) -> $t { -self } } - forward_ref_unop! { impl const Neg, neg for $t } + forward_ref_unop! { impl Neg, neg for $t } )*) } @@ -744,7 +730,6 @@ neg_impl! { isize i8 i16 i32 i64 i128 f32 f64 } )] #[doc(alias = "+")] #[doc(alias = "+=")] -#[const_trait] pub trait AddAssign<Rhs = Self> { /// Performs the `+=` operation. /// @@ -762,14 +747,13 @@ pub trait AddAssign<Rhs = Self> { macro_rules! add_assign_impl { ($($t:ty)+) => ($( #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const AddAssign for $t { + impl AddAssign for $t { #[inline] #[rustc_inherit_overflow_checks] fn add_assign(&mut self, other: $t) { *self += other } } - forward_ref_op_assign! { impl const AddAssign, add_assign for $t, $t } + forward_ref_op_assign! { impl AddAssign, add_assign for $t, $t } )+) } @@ -812,7 +796,6 @@ add_assign_impl! { usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 f32 f64 } )] #[doc(alias = "-")] #[doc(alias = "-=")] -#[const_trait] pub trait SubAssign<Rhs = Self> { /// Performs the `-=` operation. /// @@ -830,14 +813,13 @@ pub trait SubAssign<Rhs = Self> { macro_rules! sub_assign_impl { ($($t:ty)+) => ($( #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const SubAssign for $t { + impl SubAssign for $t { #[inline] #[rustc_inherit_overflow_checks] fn sub_assign(&mut self, other: $t) { *self -= other } } - forward_ref_op_assign! { impl const SubAssign, sub_assign for $t, $t } + forward_ref_op_assign! { impl SubAssign, sub_assign for $t, $t } )+) } @@ -871,7 +853,6 @@ sub_assign_impl! { usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 f32 f64 } )] #[doc(alias = "*")] #[doc(alias = "*=")] -#[const_trait] pub trait MulAssign<Rhs = Self> { /// Performs the `*=` operation. /// @@ -889,14 +870,13 @@ pub trait MulAssign<Rhs = Self> { macro_rules! mul_assign_impl { ($($t:ty)+) => ($( #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const MulAssign for $t { + impl MulAssign for $t { #[inline] #[rustc_inherit_overflow_checks] fn mul_assign(&mut self, other: $t) { *self *= other } } - forward_ref_op_assign! { impl const MulAssign, mul_assign for $t, $t } + forward_ref_op_assign! { impl MulAssign, mul_assign for $t, $t } )+) } @@ -930,7 +910,6 @@ mul_assign_impl! { usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 f32 f64 } )] #[doc(alias = "/")] #[doc(alias = "/=")] -#[const_trait] pub trait DivAssign<Rhs = Self> { /// Performs the `/=` operation. /// @@ -948,13 +927,12 @@ pub trait DivAssign<Rhs = Self> { macro_rules! div_assign_impl { ($($t:ty)+) => ($( #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const DivAssign for $t { + impl DivAssign for $t { #[inline] fn div_assign(&mut self, other: $t) { *self /= other } } - forward_ref_op_assign! { impl const DivAssign, div_assign for $t, $t } + forward_ref_op_assign! { impl DivAssign, div_assign for $t, $t } )+) } @@ -992,7 +970,6 @@ div_assign_impl! { usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 f32 f64 } )] #[doc(alias = "%")] #[doc(alias = "%=")] -#[const_trait] pub trait RemAssign<Rhs = Self> { /// Performs the `%=` operation. /// @@ -1010,13 +987,12 @@ pub trait RemAssign<Rhs = Self> { macro_rules! rem_assign_impl { ($($t:ty)+) => ($( #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const RemAssign for $t { + impl RemAssign for $t { #[inline] fn rem_assign(&mut self, other: $t) { *self %= other } } - forward_ref_op_assign! { impl const RemAssign, rem_assign for $t, $t } + forward_ref_op_assign! { impl RemAssign, rem_assign for $t, $t } )+) } diff --git a/library/core/src/ops/bit.rs b/library/core/src/ops/bit.rs index 327009801..c70f4a3da 100644 --- a/library/core/src/ops/bit.rs +++ b/library/core/src/ops/bit.rs @@ -31,7 +31,6 @@ #[lang = "not"] #[stable(feature = "rust1", since = "1.0.0")] #[doc(alias = "!")] -#[const_trait] pub trait Not { /// The resulting type after applying the `!` operator. #[stable(feature = "rust1", since = "1.0.0")] @@ -55,23 +54,21 @@ pub trait Not { macro_rules! not_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Not for $t { + impl Not for $t { type Output = $t; #[inline] fn not(self) -> $t { !self } } - forward_ref_unop! { impl const Not, not for $t } + forward_ref_unop! { impl Not, not for $t } )*) } not_impl! { bool usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 } #[stable(feature = "not_never", since = "1.60.0")] -#[rustc_const_unstable(feature = "const_ops", issue = "90080")] -impl const Not for ! { +impl Not for ! { type Output = !; #[inline] @@ -144,7 +141,6 @@ impl const Not for ! { message = "no implementation for `{Self} & {Rhs}`", label = "no implementation for `{Self} & {Rhs}`" )] -#[const_trait] pub trait BitAnd<Rhs = Self> { /// The resulting type after applying the `&` operator. #[stable(feature = "rust1", since = "1.0.0")] @@ -168,15 +164,14 @@ pub trait BitAnd<Rhs = Self> { macro_rules! bitand_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitAnd for $t { + impl BitAnd for $t { type Output = $t; #[inline] fn bitand(self, rhs: $t) -> $t { self & rhs } } - forward_ref_binop! { impl const BitAnd, bitand for $t, $t } + forward_ref_binop! { impl BitAnd, bitand for $t, $t } )*) } @@ -246,7 +241,6 @@ bitand_impl! { bool usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 } message = "no implementation for `{Self} | {Rhs}`", label = "no implementation for `{Self} | {Rhs}`" )] -#[const_trait] pub trait BitOr<Rhs = Self> { /// The resulting type after applying the `|` operator. #[stable(feature = "rust1", since = "1.0.0")] @@ -270,15 +264,14 @@ pub trait BitOr<Rhs = Self> { macro_rules! bitor_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitOr for $t { + impl BitOr for $t { type Output = $t; #[inline] fn bitor(self, rhs: $t) -> $t { self | rhs } } - forward_ref_binop! { impl const BitOr, bitor for $t, $t } + forward_ref_binop! { impl BitOr, bitor for $t, $t } )*) } @@ -348,7 +341,6 @@ bitor_impl! { bool usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 } message = "no implementation for `{Self} ^ {Rhs}`", label = "no implementation for `{Self} ^ {Rhs}`" )] -#[const_trait] pub trait BitXor<Rhs = Self> { /// The resulting type after applying the `^` operator. #[stable(feature = "rust1", since = "1.0.0")] @@ -372,15 +364,14 @@ pub trait BitXor<Rhs = Self> { macro_rules! bitxor_impl { ($($t:ty)*) => ($( #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitXor for $t { + impl BitXor for $t { type Output = $t; #[inline] fn bitxor(self, other: $t) -> $t { self ^ other } } - forward_ref_binop! { impl const BitXor, bitxor for $t, $t } + forward_ref_binop! { impl BitXor, bitxor for $t, $t } )*) } @@ -449,7 +440,6 @@ bitxor_impl! { bool usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 } message = "no implementation for `{Self} << {Rhs}`", label = "no implementation for `{Self} << {Rhs}`" )] -#[const_trait] pub trait Shl<Rhs = Self> { /// The resulting type after applying the `<<` operator. #[stable(feature = "rust1", since = "1.0.0")] @@ -471,8 +461,7 @@ pub trait Shl<Rhs = Self> { macro_rules! shl_impl { ($t:ty, $f:ty) => { #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Shl<$f> for $t { + impl Shl<$f> for $t { type Output = $t; #[inline] @@ -482,7 +471,7 @@ macro_rules! shl_impl { } } - forward_ref_binop! { impl const Shl, shl for $t, $f } + forward_ref_binop! { impl Shl, shl for $t, $f } }; } @@ -569,7 +558,6 @@ shl_impl_all! { u8 u16 u32 u64 u128 usize i8 i16 i32 i64 isize i128 } message = "no implementation for `{Self} >> {Rhs}`", label = "no implementation for `{Self} >> {Rhs}`" )] -#[const_trait] pub trait Shr<Rhs = Self> { /// The resulting type after applying the `>>` operator. #[stable(feature = "rust1", since = "1.0.0")] @@ -591,8 +579,7 @@ pub trait Shr<Rhs = Self> { macro_rules! shr_impl { ($t:ty, $f:ty) => { #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const Shr<$f> for $t { + impl Shr<$f> for $t { type Output = $t; #[inline] @@ -602,7 +589,7 @@ macro_rules! shr_impl { } } - forward_ref_binop! { impl const Shr, shr for $t, $f } + forward_ref_binop! { impl Shr, shr for $t, $f } }; } @@ -698,7 +685,6 @@ shr_impl_all! { u8 u16 u32 u64 u128 usize i8 i16 i32 i64 i128 isize } message = "no implementation for `{Self} &= {Rhs}`", label = "no implementation for `{Self} &= {Rhs}`" )] -#[const_trait] pub trait BitAndAssign<Rhs = Self> { /// Performs the `&=` operation. /// @@ -728,13 +714,12 @@ pub trait BitAndAssign<Rhs = Self> { macro_rules! bitand_assign_impl { ($($t:ty)+) => ($( #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitAndAssign for $t { + impl BitAndAssign for $t { #[inline] fn bitand_assign(&mut self, other: $t) { *self &= other } } - forward_ref_op_assign! { impl const BitAndAssign, bitand_assign for $t, $t } + forward_ref_op_assign! { impl BitAndAssign, bitand_assign for $t, $t } )+) } @@ -771,7 +756,6 @@ bitand_assign_impl! { bool usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 } message = "no implementation for `{Self} |= {Rhs}`", label = "no implementation for `{Self} |= {Rhs}`" )] -#[const_trait] pub trait BitOrAssign<Rhs = Self> { /// Performs the `|=` operation. /// @@ -801,13 +785,12 @@ pub trait BitOrAssign<Rhs = Self> { macro_rules! bitor_assign_impl { ($($t:ty)+) => ($( #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitOrAssign for $t { + impl BitOrAssign for $t { #[inline] fn bitor_assign(&mut self, other: $t) { *self |= other } } - forward_ref_op_assign! { impl const BitOrAssign, bitor_assign for $t, $t } + forward_ref_op_assign! { impl BitOrAssign, bitor_assign for $t, $t } )+) } @@ -844,7 +827,6 @@ bitor_assign_impl! { bool usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 } message = "no implementation for `{Self} ^= {Rhs}`", label = "no implementation for `{Self} ^= {Rhs}`" )] -#[const_trait] pub trait BitXorAssign<Rhs = Self> { /// Performs the `^=` operation. /// @@ -874,13 +856,12 @@ pub trait BitXorAssign<Rhs = Self> { macro_rules! bitxor_assign_impl { ($($t:ty)+) => ($( #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const BitXorAssign for $t { + impl BitXorAssign for $t { #[inline] fn bitxor_assign(&mut self, other: $t) { *self ^= other } } - forward_ref_op_assign! { impl const BitXorAssign, bitxor_assign for $t, $t } + forward_ref_op_assign! { impl BitXorAssign, bitxor_assign for $t, $t } )+) } @@ -915,7 +896,6 @@ bitxor_assign_impl! { bool usize u8 u16 u32 u64 u128 isize i8 i16 i32 i64 i128 } message = "no implementation for `{Self} <<= {Rhs}`", label = "no implementation for `{Self} <<= {Rhs}`" )] -#[const_trait] pub trait ShlAssign<Rhs = Self> { /// Performs the `<<=` operation. /// @@ -937,8 +917,7 @@ pub trait ShlAssign<Rhs = Self> { macro_rules! shl_assign_impl { ($t:ty, $f:ty) => { #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const ShlAssign<$f> for $t { + impl ShlAssign<$f> for $t { #[inline] #[rustc_inherit_overflow_checks] fn shl_assign(&mut self, other: $f) { @@ -946,7 +925,7 @@ macro_rules! shl_assign_impl { } } - forward_ref_op_assign! { impl const ShlAssign, shl_assign for $t, $f } + forward_ref_op_assign! { impl ShlAssign, shl_assign for $t, $f } }; } @@ -999,7 +978,6 @@ shl_assign_impl_all! { u8 u16 u32 u64 u128 usize i8 i16 i32 i64 i128 isize } message = "no implementation for `{Self} >>= {Rhs}`", label = "no implementation for `{Self} >>= {Rhs}`" )] -#[const_trait] pub trait ShrAssign<Rhs = Self> { /// Performs the `>>=` operation. /// @@ -1021,8 +999,7 @@ pub trait ShrAssign<Rhs = Self> { macro_rules! shr_assign_impl { ($t:ty, $f:ty) => { #[stable(feature = "op_assign_traits", since = "1.8.0")] - #[rustc_const_unstable(feature = "const_ops", issue = "90080")] - impl const ShrAssign<$f> for $t { + impl ShrAssign<$f> for $t { #[inline] #[rustc_inherit_overflow_checks] fn shr_assign(&mut self, other: $f) { @@ -1030,7 +1007,7 @@ macro_rules! shr_assign_impl { } } - forward_ref_op_assign! { impl const ShrAssign, shr_assign for $t, $f } + forward_ref_op_assign! { impl ShrAssign, shr_assign for $t, $f } }; } diff --git a/library/core/src/ops/control_flow.rs b/library/core/src/ops/control_flow.rs index 117706fb4..e10c438ef 100644 --- a/library/core/src/ops/control_flow.rs +++ b/library/core/src/ops/control_flow.rs @@ -97,8 +97,7 @@ pub enum ControlFlow<B, C = ()> { } #[unstable(feature = "try_trait_v2", issue = "84277")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<B, C> const ops::Try for ControlFlow<B, C> { +impl<B, C> ops::Try for ControlFlow<B, C> { type Output = C; type Residual = ControlFlow<B, convert::Infallible>; @@ -117,8 +116,7 @@ impl<B, C> const ops::Try for ControlFlow<B, C> { } #[unstable(feature = "try_trait_v2", issue = "84277")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<B, C> const ops::FromResidual for ControlFlow<B, C> { +impl<B, C> ops::FromResidual for ControlFlow<B, C> { #[inline] fn from_residual(residual: ControlFlow<B, convert::Infallible>) -> Self { match residual { @@ -128,8 +126,7 @@ impl<B, C> const ops::FromResidual for ControlFlow<B, C> { } #[unstable(feature = "try_trait_v2_residual", issue = "91285")] -#[rustc_const_unstable(feature = "const_try", issue = "74935")] -impl<B, C> const ops::Residual<C> for ControlFlow<B, convert::Infallible> { +impl<B, C> ops::Residual<C> for ControlFlow<B, convert::Infallible> { type TryType = ControlFlow<B, C>; } diff --git a/library/core/src/ops/deref.rs b/library/core/src/ops/deref.rs index c67867f44..08c35b6da 100644 --- a/library/core/src/ops/deref.rs +++ b/library/core/src/ops/deref.rs @@ -61,7 +61,6 @@ #[doc(alias = "&*")] #[stable(feature = "rust1", since = "1.0.0")] #[rustc_diagnostic_item = "Deref"] -#[const_trait] pub trait Deref { /// The resulting type after dereferencing. #[stable(feature = "rust1", since = "1.0.0")] @@ -77,8 +76,7 @@ pub trait Deref { } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_deref", issue = "88955")] -impl<T: ?Sized> const Deref for &T { +impl<T: ?Sized> Deref for &T { type Target = T; #[rustc_diagnostic_item = "noop_method_deref"] @@ -91,8 +89,7 @@ impl<T: ?Sized> const Deref for &T { impl<T: ?Sized> !DerefMut for &T {} #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_deref", issue = "88955")] -impl<T: ?Sized> const Deref for &mut T { +impl<T: ?Sized> Deref for &mut T { type Target = T; fn deref(&self) -> &T { @@ -170,7 +167,6 @@ impl<T: ?Sized> const Deref for &mut T { #[lang = "deref_mut"] #[doc(alias = "*")] #[stable(feature = "rust1", since = "1.0.0")] -#[const_trait] pub trait DerefMut: Deref { /// Mutably dereferences the value. #[stable(feature = "rust1", since = "1.0.0")] diff --git a/library/core/src/ops/drop.rs b/library/core/src/ops/drop.rs index a2c3d978c..9ebf426be 100644 --- a/library/core/src/ops/drop.rs +++ b/library/core/src/ops/drop.rs @@ -132,6 +132,74 @@ /// are `Copy` get implicitly duplicated by the compiler, making it very /// hard to predict when, and how often destructors will be executed. As such, /// these types cannot have destructors. +/// +/// ## Drop check +/// +/// Dropping interacts with the borrow checker in subtle ways: when a type `T` is being implicitly +/// dropped as some variable of this type goes out of scope, the borrow checker needs to ensure that +/// calling `T`'s destructor at this moment is safe. In particular, it also needs to be safe to +/// recursively drop all the fields of `T`. For example, it is crucial that code like the following +/// is being rejected: +/// +/// ```compile_fail,E0597 +/// use std::cell::Cell; +/// +/// struct S<'a>(Cell<Option<&'a S<'a>>>, Box<i32>); +/// impl Drop for S<'_> { +/// fn drop(&mut self) { +/// if let Some(r) = self.0.get() { +/// // Print the contents of the `Box` in `r`. +/// println!("{}", r.1); +/// } +/// } +/// } +/// +/// fn main() { +/// // Set up two `S` that point to each other. +/// let s1 = S(Cell::new(None), Box::new(42)); +/// let s2 = S(Cell::new(Some(&s1)), Box::new(42)); +/// s1.0.set(Some(&s2)); +/// // Now they both get dropped. But whichever is the 2nd one +/// // to be dropped will access the `Box` in the first one, +/// // which is a use-after-free! +/// } +/// ``` +/// +/// The Nomicon discusses the need for [drop check in more detail][drop check]. +/// +/// To reject such code, the "drop check" analysis determines which types and lifetimes need to +/// still be live when `T` gets dropped. The exact details of this analysis are not yet +/// stably guaranteed and **subject to change**. Currently, the analysis works as follows: +/// - If `T` has no drop glue, then trivially nothing is required to be live. This is the case if +/// neither `T` nor any of its (recursive) fields have a destructor (`impl Drop`). [`PhantomData`] +/// and [`ManuallyDrop`] are considered to never have a destructor, no matter their field type. +/// - If `T` has drop glue, then, for all types `U` that are *owned* by any field of `T`, +/// recursively add the types and lifetimes that need to be live when `U` gets dropped. The set of +/// owned types is determined by recursively traversing `T`: +/// - Recursively descend through `PhantomData`, `Box`, tuples, and arrays (including arrays of +/// length 0). +/// - Stop at reference and raw pointer types as well as function pointers and function items; +/// they do not own anything. +/// - Stop at non-composite types (type parameters that remain generic in the current context and +/// base types such as integers and `bool`); these types are owned. +/// - When hitting an ADT with `impl Drop`, stop there; this type is owned. +/// - When hitting an ADT without `impl Drop`, recursively descend to its fields. (For an `enum`, +/// consider all fields of all variants.) +/// - Furthermore, if `T` implements `Drop`, then all generic (lifetime and type) parameters of `T` +/// must be live. +/// +/// In the above example, the last clause implies that `'a` must be live when `S<'a>` is dropped, +/// and hence the example is rejected. If we remove the `impl Drop`, the liveness requirement +/// disappears and the example is accepted. +/// +/// There exists an unstable way for a type to opt-out of the last clause; this is called "drop +/// check eyepatch" or `may_dangle`. For more details on this nightly-only feature, see the +/// [discussion in the Nomicon][nomicon]. +/// +/// [`ManuallyDrop`]: crate::mem::ManuallyDrop +/// [`PhantomData`]: crate::marker::PhantomData +/// [drop check]: ../../nomicon/dropck.html +/// [nomicon]: ../../nomicon/phantom-data.html#an-exception-the-special-case-of-the-standard-library-and-its-unstable-may_dangle #[lang = "drop"] #[stable(feature = "rust1", since = "1.0.0")] #[const_trait] diff --git a/library/core/src/ops/function.rs b/library/core/src/ops/function.rs index b7e1aee9d..67c8245f0 100644 --- a/library/core/src/ops/function.rs +++ b/library/core/src/ops/function.rs @@ -254,10 +254,9 @@ mod impls { use crate::marker::Tuple; #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")] - impl<A: Tuple, F: ?Sized> const Fn<A> for &F + impl<A: Tuple, F: ?Sized> Fn<A> for &F where - F: ~const Fn<A>, + F: Fn<A>, { extern "rust-call" fn call(&self, args: A) -> F::Output { (**self).call(args) @@ -265,10 +264,9 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")] - impl<A: Tuple, F: ?Sized> const FnMut<A> for &F + impl<A: Tuple, F: ?Sized> FnMut<A> for &F where - F: ~const Fn<A>, + F: Fn<A>, { extern "rust-call" fn call_mut(&mut self, args: A) -> F::Output { (**self).call(args) @@ -276,10 +274,9 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")] - impl<A: Tuple, F: ?Sized> const FnOnce<A> for &F + impl<A: Tuple, F: ?Sized> FnOnce<A> for &F where - F: ~const Fn<A>, + F: Fn<A>, { type Output = F::Output; @@ -289,10 +286,9 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")] - impl<A: Tuple, F: ?Sized> const FnMut<A> for &mut F + impl<A: Tuple, F: ?Sized> FnMut<A> for &mut F where - F: ~const FnMut<A>, + F: FnMut<A>, { extern "rust-call" fn call_mut(&mut self, args: A) -> F::Output { (*self).call_mut(args) @@ -300,10 +296,9 @@ mod impls { } #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_fn_trait_ref_impls", issue = "101803")] - impl<A: Tuple, F: ?Sized> const FnOnce<A> for &mut F + impl<A: Tuple, F: ?Sized> FnOnce<A> for &mut F where - F: ~const FnMut<A>, + F: FnMut<A>, { type Output = F::Output; extern "rust-call" fn call_once(self, args: A) -> F::Output { diff --git a/library/core/src/ops/index.rs b/library/core/src/ops/index.rs index 228efb0bc..1f1784ec9 100644 --- a/library/core/src/ops/index.rs +++ b/library/core/src/ops/index.rs @@ -55,10 +55,10 @@ #[doc(alias = "]")] #[doc(alias = "[")] #[doc(alias = "[]")] -#[const_trait] pub trait Index<Idx: ?Sized> { /// The returned type after indexing. #[stable(feature = "rust1", since = "1.0.0")] + #[rustc_diagnostic_item = "IndexOutput"] type Output: ?Sized; /// Performs the indexing (`container[index]`) operation. @@ -164,8 +164,7 @@ see chapter in The Book <https://doc.rust-lang.org/book/ch08-02-strings.html#ind #[doc(alias = "[")] #[doc(alias = "]")] #[doc(alias = "[]")] -#[const_trait] -pub trait IndexMut<Idx: ?Sized>: ~const Index<Idx> { +pub trait IndexMut<Idx: ?Sized>: Index<Idx> { /// Performs the mutable indexing (`container[index]`) operation. /// /// # Panics diff --git a/library/core/src/ops/range.rs b/library/core/src/ops/range.rs index b8ab26564..ba5e6ddc7 100644 --- a/library/core/src/ops/range.rs +++ b/library/core/src/ops/range.rs @@ -96,7 +96,7 @@ impl<Idx: fmt::Debug> fmt::Debug for Range<Idx> { } } -impl<Idx: ~const PartialOrd<Idx>> Range<Idx> { +impl<Idx: PartialOrd<Idx>> Range<Idx> { /// Returns `true` if `item` is contained in the range. /// /// # Examples @@ -116,11 +116,10 @@ impl<Idx: ~const PartialOrd<Idx>> Range<Idx> { /// assert!(!(f32::NAN..1.0).contains(&0.5)); /// ``` #[stable(feature = "range_contains", since = "1.35.0")] - #[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] - pub const fn contains<U>(&self, item: &U) -> bool + pub fn contains<U>(&self, item: &U) -> bool where - Idx: ~const PartialOrd<U>, - U: ?Sized + ~const PartialOrd<Idx>, + Idx: PartialOrd<U>, + U: ?Sized + PartialOrd<Idx>, { <Self as RangeBounds<Idx>>::contains(self, item) } @@ -143,8 +142,7 @@ impl<Idx: ~const PartialOrd<Idx>> Range<Idx> { /// assert!( (f32::NAN..5.0).is_empty()); /// ``` #[stable(feature = "range_is_empty", since = "1.47.0")] - #[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] - pub const fn is_empty(&self) -> bool { + pub fn is_empty(&self) -> bool { !(self.start < self.end) } } @@ -201,7 +199,7 @@ impl<Idx: fmt::Debug> fmt::Debug for RangeFrom<Idx> { } } -impl<Idx: ~const PartialOrd<Idx>> RangeFrom<Idx> { +impl<Idx: PartialOrd<Idx>> RangeFrom<Idx> { /// Returns `true` if `item` is contained in the range. /// /// # Examples @@ -216,11 +214,10 @@ impl<Idx: ~const PartialOrd<Idx>> RangeFrom<Idx> { /// assert!(!(f32::NAN..).contains(&0.5)); /// ``` #[stable(feature = "range_contains", since = "1.35.0")] - #[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] - pub const fn contains<U>(&self, item: &U) -> bool + pub fn contains<U>(&self, item: &U) -> bool where - Idx: ~const PartialOrd<U>, - U: ?Sized + ~const PartialOrd<Idx>, + Idx: PartialOrd<U>, + U: ?Sized + PartialOrd<Idx>, { <Self as RangeBounds<Idx>>::contains(self, item) } @@ -283,7 +280,7 @@ impl<Idx: fmt::Debug> fmt::Debug for RangeTo<Idx> { } } -impl<Idx: ~const PartialOrd<Idx>> RangeTo<Idx> { +impl<Idx: PartialOrd<Idx>> RangeTo<Idx> { /// Returns `true` if `item` is contained in the range. /// /// # Examples @@ -298,11 +295,10 @@ impl<Idx: ~const PartialOrd<Idx>> RangeTo<Idx> { /// assert!(!(..f32::NAN).contains(&0.5)); /// ``` #[stable(feature = "range_contains", since = "1.35.0")] - #[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] - pub const fn contains<U>(&self, item: &U) -> bool + pub fn contains<U>(&self, item: &U) -> bool where - Idx: ~const PartialOrd<U>, - U: ?Sized + ~const PartialOrd<Idx>, + Idx: PartialOrd<U>, + U: ?Sized + PartialOrd<Idx>, { <Self as RangeBounds<Idx>>::contains(self, item) } @@ -474,7 +470,7 @@ impl<Idx: fmt::Debug> fmt::Debug for RangeInclusive<Idx> { } } -impl<Idx: ~const PartialOrd<Idx>> RangeInclusive<Idx> { +impl<Idx: PartialOrd<Idx>> RangeInclusive<Idx> { /// Returns `true` if `item` is contained in the range. /// /// # Examples @@ -505,11 +501,10 @@ impl<Idx: ~const PartialOrd<Idx>> RangeInclusive<Idx> { /// assert!(!r.contains(&3) && !r.contains(&5)); /// ``` #[stable(feature = "range_contains", since = "1.35.0")] - #[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] - pub const fn contains<U>(&self, item: &U) -> bool + pub fn contains<U>(&self, item: &U) -> bool where - Idx: ~const PartialOrd<U>, - U: ?Sized + ~const PartialOrd<Idx>, + Idx: PartialOrd<U>, + U: ?Sized + PartialOrd<Idx>, { <Self as RangeBounds<Idx>>::contains(self, item) } @@ -541,9 +536,8 @@ impl<Idx: ~const PartialOrd<Idx>> RangeInclusive<Idx> { /// assert!(r.is_empty()); /// ``` #[stable(feature = "range_is_empty", since = "1.47.0")] - #[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] #[inline] - pub const fn is_empty(&self) -> bool { + pub fn is_empty(&self) -> bool { self.exhausted || !(self.start <= self.end) } } @@ -605,7 +599,7 @@ impl<Idx: fmt::Debug> fmt::Debug for RangeToInclusive<Idx> { } } -impl<Idx: ~const PartialOrd<Idx>> RangeToInclusive<Idx> { +impl<Idx: PartialOrd<Idx>> RangeToInclusive<Idx> { /// Returns `true` if `item` is contained in the range. /// /// # Examples @@ -620,11 +614,10 @@ impl<Idx: ~const PartialOrd<Idx>> RangeToInclusive<Idx> { /// assert!(!(..=f32::NAN).contains(&0.5)); /// ``` #[stable(feature = "range_contains", since = "1.35.0")] - #[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] - pub const fn contains<U>(&self, item: &U) -> bool + pub fn contains<U>(&self, item: &U) -> bool where - Idx: ~const PartialOrd<U>, - U: ?Sized + ~const PartialOrd<Idx>, + Idx: PartialOrd<U>, + U: ?Sized + PartialOrd<Idx>, { <Self as RangeBounds<Idx>>::contains(self, item) } @@ -765,7 +758,6 @@ impl<T: Clone> Bound<&T> { /// `RangeBounds` is implemented by Rust's built-in range types, produced /// by range syntax like `..`, `a..`, `..b`, `..=c`, `d..e`, or `f..=g`. #[stable(feature = "collections_range", since = "1.28.0")] -#[const_trait] pub trait RangeBounds<T: ?Sized> { /// Start index bound. /// @@ -818,8 +810,8 @@ pub trait RangeBounds<T: ?Sized> { #[stable(feature = "range_contains", since = "1.35.0")] fn contains<U>(&self, item: &U) -> bool where - T: ~const PartialOrd<U>, - U: ?Sized + ~const PartialOrd<T>, + T: PartialOrd<U>, + U: ?Sized + PartialOrd<T>, { (match self.start_bound() { Included(start) => start <= item, @@ -836,8 +828,7 @@ pub trait RangeBounds<T: ?Sized> { use self::Bound::{Excluded, Included, Unbounded}; #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<T: ?Sized> const RangeBounds<T> for RangeFull { +impl<T: ?Sized> RangeBounds<T> for RangeFull { fn start_bound(&self) -> Bound<&T> { Unbounded } @@ -847,8 +838,7 @@ impl<T: ?Sized> const RangeBounds<T> for RangeFull { } #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<T> const RangeBounds<T> for RangeFrom<T> { +impl<T> RangeBounds<T> for RangeFrom<T> { fn start_bound(&self) -> Bound<&T> { Included(&self.start) } @@ -858,8 +848,7 @@ impl<T> const RangeBounds<T> for RangeFrom<T> { } #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<T> const RangeBounds<T> for RangeTo<T> { +impl<T> RangeBounds<T> for RangeTo<T> { fn start_bound(&self) -> Bound<&T> { Unbounded } @@ -869,8 +858,7 @@ impl<T> const RangeBounds<T> for RangeTo<T> { } #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<T> const RangeBounds<T> for Range<T> { +impl<T> RangeBounds<T> for Range<T> { fn start_bound(&self) -> Bound<&T> { Included(&self.start) } @@ -880,8 +868,7 @@ impl<T> const RangeBounds<T> for Range<T> { } #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<T> const RangeBounds<T> for RangeInclusive<T> { +impl<T> RangeBounds<T> for RangeInclusive<T> { fn start_bound(&self) -> Bound<&T> { Included(&self.start) } @@ -897,8 +884,7 @@ impl<T> const RangeBounds<T> for RangeInclusive<T> { } #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<T> const RangeBounds<T> for RangeToInclusive<T> { +impl<T> RangeBounds<T> for RangeToInclusive<T> { fn start_bound(&self) -> Bound<&T> { Unbounded } @@ -908,8 +894,7 @@ impl<T> const RangeBounds<T> for RangeToInclusive<T> { } #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<T> const RangeBounds<T> for (Bound<T>, Bound<T>) { +impl<T> RangeBounds<T> for (Bound<T>, Bound<T>) { fn start_bound(&self) -> Bound<&T> { match *self { (Included(ref start), _) => Included(start), @@ -928,8 +913,7 @@ impl<T> const RangeBounds<T> for (Bound<T>, Bound<T>) { } #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<'a, T: ?Sized + 'a> const RangeBounds<T> for (Bound<&'a T>, Bound<&'a T>) { +impl<'a, T: ?Sized + 'a> RangeBounds<T> for (Bound<&'a T>, Bound<&'a T>) { fn start_bound(&self) -> Bound<&T> { self.0 } @@ -940,8 +924,7 @@ impl<'a, T: ?Sized + 'a> const RangeBounds<T> for (Bound<&'a T>, Bound<&'a T>) { } #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<T> const RangeBounds<T> for RangeFrom<&T> { +impl<T> RangeBounds<T> for RangeFrom<&T> { fn start_bound(&self) -> Bound<&T> { Included(self.start) } @@ -951,8 +934,7 @@ impl<T> const RangeBounds<T> for RangeFrom<&T> { } #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<T> const RangeBounds<T> for RangeTo<&T> { +impl<T> RangeBounds<T> for RangeTo<&T> { fn start_bound(&self) -> Bound<&T> { Unbounded } @@ -962,8 +944,7 @@ impl<T> const RangeBounds<T> for RangeTo<&T> { } #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<T> const RangeBounds<T> for Range<&T> { +impl<T> RangeBounds<T> for Range<&T> { fn start_bound(&self) -> Bound<&T> { Included(self.start) } @@ -973,8 +954,7 @@ impl<T> const RangeBounds<T> for Range<&T> { } #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<T> const RangeBounds<T> for RangeInclusive<&T> { +impl<T> RangeBounds<T> for RangeInclusive<&T> { fn start_bound(&self) -> Bound<&T> { Included(self.start) } @@ -984,8 +964,7 @@ impl<T> const RangeBounds<T> for RangeInclusive<&T> { } #[stable(feature = "collections_range", since = "1.28.0")] -#[rustc_const_unstable(feature = "const_range_bounds", issue = "108082")] -impl<T> const RangeBounds<T> for RangeToInclusive<&T> { +impl<T> RangeBounds<T> for RangeToInclusive<&T> { fn start_bound(&self) -> Bound<&T> { Unbounded } diff --git a/library/core/src/ops/try_trait.rs b/library/core/src/ops/try_trait.rs index c254803fb..b4f69d0b2 100644 --- a/library/core/src/ops/try_trait.rs +++ b/library/core/src/ops/try_trait.rs @@ -128,8 +128,7 @@ use crate::ops::ControlFlow; )] #[doc(alias = "?")] #[lang = "Try"] -#[const_trait] -pub trait Try: ~const FromResidual { +pub trait Try: FromResidual { /// The type of the value produced by `?` when *not* short-circuiting. #[unstable(feature = "try_trait_v2", issue = "84277")] type Output; @@ -305,7 +304,6 @@ pub trait Try: ~const FromResidual { )] #[rustc_diagnostic_item = "FromResidual"] #[unstable(feature = "try_trait_v2", issue = "84277")] -#[const_trait] pub trait FromResidual<R = <Self as Try>::Residual> { /// Constructs the type from a compatible `Residual` type. /// @@ -358,11 +356,10 @@ where /// and in the other direction, /// `<Result<Infallible, E> as Residual<T>>::TryType = Result<T, E>`. #[unstable(feature = "try_trait_v2_residual", issue = "91285")] -#[const_trait] pub trait Residual<O> { /// The "return" type of this meta-function. #[unstable(feature = "try_trait_v2_residual", issue = "91285")] - type TryType: ~const Try<Output = O, Residual = Self>; + type TryType: Try<Output = O, Residual = Self>; } #[unstable(feature = "pub_crate_should_not_need_unstable_attr", issue = "none")] @@ -389,16 +386,14 @@ impl<T> NeverShortCircuit<T> { } #[inline] - pub fn wrap_mut_2<A, B>( - mut f: impl ~const FnMut(A, B) -> T, - ) -> impl ~const FnMut(A, B) -> Self { - const move |a, b| NeverShortCircuit(f(a, b)) + pub fn wrap_mut_2<A, B>(mut f: impl FnMut(A, B) -> T) -> impl FnMut(A, B) -> Self { + move |a, b| NeverShortCircuit(f(a, b)) } } pub(crate) enum NeverShortCircuitResidual {} -impl<T> const Try for NeverShortCircuit<T> { +impl<T> Try for NeverShortCircuit<T> { type Output = T; type Residual = NeverShortCircuitResidual; @@ -413,14 +408,14 @@ impl<T> const Try for NeverShortCircuit<T> { } } -impl<T> const FromResidual for NeverShortCircuit<T> { +impl<T> FromResidual for NeverShortCircuit<T> { #[inline] fn from_residual(never: NeverShortCircuitResidual) -> Self { match never {} } } -impl<T> const Residual<T> for NeverShortCircuitResidual { +impl<T> Residual<T> for NeverShortCircuitResidual { type TryType = NeverShortCircuit<T>; } diff --git a/library/core/src/option.rs b/library/core/src/option.rs index 6f7bc6ed2..ec1ef3cf4 100644 --- a/library/core/src/option.rs +++ b/library/core/src/option.rs @@ -547,7 +547,6 @@ #![stable(feature = "rust1", since = "1.0.0")] use crate::iter::{self, FromIterator, FusedIterator, TrustedLen}; -use crate::marker::Destruct; use crate::panicking::{panic, panic_str}; use crate::pin::Pin; use crate::{ @@ -559,7 +558,7 @@ use crate::{ /// The `Option` type. See [the module level documentation](self) for more. #[derive(Copy, PartialOrd, Eq, Ord, Debug, Hash)] #[rustc_diagnostic_item = "Option"] -#[cfg_attr(not(bootstrap), lang = "Option")] +#[lang = "Option"] #[stable(feature = "rust1", since = "1.0.0")] pub enum Option<T> { /// No value. @@ -766,13 +765,6 @@ impl<T> Option<T> { #[must_use] #[unstable(feature = "option_as_slice", issue = "108545")] pub fn as_slice(&self) -> &[T] { - #[cfg(bootstrap)] - match self { - Some(value) => slice::from_ref(value), - None => &[], - } - - #[cfg(not(bootstrap))] // SAFETY: When the `Option` is `Some`, we're using the actual pointer // to the payload, with a length of 1, so this is equivalent to // `slice::from_ref`, and thus is safe. @@ -833,13 +825,6 @@ impl<T> Option<T> { #[must_use] #[unstable(feature = "option_as_slice", issue = "108545")] pub fn as_mut_slice(&mut self) -> &mut [T] { - #[cfg(bootstrap)] - match self { - Some(value) => slice::from_mut(value), - None => &mut [], - } - - #[cfg(not(bootstrap))] // SAFETY: When the `Option` is `Some`, we're using the actual pointer // to the payload, with a length of 1, so this is equivalent to // `slice::from_mut`, and thus is safe. @@ -967,11 +952,7 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn unwrap_or(self, default: T) -> T - where - T: ~const Destruct, - { + pub fn unwrap_or(self, default: T) -> T { match self { Some(x) => x, None => default, @@ -989,11 +970,9 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn unwrap_or_else<F>(self, f: F) -> T + pub fn unwrap_or_else<F>(self, f: F) -> T where - F: ~const FnOnce() -> T, - F: ~const Destruct, + F: FnOnce() -> T, { match self { Some(x) => x, @@ -1022,14 +1001,13 @@ impl<T> Option<T> { /// [`FromStr`]: crate::str::FromStr #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn unwrap_or_default(self) -> T + pub fn unwrap_or_default(self) -> T where - T: ~const Default, + T: Default, { match self { Some(x) => x, - None => Default::default(), + None => T::default(), } } @@ -1089,11 +1067,9 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn map<U, F>(self, f: F) -> Option<U> + pub fn map<U, F>(self, f: F) -> Option<U> where - F: ~const FnOnce(T) -> U, - F: ~const Destruct, + F: FnOnce(T) -> U, { match self { Some(x) => Some(f(x)), @@ -1118,11 +1094,9 @@ impl<T> Option<T> { /// ``` #[inline] #[unstable(feature = "result_option_inspect", issue = "91345")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn inspect<F>(self, f: F) -> Self + pub fn inspect<F>(self, f: F) -> Self where - F: ~const FnOnce(&T), - F: ~const Destruct, + F: FnOnce(&T), { if let Some(ref x) = self { f(x); @@ -1151,12 +1125,9 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn map_or<U, F>(self, default: U, f: F) -> U + pub fn map_or<U, F>(self, default: U, f: F) -> U where - F: ~const FnOnce(T) -> U, - F: ~const Destruct, - U: ~const Destruct, + F: FnOnce(T) -> U, { match self { Some(t) => f(t), @@ -1180,13 +1151,10 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn map_or_else<U, D, F>(self, default: D, f: F) -> U + pub fn map_or_else<U, D, F>(self, default: D, f: F) -> U where - D: ~const FnOnce() -> U, - D: ~const Destruct, - F: ~const FnOnce(T) -> U, - F: ~const Destruct, + D: FnOnce() -> U, + F: FnOnce(T) -> U, { match self { Some(t) => f(t), @@ -1217,11 +1185,7 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn ok_or<E>(self, err: E) -> Result<T, E> - where - E: ~const Destruct, - { + pub fn ok_or<E>(self, err: E) -> Result<T, E> { match self { Some(v) => Ok(v), None => Err(err), @@ -1246,11 +1210,9 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn ok_or_else<E, F>(self, err: F) -> Result<T, E> + pub fn ok_or_else<E, F>(self, err: F) -> Result<T, E> where - F: ~const FnOnce() -> E, - F: ~const Destruct, + F: FnOnce() -> E, { match self { Some(v) => Ok(v), @@ -1274,10 +1236,9 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "option_deref", since = "1.40.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn as_deref(&self) -> Option<&T::Target> + pub fn as_deref(&self) -> Option<&T::Target> where - T: ~const Deref, + T: Deref, { match self.as_ref() { Some(t) => Some(t.deref()), @@ -1301,10 +1262,9 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "option_deref", since = "1.40.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn as_deref_mut(&mut self) -> Option<&mut T::Target> + pub fn as_deref_mut(&mut self) -> Option<&mut T::Target> where - T: ~const DerefMut, + T: DerefMut, { match self.as_mut() { Some(t) => Some(t.deref_mut()), @@ -1388,12 +1348,7 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn and<U>(self, optb: Option<U>) -> Option<U> - where - T: ~const Destruct, - U: ~const Destruct, - { + pub fn and<U>(self, optb: Option<U>) -> Option<U> { match self { Some(_) => optb, None => None, @@ -1430,11 +1385,9 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn and_then<U, F>(self, f: F) -> Option<U> + pub fn and_then<U, F>(self, f: F) -> Option<U> where - F: ~const FnOnce(T) -> Option<U>, - F: ~const Destruct, + F: FnOnce(T) -> Option<U>, { match self { Some(x) => f(x), @@ -1468,12 +1421,9 @@ impl<T> Option<T> { /// [`Some(t)`]: Some #[inline] #[stable(feature = "option_filter", since = "1.27.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn filter<P>(self, predicate: P) -> Self + pub fn filter<P>(self, predicate: P) -> Self where - T: ~const Destruct, - P: ~const FnOnce(&T) -> bool, - P: ~const Destruct, + P: FnOnce(&T) -> bool, { if let Some(x) = self { if predicate(&x) { @@ -1512,11 +1462,7 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn or(self, optb: Option<T>) -> Option<T> - where - T: ~const Destruct, - { + pub fn or(self, optb: Option<T>) -> Option<T> { match self { Some(x) => Some(x), None => optb, @@ -1538,11 +1484,9 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn or_else<F>(self, f: F) -> Option<T> + pub fn or_else<F>(self, f: F) -> Option<T> where - F: ~const FnOnce() -> Option<T>, - F: ~const Destruct, + F: FnOnce() -> Option<T>, { match self { Some(x) => Some(x), @@ -1573,11 +1517,7 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "option_xor", since = "1.37.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn xor(self, optb: Option<T>) -> Option<T> - where - T: ~const Destruct, - { + pub fn xor(self, optb: Option<T>) -> Option<T> { match (self, optb) { (Some(a), None) => Some(a), (None, Some(b)) => Some(b), @@ -1611,11 +1551,7 @@ impl<T> Option<T> { #[must_use = "if you intended to set a value, consider assignment instead"] #[inline] #[stable(feature = "option_insert", since = "1.53.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn insert(&mut self, value: T) -> &mut T - where - T: ~const Destruct, - { + pub fn insert(&mut self, value: T) -> &mut T { *self = Some(value); // SAFETY: the code above just filled the option @@ -1644,11 +1580,7 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "option_entry", since = "1.20.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn get_or_insert(&mut self, value: T) -> &mut T - where - T: ~const Destruct, - { + pub fn get_or_insert(&mut self, value: T) -> &mut T { if let None = *self { *self = Some(value); } @@ -1679,16 +1611,11 @@ impl<T> Option<T> { /// ``` #[inline] #[unstable(feature = "option_get_or_insert_default", issue = "82901")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn get_or_insert_default(&mut self) -> &mut T + pub fn get_or_insert_default(&mut self) -> &mut T where - T: ~const Default, + T: Default, { - const fn default<T: ~const Default>() -> T { - T::default() - } - - self.get_or_insert_with(default) + self.get_or_insert_with(T::default) } /// Inserts a value computed from `f` into the option if it is [`None`], @@ -1710,16 +1637,12 @@ impl<T> Option<T> { /// ``` #[inline] #[stable(feature = "option_entry", since = "1.20.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn get_or_insert_with<F>(&mut self, f: F) -> &mut T + pub fn get_or_insert_with<F>(&mut self, f: F) -> &mut T where - F: ~const FnOnce() -> T, - F: ~const Destruct, + F: FnOnce() -> T, { - if let None = *self { - // the compiler isn't smart enough to know that we are not dropping a `T` - // here and wants us to ensure `T` can be dropped at compile time. - mem::forget(mem::replace(self, Some(f()))) + if let None = self { + *self = Some(f()); } // SAFETY: a `None` variant for `self` would have been replaced by a `Some` @@ -1794,12 +1717,7 @@ impl<T> Option<T> { /// assert_eq!(x.zip(z), None); /// ``` #[stable(feature = "option_zip_option", since = "1.46.0")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn zip<U>(self, other: Option<U>) -> Option<(T, U)> - where - T: ~const Destruct, - U: ~const Destruct, - { + pub fn zip<U>(self, other: Option<U>) -> Option<(T, U)> { match (self, other) { (Some(a), Some(b)) => Some((a, b)), _ => None, @@ -1835,13 +1753,9 @@ impl<T> Option<T> { /// assert_eq!(x.zip_with(None, Point::new), None); /// ``` #[unstable(feature = "option_zip", issue = "70086")] - #[rustc_const_unstable(feature = "const_option_ext", issue = "91930")] - pub const fn zip_with<U, F, R>(self, other: Option<U>, f: F) -> Option<R> + pub fn zip_with<U, F, R>(self, other: Option<U>, f: F) -> Option<R> where - F: ~const FnOnce(T, U) -> R, - F: ~const Destruct, - T: ~const Destruct, - U: ~const Destruct, + F: FnOnce(T, U) -> R, { match (self, other) { (Some(a), Some(b)) => Some(f(a, b)), @@ -1867,12 +1781,7 @@ impl<T, U> Option<(T, U)> { /// ``` #[inline] #[stable(feature = "unzip_option", since = "1.66.0")] - #[rustc_const_unstable(feature = "const_option", issue = "67441")] - pub const fn unzip(self) -> (Option<T>, Option<U>) - where - T: ~const Destruct, - U: ~const Destruct, - { + pub fn unzip(self) -> (Option<T>, Option<U>) { match self { Some((a, b)) => (Some(a), Some(b)), None => (None, None), @@ -1922,10 +1831,9 @@ impl<T> Option<&T> { /// ``` #[must_use = "`self` will be dropped if the result is not used"] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_option_cloned", issue = "91582")] - pub const fn cloned(self) -> Option<T> + pub fn cloned(self) -> Option<T> where - T: ~const Clone, + T: Clone, { match self { Some(t) => Some(t.clone()), @@ -1974,10 +1882,9 @@ impl<T> Option<&mut T> { /// ``` #[must_use = "`self` will be dropped if the result is not used"] #[stable(since = "1.26.0", feature = "option_ref_mut_cloned")] - #[rustc_const_unstable(feature = "const_option_cloned", issue = "91582")] - pub const fn cloned(self) -> Option<T> + pub fn cloned(self) -> Option<T> where - T: ~const Clone, + T: Clone, { match self { Some(t) => Some(t.clone()), @@ -2030,10 +1937,9 @@ const fn expect_failed(msg: &str) -> ! { ///////////////////////////////////////////////////////////////////////////// #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_clone", issue = "91805")] -impl<T> const Clone for Option<T> +impl<T> Clone for Option<T> where - T: ~const Clone + ~const Destruct, + T: Clone, { #[inline] fn clone(&self) -> Self { @@ -2053,8 +1959,7 @@ where } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] -impl<T> const Default for Option<T> { +impl<T> Default for Option<T> { /// Returns [`None`][Option::None]. /// /// # Examples @@ -2114,8 +2019,7 @@ impl<'a, T> IntoIterator for &'a mut Option<T> { } #[stable(since = "1.12.0", feature = "option_from")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T> const From<T> for Option<T> { +impl<T> From<T> for Option<T> { /// Moves `val` into a new [`Some`]. /// /// # Examples @@ -2131,8 +2035,7 @@ impl<T> const From<T> for Option<T> { } #[stable(feature = "option_ref_from_ref_option", since = "1.30.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<'a, T> const From<&'a Option<T>> for Option<&'a T> { +impl<'a, T> From<&'a Option<T>> for Option<&'a T> { /// Converts from `&Option<T>` to `Option<&T>`. /// /// # Examples @@ -2159,8 +2062,7 @@ impl<'a, T> const From<&'a Option<T>> for Option<&'a T> { } #[stable(feature = "option_ref_from_ref_option", since = "1.30.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<'a, T> const From<&'a mut Option<T>> for Option<&'a mut T> { +impl<'a, T> From<&'a mut Option<T>> for Option<&'a mut T> { /// Converts from `&mut Option<T>` to `Option<&mut T>` /// /// # Examples @@ -2507,8 +2409,7 @@ impl<A, V: FromIterator<A>> FromIterator<Option<A>> for Option<V> { } #[unstable(feature = "try_trait_v2", issue = "84277")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T> const ops::Try for Option<T> { +impl<T> ops::Try for Option<T> { type Output = T; type Residual = Option<convert::Infallible>; @@ -2527,8 +2428,7 @@ impl<T> const ops::Try for Option<T> { } #[unstable(feature = "try_trait_v2", issue = "84277")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T> const ops::FromResidual for Option<T> { +impl<T> ops::FromResidual for Option<T> { #[inline] fn from_residual(residual: Option<convert::Infallible>) -> Self { match residual { @@ -2546,8 +2446,7 @@ impl<T> ops::FromResidual<ops::Yeet<()>> for Option<T> { } #[unstable(feature = "try_trait_v2_residual", issue = "91285")] -#[rustc_const_unstable(feature = "const_try", issue = "74935")] -impl<T> const ops::Residual<T> for Option<convert::Infallible> { +impl<T> ops::Residual<T> for Option<convert::Infallible> { type TryType = Option<T>; } diff --git a/library/core/src/panic.rs b/library/core/src/panic.rs index 8338a5d7e..20be60d35 100644 --- a/library/core/src/panic.rs +++ b/library/core/src/panic.rs @@ -28,16 +28,18 @@ pub macro panic_2015 { $crate::panicking::panic($msg) ), // Use `panic_str` instead of `panic_display::<&str>` for non_fmt_panic lint. - ($msg:expr $(,)?) => ( - $crate::panicking::panic_str($msg) - ), + ($msg:expr $(,)?) => ({ + $crate::panicking::panic_str($msg); + }), // Special-case the single-argument case for const_panic. - ("{}", $arg:expr $(,)?) => ( - $crate::panicking::panic_display(&$arg) - ), - ($fmt:expr, $($arg:tt)+) => ( - $crate::panicking::panic_fmt($crate::const_format_args!($fmt, $($arg)+)) - ), + ("{}", $arg:expr $(,)?) => ({ + $crate::panicking::panic_display(&$arg); + }), + ($fmt:expr, $($arg:tt)+) => ({ + // Semicolon to prevent temporaries inside the formatting machinery from + // being considered alive in the caller after the panic_fmt call. + $crate::panicking::panic_fmt($crate::const_format_args!($fmt, $($arg)+)); + }), } #[doc(hidden)] @@ -50,12 +52,14 @@ pub macro panic_2021 { $crate::panicking::panic("explicit panic") ), // Special-case the single-argument case for const_panic. - ("{}", $arg:expr $(,)?) => ( - $crate::panicking::panic_display(&$arg) - ), - ($($t:tt)+) => ( - $crate::panicking::panic_fmt($crate::const_format_args!($($t)+)) - ), + ("{}", $arg:expr $(,)?) => ({ + $crate::panicking::panic_display(&$arg); + }), + ($($t:tt)+) => ({ + // Semicolon to prevent temporaries inside the formatting machinery from + // being considered alive in the caller after the panic_fmt call. + $crate::panicking::panic_fmt($crate::const_format_args!($($t)+)); + }), } #[doc(hidden)] @@ -69,9 +73,9 @@ pub macro unreachable_2015 { ), // Use of `unreachable_display` for non_fmt_panic lint. // NOTE: the message ("internal error ...") is embedded directly in unreachable_display - ($msg:expr $(,)?) => ( - $crate::panicking::unreachable_display(&$msg) - ), + ($msg:expr $(,)?) => ({ + $crate::panicking::unreachable_display(&$msg); + }), ($fmt:expr, $($arg:tt)*) => ( $crate::panic!($crate::concat!("internal error: entered unreachable code: ", $fmt), $($arg)*) ), diff --git a/library/core/src/panic/panic_info.rs b/library/core/src/panic/panic_info.rs index 06fbe083c..5576adde8 100644 --- a/library/core/src/panic/panic_info.rs +++ b/library/core/src/panic/panic_info.rs @@ -134,7 +134,7 @@ impl<'a> PanicInfo<'a> { /// whose ABI does not support unwinding. /// /// It is safe for a panic handler to unwind even when this function returns - /// true, however this will simply cause the panic handler to be called + /// false, however this will simply cause the panic handler to be called /// again. #[must_use] #[unstable(feature = "panic_can_unwind", issue = "92988")] diff --git a/library/core/src/panicking.rs b/library/core/src/panicking.rs index efeb726ab..81be3fb22 100644 --- a/library/core/src/panicking.rs +++ b/library/core/src/panicking.rs @@ -165,7 +165,7 @@ fn panic_bounds_check(index: usize, len: usize) -> ! { #[cold] #[cfg_attr(not(feature = "panic_immediate_abort"), inline(never))] #[track_caller] -#[cfg_attr(not(bootstrap), lang = "panic_misaligned_pointer_dereference")] // needed by codegen for panic on misaligned pointer deref +#[lang = "panic_misaligned_pointer_dereference"] // needed by codegen for panic on misaligned pointer deref fn panic_misaligned_pointer_dereference(required: usize, found: usize) -> ! { if cfg!(feature = "panic_immediate_abort") { super::intrinsics::abort() diff --git a/library/core/src/pin.rs b/library/core/src/pin.rs index c4b89a630..6b319b435 100644 --- a/library/core/src/pin.rs +++ b/library/core/src/pin.rs @@ -393,6 +393,8 @@ use crate::ops::{CoerceUnsized, Deref, DerefMut, DispatchFromDyn, Receiver}; /// value in place, preventing the value referenced by that pointer from being moved /// unless it implements [`Unpin`]. /// +/// `Pin<P>` is guaranteed to have the same memory layout and ABI as `P`. +/// /// *See the [`pin` module] documentation for an explanation of pinning.* /// /// [`pin` module]: self diff --git a/library/core/src/primitive_docs.rs b/library/core/src/primitive_docs.rs index 3df990e5d..8266e8990 100644 --- a/library/core/src/primitive_docs.rs +++ b/library/core/src/primitive_docs.rs @@ -1,8 +1,7 @@ // `library/{std,core}/src/primitive_docs.rs` should have the same contents. // These are different files so that relative links work properly without // having to have `CARGO_PKG_NAME` set, but conceptually they should always be the same. -#[cfg_attr(bootstrap, doc(primitive = "bool"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "bool")] +#[rustc_doc_primitive = "bool"] #[doc(alias = "true")] #[doc(alias = "false")] /// The boolean type. @@ -64,8 +63,7 @@ #[stable(feature = "rust1", since = "1.0.0")] mod prim_bool {} -#[cfg_attr(bootstrap, doc(primitive = "never"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "never")] +#[rustc_doc_primitive = "never"] #[doc(alias = "!")] // /// The `!` type, also called "never". @@ -276,8 +274,7 @@ mod prim_bool {} #[unstable(feature = "never_type", issue = "35121")] mod prim_never {} -#[cfg_attr(bootstrap, doc(primitive = "char"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "char")] +#[rustc_doc_primitive = "char"] #[allow(rustdoc::invalid_rust_codeblocks)] /// A character type. /// @@ -401,8 +398,7 @@ mod prim_never {} #[stable(feature = "rust1", since = "1.0.0")] mod prim_char {} -#[cfg_attr(bootstrap, doc(primitive = "unit"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "unit")] +#[rustc_doc_primitive = "unit"] #[doc(alias = "(")] #[doc(alias = ")")] #[doc(alias = "()")] @@ -464,8 +460,7 @@ impl Copy for () { // empty } -#[cfg_attr(bootstrap, doc(primitive = "pointer"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "pointer")] +#[rustc_doc_primitive = "pointer"] #[doc(alias = "ptr")] #[doc(alias = "*")] #[doc(alias = "*const")] @@ -555,6 +550,7 @@ impl Copy for () { /// /// ``` /// # #![feature(rustc_private)] +/// #[allow(unused_extern_crates)] /// extern crate libc; /// /// use std::mem; @@ -581,8 +577,7 @@ impl Copy for () { #[stable(feature = "rust1", since = "1.0.0")] mod prim_pointer {} -#[cfg_attr(bootstrap, doc(primitive = "array"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "array")] +#[rustc_doc_primitive = "array"] #[doc(alias = "[]")] #[doc(alias = "[T;N]")] // unfortunately, rustdoc doesn't have fuzzy search for aliases #[doc(alias = "[T; N]")] @@ -616,6 +611,9 @@ mod prim_pointer {} /// if the element type allows it. As a stopgap, trait implementations are /// statically generated up to size 32. /// +/// Arrays of sizes from 1 to 12 (inclusive) implement [`From<Tuple>`], where `Tuple` +/// is a homogenous [prim@tuple] of appropriate length. +/// /// Arrays coerce to [slices (`[T]`)][slice], so a slice method may be called on /// an array. Indeed, this provides most of the API for working with arrays. /// @@ -678,6 +676,13 @@ mod prim_pointer {} /// move_away(roa); /// ``` /// +/// Arrays can be created from homogenous tuples of appropriate length: +/// +/// ``` +/// let tuple: (u32, u32, u32) = (1, 2, 3); +/// let array: [u32; 3] = tuple.into(); +/// ``` +/// /// # Editions /// /// Prior to Rust 1.53, arrays did not implement [`IntoIterator`] by value, so the method call @@ -780,11 +785,11 @@ mod prim_pointer {} /// [`Borrow`]: borrow::Borrow /// [`BorrowMut`]: borrow::BorrowMut /// [slice pattern]: ../reference/patterns.html#slice-patterns +/// [`From<Tuple>`]: convert::From #[stable(feature = "rust1", since = "1.0.0")] mod prim_array {} -#[cfg_attr(bootstrap, doc(primitive = "slice"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "slice")] +#[rustc_doc_primitive = "slice"] #[doc(alias = "[")] #[doc(alias = "]")] #[doc(alias = "[]")] @@ -876,8 +881,7 @@ mod prim_array {} #[stable(feature = "rust1", since = "1.0.0")] mod prim_slice {} -#[cfg_attr(bootstrap, doc(primitive = "str"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "str")] +#[rustc_doc_primitive = "str"] /// String slices. /// /// *[See also the `std::str` module](crate::str).* @@ -944,8 +948,7 @@ mod prim_slice {} #[stable(feature = "rust1", since = "1.0.0")] mod prim_str {} -#[cfg_attr(bootstrap, doc(primitive = "tuple"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "tuple")] +#[rustc_doc_primitive = "tuple"] #[doc(alias = "(")] #[doc(alias = ")")] #[doc(alias = "()")] @@ -1009,7 +1012,9 @@ mod prim_str {} /// * [`Debug`] /// * [`Default`] /// * [`Hash`] +/// * [`From<[T; N]>`][from] /// +/// [from]: convert::From /// [`Debug`]: fmt::Debug /// [`Hash`]: hash::Hash /// @@ -1060,6 +1065,13 @@ mod prim_str {} /// assert_eq!(y, 5); /// ``` /// +/// Homogenous tuples can be created from arrays of appropriate length: +/// +/// ``` +/// let array: [u32; 3] = [1, 2, 3]; +/// let tuple: (u32, u32, u32) = array.into(); +/// ``` +/// #[stable(feature = "rust1", since = "1.0.0")] mod prim_tuple {} @@ -1088,8 +1100,7 @@ impl<T: Copy> Copy for (T,) { // empty } -#[cfg_attr(bootstrap, doc(primitive = "f32"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "f32")] +#[rustc_doc_primitive = "f32"] /// A 32-bit floating point type (specifically, the "binary32" type defined in IEEE 754-2008). /// /// This type can represent a wide range of decimal numbers, like `3.5`, `27`, @@ -1155,8 +1166,7 @@ impl<T: Copy> Copy for (T,) { #[stable(feature = "rust1", since = "1.0.0")] mod prim_f32 {} -#[cfg_attr(bootstrap, doc(primitive = "f64"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "f64")] +#[rustc_doc_primitive = "f64"] /// A 64-bit floating point type (specifically, the "binary64" type defined in IEEE 754-2008). /// /// This type is very similar to [`f32`], but has increased @@ -1171,78 +1181,67 @@ mod prim_f32 {} #[stable(feature = "rust1", since = "1.0.0")] mod prim_f64 {} -#[cfg_attr(bootstrap, doc(primitive = "i8"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "i8")] +#[rustc_doc_primitive = "i8"] // /// The 8-bit signed integer type. #[stable(feature = "rust1", since = "1.0.0")] mod prim_i8 {} -#[cfg_attr(bootstrap, doc(primitive = "i16"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "i16")] +#[rustc_doc_primitive = "i16"] // /// The 16-bit signed integer type. #[stable(feature = "rust1", since = "1.0.0")] mod prim_i16 {} -#[cfg_attr(bootstrap, doc(primitive = "i32"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "i32")] +#[rustc_doc_primitive = "i32"] // /// The 32-bit signed integer type. #[stable(feature = "rust1", since = "1.0.0")] mod prim_i32 {} -#[cfg_attr(bootstrap, doc(primitive = "i64"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "i64")] +#[rustc_doc_primitive = "i64"] // /// The 64-bit signed integer type. #[stable(feature = "rust1", since = "1.0.0")] mod prim_i64 {} -#[cfg_attr(bootstrap, doc(primitive = "i128"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "i128")] +#[rustc_doc_primitive = "i128"] // /// The 128-bit signed integer type. #[stable(feature = "i128", since = "1.26.0")] mod prim_i128 {} -#[cfg_attr(bootstrap, doc(primitive = "u8"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "u8")] +#[rustc_doc_primitive = "u8"] // /// The 8-bit unsigned integer type. #[stable(feature = "rust1", since = "1.0.0")] mod prim_u8 {} -#[cfg_attr(bootstrap, doc(primitive = "u16"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "u16")] +#[rustc_doc_primitive = "u16"] // /// The 16-bit unsigned integer type. #[stable(feature = "rust1", since = "1.0.0")] mod prim_u16 {} -#[cfg_attr(bootstrap, doc(primitive = "u32"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "u32")] +#[rustc_doc_primitive = "u32"] // /// The 32-bit unsigned integer type. #[stable(feature = "rust1", since = "1.0.0")] mod prim_u32 {} -#[cfg_attr(bootstrap, doc(primitive = "u64"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "u64")] +#[rustc_doc_primitive = "u64"] // /// The 64-bit unsigned integer type. #[stable(feature = "rust1", since = "1.0.0")] mod prim_u64 {} -#[cfg_attr(bootstrap, doc(primitive = "u128"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "u128")] +#[rustc_doc_primitive = "u128"] // /// The 128-bit unsigned integer type. #[stable(feature = "i128", since = "1.26.0")] mod prim_u128 {} -#[cfg_attr(bootstrap, doc(primitive = "isize"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "isize")] +#[rustc_doc_primitive = "isize"] // /// The pointer-sized signed integer type. /// @@ -1252,8 +1251,7 @@ mod prim_u128 {} #[stable(feature = "rust1", since = "1.0.0")] mod prim_isize {} -#[cfg_attr(bootstrap, doc(primitive = "usize"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "usize")] +#[rustc_doc_primitive = "usize"] // /// The pointer-sized unsigned integer type. /// @@ -1263,8 +1261,7 @@ mod prim_isize {} #[stable(feature = "rust1", since = "1.0.0")] mod prim_usize {} -#[cfg_attr(bootstrap, doc(primitive = "reference"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "reference")] +#[rustc_doc_primitive = "reference"] #[doc(alias = "&")] #[doc(alias = "&mut")] // @@ -1396,8 +1393,7 @@ mod prim_usize {} #[stable(feature = "rust1", since = "1.0.0")] mod prim_ref {} -#[cfg_attr(bootstrap, doc(primitive = "fn"))] -#[cfg_attr(not(bootstrap), rustc_doc_primitive = "fn")] +#[rustc_doc_primitive = "fn"] // /// Function pointers, like `fn(usize) -> bool`. /// diff --git a/library/core/src/ptr/alignment.rs b/library/core/src/ptr/alignment.rs index efe6d4183..bbf7199ff 100644 --- a/library/core/src/ptr/alignment.rs +++ b/library/core/src/ptr/alignment.rs @@ -9,8 +9,7 @@ use crate::{cmp, fmt, hash, mem, num}; /// Note that particularly large alignments, while representable in this type, /// are likely not to be supported by actual allocators and linkers. #[unstable(feature = "ptr_alignment_type", issue = "102070")] -#[derive(Copy, Clone, Eq)] -#[derive_const(PartialEq)] +#[derive(Copy, Clone, PartialEq, Eq)] #[repr(transparent)] pub struct Alignment(AlignmentEnum); @@ -170,7 +169,7 @@ impl From<Alignment> for usize { #[rustc_const_unstable(feature = "const_alloc_layout", issue = "67521")] #[unstable(feature = "ptr_alignment_type", issue = "102070")] -impl const cmp::Ord for Alignment { +impl cmp::Ord for Alignment { #[inline] fn cmp(&self, other: &Self) -> cmp::Ordering { self.as_nonzero().get().cmp(&other.as_nonzero().get()) @@ -179,7 +178,7 @@ impl const cmp::Ord for Alignment { #[rustc_const_unstable(feature = "const_alloc_layout", issue = "67521")] #[unstable(feature = "ptr_alignment_type", issue = "102070")] -impl const cmp::PartialOrd for Alignment { +impl cmp::PartialOrd for Alignment { #[inline] fn partial_cmp(&self, other: &Self) -> Option<cmp::Ordering> { Some(self.cmp(other)) @@ -201,8 +200,7 @@ type AlignmentEnum = AlignmentEnum32; #[cfg(target_pointer_width = "64")] type AlignmentEnum = AlignmentEnum64; -#[derive(Copy, Clone, Eq)] -#[derive_const(PartialEq)] +#[derive(Copy, Clone, PartialEq, Eq)] #[repr(u16)] enum AlignmentEnum16 { _Align1Shl0 = 1 << 0, @@ -223,8 +221,7 @@ enum AlignmentEnum16 { _Align1Shl15 = 1 << 15, } -#[derive(Copy, Clone, Eq)] -#[derive_const(PartialEq)] +#[derive(Copy, Clone, PartialEq, Eq)] #[repr(u32)] enum AlignmentEnum32 { _Align1Shl0 = 1 << 0, @@ -261,8 +258,7 @@ enum AlignmentEnum32 { _Align1Shl31 = 1 << 31, } -#[derive(Copy, Clone, Eq)] -#[derive_const(PartialEq)] +#[derive(Copy, Clone, PartialEq, Eq)] #[repr(u64)] enum AlignmentEnum64 { _Align1Shl0 = 1 << 0, diff --git a/library/core/src/ptr/const_ptr.rs b/library/core/src/ptr/const_ptr.rs index 839afc57f..6e1e862d3 100644 --- a/library/core/src/ptr/const_ptr.rs +++ b/library/core/src/ptr/const_ptr.rs @@ -132,8 +132,8 @@ impl<T: ?Sized> *const T { /// ``` #[unstable(feature = "ptr_to_from_bits", issue = "91126")] #[deprecated( - since = "1.67", - note = "replaced by the `exposed_addr` method, or update your code \ + since = "1.67.0", + note = "replaced by the `expose_addr` method, or update your code \ to follow the strict provenance rules using its APIs" )] #[inline(always)] @@ -161,7 +161,7 @@ impl<T: ?Sized> *const T { /// ``` #[unstable(feature = "ptr_to_from_bits", issue = "91126")] #[deprecated( - since = "1.67", + since = "1.67.0", note = "replaced by the `ptr::from_exposed_addr` function, or update \ your code to follow the strict provenance rules using its APIs" )] @@ -264,7 +264,7 @@ impl<T: ?Sized> *const T { let dest_addr = addr as isize; let offset = dest_addr.wrapping_sub(self_addr); - // This is the canonical desugarring of this operation + // This is the canonical desugaring of this operation self.wrapping_byte_offset(offset) } @@ -916,8 +916,16 @@ impl<T: ?Sized> *const T { where T: Sized, { + #[cfg(bootstrap)] // SAFETY: the caller must uphold the safety contract for `offset`. - unsafe { self.offset(count as isize) } + unsafe { + self.offset(count as isize) + } + #[cfg(not(bootstrap))] + // SAFETY: the caller must uphold the safety contract for `offset`. + unsafe { + intrinsics::offset(self, count) + } } /// Calculates the offset from a pointer in bytes (convenience for `.byte_offset(count as isize)`). @@ -1187,7 +1195,7 @@ impl<T: ?Sized> *const T { /// /// [`ptr::read`]: crate::ptr::read() #[stable(feature = "pointer_methods", since = "1.26.0")] - #[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")] + #[rustc_const_stable(feature = "const_ptr_read", since = "1.71.0")] #[inline] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces pub const unsafe fn read(self) -> T @@ -1228,7 +1236,7 @@ impl<T: ?Sized> *const T { /// /// [`ptr::read_unaligned`]: crate::ptr::read_unaligned() #[stable(feature = "pointer_methods", since = "1.26.0")] - #[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")] + #[rustc_const_stable(feature = "const_ptr_read", since = "1.71.0")] #[inline] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces pub const unsafe fn read_unaligned(self) -> T @@ -1650,11 +1658,10 @@ impl<T> *const [T] { /// } /// ``` #[unstable(feature = "slice_ptr_get", issue = "74265")] - #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] #[inline] - pub const unsafe fn get_unchecked<I>(self, index: I) -> *const I::Output + pub unsafe fn get_unchecked<I>(self, index: I) -> *const I::Output where - I: ~const SliceIndex<[T]>, + I: SliceIndex<[T]>, { // SAFETY: the caller ensures that `self` is dereferenceable and `index` in-bounds. unsafe { index.get_unchecked(self) } diff --git a/library/core/src/ptr/mod.rs b/library/core/src/ptr/mod.rs index 818f1a919..d0cb2f715 100644 --- a/library/core/src/ptr/mod.rs +++ b/library/core/src/ptr/mod.rs @@ -374,6 +374,7 @@ use crate::hash; use crate::intrinsics::{ self, assert_unsafe_precondition, is_aligned_and_not_null, is_nonoverlapping, }; +use crate::marker::FnPtr; use crate::mem::{self, MaybeUninit}; @@ -440,10 +441,18 @@ mod mut_ptr; /// /// * `to_drop` must be [valid] for both reads and writes. /// -/// * `to_drop` must be properly aligned. +/// * `to_drop` must be properly aligned, even if `T` has size 0. /// -/// * The value `to_drop` points to must be valid for dropping, which may mean it must uphold -/// additional invariants - this is type-dependent. +/// * `to_drop` must be nonnull, even if `T` has size 0. +/// +/// * The value `to_drop` points to must be valid for dropping, which may mean +/// it must uphold additional invariants. These invariants depend on the type +/// of the value being dropped. For instance, when dropping a Box, the box's +/// pointer to the heap must be valid. +/// +/// * While `drop_in_place` is executing, the only way to access parts of +/// `to_drop` is through the `&mut self` references supplied to the +/// `Drop::drop` methods that `drop_in_place` invokes. /// /// Additionally, if `T` is not [`Copy`], using the pointed-to value after /// calling `drop_in_place` can cause undefined behavior. Note that `*to_drop = @@ -451,8 +460,6 @@ mod mut_ptr; /// again. [`write()`] can be used to overwrite data without causing it to be /// dropped. /// -/// Note that even if `T` has size `0`, the pointer must be non-null and properly aligned. -/// /// [valid]: self#safety /// /// # Examples @@ -1132,7 +1139,8 @@ pub const unsafe fn replace<T>(dst: *mut T, mut src: T) -> T { /// [valid]: self#safety #[inline] #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")] +#[rustc_const_stable(feature = "const_ptr_read", since = "1.71.0")] +#[rustc_allow_const_fn_unstable(const_mut_refs, const_maybe_uninit_as_mut_ptr)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces pub const unsafe fn read<T>(src: *const T) -> T { // It would be semantically correct to implement this via `copy_nonoverlapping` @@ -1167,26 +1175,7 @@ pub const unsafe fn read<T>(src: *const T) -> T { "ptr::read requires that the pointer argument is aligned and non-null", [T](src: *const T) => is_aligned_and_not_null(src) ); - - #[cfg(bootstrap)] - { - // We are calling the intrinsics directly to avoid function calls in the - // generated code as `intrinsics::copy_nonoverlapping` is a wrapper function. - extern "rust-intrinsic" { - #[rustc_const_stable(feature = "const_intrinsic_copy", since = "1.63.0")] - fn copy_nonoverlapping<T>(src: *const T, dst: *mut T, count: usize); - } - - // `src` cannot overlap `tmp` because `tmp` was just allocated on - // the stack as a separate allocated object. - let mut tmp = MaybeUninit::<T>::uninit(); - copy_nonoverlapping(src, tmp.as_mut_ptr(), 1); - tmp.assume_init() - } - #[cfg(not(bootstrap))] - { - crate::intrinsics::read_via_copy(src) - } + crate::intrinsics::read_via_copy(src) } } @@ -1267,7 +1256,8 @@ pub const unsafe fn read<T>(src: *const T) -> T { /// ``` #[inline] #[stable(feature = "ptr_unaligned", since = "1.17.0")] -#[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")] +#[rustc_const_stable(feature = "const_ptr_read", since = "1.71.0")] +#[rustc_allow_const_fn_unstable(const_mut_refs, const_maybe_uninit_as_mut_ptr)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces pub const unsafe fn read_unaligned<T>(src: *const T) -> T { let mut tmp = MaybeUninit::<T>::uninit(); @@ -1367,13 +1357,13 @@ pub const unsafe fn read_unaligned<T>(src: *const T) -> T { #[rustc_const_unstable(feature = "const_ptr_write", issue = "86302")] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces pub const unsafe fn write<T>(dst: *mut T, src: T) { - // We are calling the intrinsics directly to avoid function calls in the generated code - // as `intrinsics::copy_nonoverlapping` is a wrapper function. - extern "rust-intrinsic" { - #[rustc_const_stable(feature = "const_intrinsic_copy", since = "1.63.0")] - #[rustc_nounwind] - fn copy_nonoverlapping<T>(src: *const T, dst: *mut T, count: usize); - } + // Semantically, it would be fine for this to be implemented as a + // `copy_nonoverlapping` and appropriate drop suppression of `src`. + + // However, implementing via that currently produces more MIR than is ideal. + // Using an intrinsic keeps it down to just the simple `*dst = move src` in + // MIR (11 statements shorter, at the time of writing), and also allows + // `src` to stay an SSA value in codegen_ssa, rather than a memory one. // SAFETY: the caller must guarantee that `dst` is valid for writes. // `dst` cannot overlap `src` because the caller has mutable access @@ -1383,8 +1373,7 @@ pub const unsafe fn write<T>(dst: *mut T, src: T) { "ptr::write requires that the pointer argument is aligned and non-null", [T](dst: *mut T) => is_aligned_and_not_null(dst) ); - copy_nonoverlapping(&src as *const T, dst, 1); - intrinsics::forget(src); + intrinsics::write_via_move(dst, src) } } @@ -1651,8 +1640,8 @@ pub(crate) const unsafe fn align_offset<T: Sized>(p: *const T, a: usize) -> usiz // FIXME(#75598): Direct use of these intrinsics improves codegen significantly at opt-level <= // 1, where the method versions of these operations are not inlined. use intrinsics::{ - cttz_nonzero, exact_div, mul_with_overflow, unchecked_rem, unchecked_shl, unchecked_shr, - unchecked_sub, wrapping_add, wrapping_mul, wrapping_sub, + assume, cttz_nonzero, exact_div, mul_with_overflow, unchecked_rem, unchecked_shl, + unchecked_shr, unchecked_sub, wrapping_add, wrapping_mul, wrapping_sub, }; /// Calculate multiplicative modular inverse of `x` modulo `m`. @@ -1743,12 +1732,18 @@ pub(crate) const unsafe fn align_offset<T: Sized>(p: *const T, a: usize) -> usiz // in a branch-free way and then bitwise-OR it with whatever result the `-p mod a` // computation produces. + let aligned_address = wrapping_add(addr, a_minus_one) & wrapping_sub(0, a); + let byte_offset = wrapping_sub(aligned_address, addr); + // FIXME: Remove the assume after <https://github.com/llvm/llvm-project/issues/62502> + // SAFETY: Masking by `-a` can only affect the low bits, and thus cannot have reduced + // the value by more than `a-1`, so even though the intermediate values might have + // wrapped, the byte_offset is always in `[0, a)`. + unsafe { assume(byte_offset < a) }; + // SAFETY: `stride == 0` case has been handled by the special case above. let addr_mod_stride = unsafe { unchecked_rem(addr, stride) }; return if addr_mod_stride == 0 { - let aligned_address = wrapping_add(addr, a_minus_one) & wrapping_sub(0, a); - let byte_offset = wrapping_sub(aligned_address, addr); // SAFETY: `stride` is non-zero. This is guaranteed to divide exactly as well, because // addr has been verified to be aligned to the original type’s alignment requirements. unsafe { exact_div(byte_offset, stride) } @@ -1764,7 +1759,12 @@ pub(crate) const unsafe fn align_offset<T: Sized>(p: *const T, a: usize) -> usiz // miracles, given the situations this case has to deal with. // SAFETY: a is power-of-two hence non-zero. stride == 0 case is handled above. - let gcdpow = unsafe { cttz_nonzero(stride).min(cttz_nonzero(a)) }; + // FIXME(const-hack) replace with min + let gcdpow = unsafe { + let x = cttz_nonzero(stride); + let y = cttz_nonzero(a); + if x < y { x } else { y } + }; // SAFETY: gcdpow has an upper-bound that’s at most the number of bits in a usize. let gcd = unsafe { unchecked_shl(1usize, gcdpow) }; // SAFETY: gcd is always greater or equal to 1. @@ -1892,205 +1892,52 @@ pub fn hash<T: ?Sized, S: hash::Hasher>(hashee: *const T, into: &mut S) { hashee.hash(into); } -#[cfg(bootstrap)] -mod old_fn_ptr_impl { - use super::*; - // If this is a unary fn pointer, it adds a doc comment. - // Otherwise, it hides the docs entirely. - macro_rules! maybe_fnptr_doc { - (@ #[$meta:meta] $item:item) => { - #[doc(hidden)] - #[$meta] - $item - }; - ($a:ident @ #[$meta:meta] $item:item) => { - #[doc(fake_variadic)] - #[doc = "This trait is implemented for function pointers with up to twelve arguments."] - #[$meta] - $item - }; - ($a:ident $($rest_a:ident)+ @ #[$meta:meta] $item:item) => { - #[doc(hidden)] - #[$meta] - $item - }; - } - - // FIXME(strict_provenance_magic): function pointers have buggy codegen that - // necessitates casting to a usize to get the backend to do the right thing. - // for now I will break AVR to silence *a billion* lints. We should probably - // have a proper "opaque function pointer type" to handle this kind of thing. - - // Impls for function pointers - macro_rules! fnptr_impls_safety_abi { - ($FnTy: ty, $($Arg: ident),*) => { - fnptr_impls_safety_abi! { #[stable(feature = "fnptr_impls", since = "1.4.0")] $FnTy, $($Arg),* } - }; - (@c_unwind $FnTy: ty, $($Arg: ident),*) => { - fnptr_impls_safety_abi! { #[unstable(feature = "c_unwind", issue = "74990")] $FnTy, $($Arg),* } - }; - (#[$meta:meta] $FnTy: ty, $($Arg: ident),*) => { - maybe_fnptr_doc! { - $($Arg)* @ - #[$meta] - impl<Ret, $($Arg),*> PartialEq for $FnTy { - #[inline] - fn eq(&self, other: &Self) -> bool { - *self as usize == *other as usize - } - } - } - - maybe_fnptr_doc! { - $($Arg)* @ - #[$meta] - impl<Ret, $($Arg),*> Eq for $FnTy {} - } - - maybe_fnptr_doc! { - $($Arg)* @ - #[$meta] - impl<Ret, $($Arg),*> PartialOrd for $FnTy { - #[inline] - fn partial_cmp(&self, other: &Self) -> Option<Ordering> { - (*self as usize).partial_cmp(&(*other as usize)) - } - } - } - - maybe_fnptr_doc! { - $($Arg)* @ - #[$meta] - impl<Ret, $($Arg),*> Ord for $FnTy { - #[inline] - fn cmp(&self, other: &Self) -> Ordering { - (*self as usize).cmp(&(*other as usize)) - } - } - } - - maybe_fnptr_doc! { - $($Arg)* @ - #[$meta] - impl<Ret, $($Arg),*> hash::Hash for $FnTy { - fn hash<HH: hash::Hasher>(&self, state: &mut HH) { - state.write_usize(*self as usize) - } - } - } - - maybe_fnptr_doc! { - $($Arg)* @ - #[$meta] - impl<Ret, $($Arg),*> fmt::Pointer for $FnTy { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - fmt::pointer_fmt_inner(*self as usize, f) - } - } - } - - maybe_fnptr_doc! { - $($Arg)* @ - #[$meta] - impl<Ret, $($Arg),*> fmt::Debug for $FnTy { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - fmt::pointer_fmt_inner(*self as usize, f) - } - } - } - } - } - - macro_rules! fnptr_impls_args { - ($($Arg: ident),+) => { - fnptr_impls_safety_abi! { extern "Rust" fn($($Arg),+) -> Ret, $($Arg),+ } - fnptr_impls_safety_abi! { extern "C" fn($($Arg),+) -> Ret, $($Arg),+ } - fnptr_impls_safety_abi! { extern "C" fn($($Arg),+ , ...) -> Ret, $($Arg),+ } - fnptr_impls_safety_abi! { @c_unwind extern "C-unwind" fn($($Arg),+) -> Ret, $($Arg),+ } - fnptr_impls_safety_abi! { @c_unwind extern "C-unwind" fn($($Arg),+ , ...) -> Ret, $($Arg),+ } - fnptr_impls_safety_abi! { unsafe extern "Rust" fn($($Arg),+) -> Ret, $($Arg),+ } - fnptr_impls_safety_abi! { unsafe extern "C" fn($($Arg),+) -> Ret, $($Arg),+ } - fnptr_impls_safety_abi! { unsafe extern "C" fn($($Arg),+ , ...) -> Ret, $($Arg),+ } - fnptr_impls_safety_abi! { @c_unwind unsafe extern "C-unwind" fn($($Arg),+) -> Ret, $($Arg),+ } - fnptr_impls_safety_abi! { @c_unwind unsafe extern "C-unwind" fn($($Arg),+ , ...) -> Ret, $($Arg),+ } - }; - () => { - // No variadic functions with 0 parameters - fnptr_impls_safety_abi! { extern "Rust" fn() -> Ret, } - fnptr_impls_safety_abi! { extern "C" fn() -> Ret, } - fnptr_impls_safety_abi! { @c_unwind extern "C-unwind" fn() -> Ret, } - fnptr_impls_safety_abi! { unsafe extern "Rust" fn() -> Ret, } - fnptr_impls_safety_abi! { unsafe extern "C" fn() -> Ret, } - fnptr_impls_safety_abi! { @c_unwind unsafe extern "C-unwind" fn() -> Ret, } - }; +#[stable(feature = "fnptr_impls", since = "1.4.0")] +impl<F: FnPtr> PartialEq for F { + #[inline] + fn eq(&self, other: &Self) -> bool { + self.addr() == other.addr() } - - fnptr_impls_args! {} - fnptr_impls_args! { T } - fnptr_impls_args! { A, B } - fnptr_impls_args! { A, B, C } - fnptr_impls_args! { A, B, C, D } - fnptr_impls_args! { A, B, C, D, E } - fnptr_impls_args! { A, B, C, D, E, F } - fnptr_impls_args! { A, B, C, D, E, F, G } - fnptr_impls_args! { A, B, C, D, E, F, G, H } - fnptr_impls_args! { A, B, C, D, E, F, G, H, I } - fnptr_impls_args! { A, B, C, D, E, F, G, H, I, J } - fnptr_impls_args! { A, B, C, D, E, F, G, H, I, J, K } - fnptr_impls_args! { A, B, C, D, E, F, G, H, I, J, K, L } } +#[stable(feature = "fnptr_impls", since = "1.4.0")] +impl<F: FnPtr> Eq for F {} -#[cfg(not(bootstrap))] -mod new_fn_ptr_impl { - use super::*; - use crate::marker::FnPtr; - - #[stable(feature = "fnptr_impls", since = "1.4.0")] - impl<F: FnPtr> PartialEq for F { - #[inline] - fn eq(&self, other: &Self) -> bool { - self.addr() == other.addr() - } - } - #[stable(feature = "fnptr_impls", since = "1.4.0")] - impl<F: FnPtr> Eq for F {} - - #[stable(feature = "fnptr_impls", since = "1.4.0")] - impl<F: FnPtr> PartialOrd for F { - #[inline] - fn partial_cmp(&self, other: &Self) -> Option<Ordering> { - self.addr().partial_cmp(&other.addr()) - } +#[stable(feature = "fnptr_impls", since = "1.4.0")] +impl<F: FnPtr> PartialOrd for F { + #[inline] + fn partial_cmp(&self, other: &Self) -> Option<Ordering> { + self.addr().partial_cmp(&other.addr()) } - #[stable(feature = "fnptr_impls", since = "1.4.0")] - impl<F: FnPtr> Ord for F { - #[inline] - fn cmp(&self, other: &Self) -> Ordering { - self.addr().cmp(&other.addr()) - } +} +#[stable(feature = "fnptr_impls", since = "1.4.0")] +impl<F: FnPtr> Ord for F { + #[inline] + fn cmp(&self, other: &Self) -> Ordering { + self.addr().cmp(&other.addr()) } +} - #[stable(feature = "fnptr_impls", since = "1.4.0")] - impl<F: FnPtr> hash::Hash for F { - fn hash<HH: hash::Hasher>(&self, state: &mut HH) { - state.write_usize(self.addr() as _) - } +#[stable(feature = "fnptr_impls", since = "1.4.0")] +impl<F: FnPtr> hash::Hash for F { + fn hash<HH: hash::Hasher>(&self, state: &mut HH) { + state.write_usize(self.addr() as _) } +} - #[stable(feature = "fnptr_impls", since = "1.4.0")] - impl<F: FnPtr> fmt::Pointer for F { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - fmt::pointer_fmt_inner(self.addr() as _, f) - } +#[stable(feature = "fnptr_impls", since = "1.4.0")] +impl<F: FnPtr> fmt::Pointer for F { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + fmt::pointer_fmt_inner(self.addr() as _, f) } +} - #[stable(feature = "fnptr_impls", since = "1.4.0")] - impl<F: FnPtr> fmt::Debug for F { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - fmt::pointer_fmt_inner(self.addr() as _, f) - } +#[stable(feature = "fnptr_impls", since = "1.4.0")] +impl<F: FnPtr> fmt::Debug for F { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + fmt::pointer_fmt_inner(self.addr() as _, f) } } + /// Create a `const` raw pointer to a place, without creating an intermediate reference. /// /// Creating a reference with `&`/`&mut` is only allowed if the pointer is properly aligned @@ -2121,7 +1968,7 @@ mod new_fn_ptr_impl { /// assert_eq!(unsafe { raw_f2.read_unaligned() }, 2); /// ``` /// -/// See [`addr_of_mut`] for how to create a pointer to unininitialized data. +/// See [`addr_of_mut`] for how to create a pointer to uninitialized data. /// Doing that with `addr_of` would not make much sense since one could only /// read the data, and that would be Undefined Behavior. #[stable(feature = "raw_ref_macros", since = "1.51.0")] diff --git a/library/core/src/ptr/mut_ptr.rs b/library/core/src/ptr/mut_ptr.rs index ece5244e9..2fe5164c3 100644 --- a/library/core/src/ptr/mut_ptr.rs +++ b/library/core/src/ptr/mut_ptr.rs @@ -138,8 +138,8 @@ impl<T: ?Sized> *mut T { /// ``` #[unstable(feature = "ptr_to_from_bits", issue = "91126")] #[deprecated( - since = "1.67", - note = "replaced by the `exposed_addr` method, or update your code \ + since = "1.67.0", + note = "replaced by the `expose_addr` method, or update your code \ to follow the strict provenance rules using its APIs" )] #[inline(always)] @@ -167,7 +167,7 @@ impl<T: ?Sized> *mut T { /// ``` #[unstable(feature = "ptr_to_from_bits", issue = "91126")] #[deprecated( - since = "1.67", + since = "1.67.0", note = "replaced by the `ptr::from_exposed_addr_mut` function, or \ update your code to follow the strict provenance rules using its APIs" )] @@ -270,7 +270,7 @@ impl<T: ?Sized> *mut T { let dest_addr = addr as isize; let offset = dest_addr.wrapping_sub(self_addr); - // This is the canonical desugarring of this operation + // This is the canonical desugaring of this operation self.wrapping_byte_offset(offset) } @@ -473,10 +473,20 @@ impl<T: ?Sized> *mut T { where T: Sized, { + #[cfg(bootstrap)] // SAFETY: the caller must uphold the safety contract for `offset`. // The obtained pointer is valid for writes since the caller must // guarantee that it points to the same allocated object as `self`. - unsafe { intrinsics::offset(self, count) as *mut T } + unsafe { + intrinsics::offset(self, count) as *mut T + } + #[cfg(not(bootstrap))] + // SAFETY: the caller must uphold the safety contract for `offset`. + // The obtained pointer is valid for writes since the caller must + // guarantee that it points to the same allocated object as `self`. + unsafe { + intrinsics::offset(self, count) + } } /// Calculates the offset from a pointer in bytes. @@ -1016,8 +1026,16 @@ impl<T: ?Sized> *mut T { where T: Sized, { + #[cfg(bootstrap)] + // SAFETY: the caller must uphold the safety contract for `offset`. + unsafe { + self.offset(count as isize) + } + #[cfg(not(bootstrap))] // SAFETY: the caller must uphold the safety contract for `offset`. - unsafe { self.offset(count as isize) } + unsafe { + intrinsics::offset(self, count) + } } /// Calculates the offset from a pointer in bytes (convenience for `.byte_offset(count as isize)`). @@ -1287,7 +1305,7 @@ impl<T: ?Sized> *mut T { /// /// [`ptr::read`]: crate::ptr::read() #[stable(feature = "pointer_methods", since = "1.26.0")] - #[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")] + #[rustc_const_stable(feature = "const_ptr_read", since = "1.71.0")] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces pub const unsafe fn read(self) -> T @@ -1328,7 +1346,7 @@ impl<T: ?Sized> *mut T { /// /// [`ptr::read_unaligned`]: crate::ptr::read_unaligned() #[stable(feature = "pointer_methods", since = "1.26.0")] - #[rustc_const_unstable(feature = "const_ptr_read", issue = "80377")] + #[rustc_const_stable(feature = "const_ptr_read", since = "1.71.0")] #[inline(always)] #[cfg_attr(miri, track_caller)] // even without panics, this helps for Miri backtraces pub const unsafe fn read_unaligned(self) -> T @@ -2036,11 +2054,10 @@ impl<T> *mut [T] { /// } /// ``` #[unstable(feature = "slice_ptr_get", issue = "74265")] - #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] #[inline(always)] - pub const unsafe fn get_unchecked_mut<I>(self, index: I) -> *mut I::Output + pub unsafe fn get_unchecked_mut<I>(self, index: I) -> *mut I::Output where - I: ~const SliceIndex<[T]>, + I: SliceIndex<[T]>, { // SAFETY: the caller ensures that `self` is dereferenceable and `index` in-bounds. unsafe { index.get_unchecked_mut(self) } diff --git a/library/core/src/ptr/non_null.rs b/library/core/src/ptr/non_null.rs index 13f56c0ce..b492d2f07 100644 --- a/library/core/src/ptr/non_null.rs +++ b/library/core/src/ptr/non_null.rs @@ -449,6 +449,19 @@ impl<T: ?Sized> NonNull<T> { // SAFETY: `self` is a `NonNull` pointer which is necessarily non-null unsafe { NonNull::new_unchecked(self.as_ptr() as *mut U) } } + + /// See [`pointer::add`] for semantics and safety requirements. + #[inline] + pub(crate) const unsafe fn add(self, delta: usize) -> Self + where + T: Sized, + { + // SAFETY: We require that the delta stays in-bounds of the object, and + // thus it cannot become null, as that would require wrapping the + // address space, which no legal objects are allowed to do. + // And the caller promised the `delta` is sound to add. + unsafe { NonNull { pointer: self.pointer.add(delta) } } + } } impl<T> NonNull<[T]> { @@ -676,11 +689,10 @@ impl<T> NonNull<[T]> { /// } /// ``` #[unstable(feature = "slice_ptr_get", issue = "74265")] - #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] #[inline] - pub const unsafe fn get_unchecked_mut<I>(self, index: I) -> NonNull<I::Output> + pub unsafe fn get_unchecked_mut<I>(self, index: I) -> NonNull<I::Output> where - I: ~const SliceIndex<[T]>, + I: SliceIndex<[T]>, { // SAFETY: the caller ensures that `self` is dereferenceable and `index` in-bounds. // As a consequence, the resulting pointer cannot be null. @@ -689,8 +701,7 @@ impl<T> NonNull<[T]> { } #[stable(feature = "nonnull", since = "1.25.0")] -#[rustc_const_unstable(feature = "const_clone", issue = "91805")] -impl<T: ?Sized> const Clone for NonNull<T> { +impl<T: ?Sized> Clone for NonNull<T> { #[inline(always)] fn clone(&self) -> Self { *self @@ -756,8 +767,7 @@ impl<T: ?Sized> hash::Hash for NonNull<T> { } #[unstable(feature = "ptr_internals", issue = "none")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T: ?Sized> const From<Unique<T>> for NonNull<T> { +impl<T: ?Sized> From<Unique<T>> for NonNull<T> { #[inline] fn from(unique: Unique<T>) -> Self { // SAFETY: A Unique pointer cannot be null, so the conditions for @@ -767,8 +777,7 @@ impl<T: ?Sized> const From<Unique<T>> for NonNull<T> { } #[stable(feature = "nonnull", since = "1.25.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T: ?Sized> const From<&mut T> for NonNull<T> { +impl<T: ?Sized> From<&mut T> for NonNull<T> { /// Converts a `&mut T` to a `NonNull<T>`. /// /// This conversion is safe and infallible since references cannot be null. @@ -780,8 +789,7 @@ impl<T: ?Sized> const From<&mut T> for NonNull<T> { } #[stable(feature = "nonnull", since = "1.25.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T: ?Sized> const From<&T> for NonNull<T> { +impl<T: ?Sized> From<&T> for NonNull<T> { /// Converts a `&T` to a `NonNull<T>`. /// /// This conversion is safe and infallible since references cannot be null. diff --git a/library/core/src/ptr/unique.rs b/library/core/src/ptr/unique.rs index 64616142b..a853f15ed 100644 --- a/library/core/src/ptr/unique.rs +++ b/library/core/src/ptr/unique.rs @@ -70,7 +70,8 @@ impl<T: Sized> Unique<T> { #[must_use] #[inline] pub const fn dangling() -> Self { - Self::from(NonNull::dangling()) + // FIXME(const-hack) replace with `From` + Unique { pointer: NonNull::dangling(), _marker: PhantomData } } } @@ -134,13 +135,14 @@ impl<T: ?Sized> Unique<T> { #[must_use = "`self` will be dropped if the result is not used"] #[inline] pub const fn cast<U>(self) -> Unique<U> { - Unique::from(self.pointer.cast()) + // FIXME(const-hack): replace with `From` + // SAFETY: is `NonNull` + unsafe { Unique::new_unchecked(self.pointer.cast().as_ptr()) } } } #[unstable(feature = "ptr_internals", issue = "none")] -#[rustc_const_unstable(feature = "const_clone", issue = "91805")] -impl<T: ?Sized> const Clone for Unique<T> { +impl<T: ?Sized> Clone for Unique<T> { #[inline] fn clone(&self) -> Self { *self @@ -171,7 +173,7 @@ impl<T: ?Sized> fmt::Pointer for Unique<T> { } #[unstable(feature = "ptr_internals", issue = "none")] -impl<T: ?Sized> const From<&mut T> for Unique<T> { +impl<T: ?Sized> From<&mut T> for Unique<T> { /// Converts a `&mut T` to a `Unique<T>`. /// /// This conversion is infallible since references cannot be null. @@ -182,7 +184,7 @@ impl<T: ?Sized> const From<&mut T> for Unique<T> { } #[unstable(feature = "ptr_internals", issue = "none")] -impl<T: ?Sized> const From<NonNull<T>> for Unique<T> { +impl<T: ?Sized> From<NonNull<T>> for Unique<T> { /// Converts a `NonNull<T>` to a `Unique<T>`. /// /// This conversion is infallible since `NonNull` cannot be null. diff --git a/library/core/src/result.rs b/library/core/src/result.rs index c48230fb8..1ee270f4c 100644 --- a/library/core/src/result.rs +++ b/library/core/src/result.rs @@ -489,7 +489,6 @@ #![stable(feature = "rust1", since = "1.0.0")] use crate::iter::{self, FromIterator, FusedIterator, TrustedLen}; -use crate::marker::Destruct; use crate::ops::{self, ControlFlow, Deref, DerefMut}; use crate::{convert, fmt, hint}; @@ -629,16 +628,10 @@ impl<T, E> Result<T, E> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_result_drop", issue = "92384")] - pub const fn ok(self) -> Option<T> - where - E: ~const Destruct, - { + pub fn ok(self) -> Option<T> { match self { Ok(x) => Some(x), - // FIXME: ~const Drop doesn't quite work right yet - #[allow(unused_variables)] - Err(x) => None, + Err(_) => None, } } @@ -658,15 +651,9 @@ impl<T, E> Result<T, E> { /// ``` #[inline] #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_result_drop", issue = "92384")] - pub const fn err(self) -> Option<E> - where - T: ~const Destruct, - { + pub fn err(self) -> Option<E> { match self { - // FIXME: ~const Drop doesn't quite work right yet - #[allow(unused_variables)] - Ok(x) => None, + Ok(_) => None, Err(x) => Some(x), } } @@ -1287,18 +1274,10 @@ impl<T, E> Result<T, E> { /// assert_eq!(x.and(y), Ok("different result type")); /// ``` #[inline] - #[rustc_const_unstable(feature = "const_result_drop", issue = "92384")] #[stable(feature = "rust1", since = "1.0.0")] - pub const fn and<U>(self, res: Result<U, E>) -> Result<U, E> - where - T: ~const Destruct, - U: ~const Destruct, - E: ~const Destruct, - { + pub fn and<U>(self, res: Result<U, E>) -> Result<U, E> { match self { - // FIXME: ~const Drop doesn't quite work right yet - #[allow(unused_variables)] - Ok(x) => res, + Ok(_) => res, Err(e) => Err(e), } } @@ -1370,19 +1349,11 @@ impl<T, E> Result<T, E> { /// assert_eq!(x.or(y), Ok(2)); /// ``` #[inline] - #[rustc_const_unstable(feature = "const_result_drop", issue = "92384")] #[stable(feature = "rust1", since = "1.0.0")] - pub const fn or<F>(self, res: Result<T, F>) -> Result<T, F> - where - T: ~const Destruct, - E: ~const Destruct, - F: ~const Destruct, - { + pub fn or<F>(self, res: Result<T, F>) -> Result<T, F> { match self { Ok(v) => Ok(v), - // FIXME: ~const Drop doesn't quite work right yet - #[allow(unused_variables)] - Err(e) => res, + Err(_) => res, } } @@ -1430,18 +1401,11 @@ impl<T, E> Result<T, E> { /// assert_eq!(x.unwrap_or(default), default); /// ``` #[inline] - #[rustc_const_unstable(feature = "const_result_drop", issue = "92384")] #[stable(feature = "rust1", since = "1.0.0")] - pub const fn unwrap_or(self, default: T) -> T - where - T: ~const Destruct, - E: ~const Destruct, - { + pub fn unwrap_or(self, default: T) -> T { match self { Ok(t) => t, - // FIXME: ~const Drop doesn't quite work right yet - #[allow(unused_variables)] - Err(e) => default, + Err(_) => default, } } @@ -1704,11 +1668,10 @@ fn unwrap_failed<T>(_msg: &str, _error: &T) -> ! { ///////////////////////////////////////////////////////////////////////////// #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_clone", issue = "91805")] -impl<T, E> const Clone for Result<T, E> +impl<T, E> Clone for Result<T, E> where - T: ~const Clone + ~const Destruct, - E: ~const Clone + ~const Destruct, + T: Clone, + E: Clone, { #[inline] fn clone(&self) -> Self { @@ -1971,8 +1934,7 @@ impl<A, E, V: FromIterator<A>> FromIterator<Result<A, E>> for Result<V, E> { } #[unstable(feature = "try_trait_v2", issue = "84277")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T, E> const ops::Try for Result<T, E> { +impl<T, E> ops::Try for Result<T, E> { type Output = T; type Residual = Result<convert::Infallible, E>; @@ -1991,10 +1953,7 @@ impl<T, E> const ops::Try for Result<T, E> { } #[unstable(feature = "try_trait_v2", issue = "84277")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T, E, F: ~const From<E>> const ops::FromResidual<Result<convert::Infallible, E>> - for Result<T, F> -{ +impl<T, E, F: From<E>> ops::FromResidual<Result<convert::Infallible, E>> for Result<T, F> { #[inline] #[track_caller] fn from_residual(residual: Result<convert::Infallible, E>) -> Self { @@ -2013,7 +1972,6 @@ impl<T, E, F: From<E>> ops::FromResidual<ops::Yeet<E>> for Result<T, F> { } #[unstable(feature = "try_trait_v2_residual", issue = "91285")] -#[rustc_const_unstable(feature = "const_try", issue = "74935")] -impl<T, E> const ops::Residual<T> for Result<convert::Infallible, E> { +impl<T, E> ops::Residual<T> for Result<convert::Infallible, E> { type TryType = Result<T, E>; } diff --git a/library/core/src/slice/ascii.rs b/library/core/src/slice/ascii.rs index 5e5399acc..f3311f76a 100644 --- a/library/core/src/slice/ascii.rs +++ b/library/core/src/slice/ascii.rs @@ -10,12 +10,43 @@ use crate::ops; impl [u8] { /// Checks if all bytes in this slice are within the ASCII range. #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")] + #[rustc_const_unstable(feature = "const_slice_is_ascii", issue = "111090")] #[must_use] #[inline] - pub fn is_ascii(&self) -> bool { + pub const fn is_ascii(&self) -> bool { is_ascii(self) } + /// If this slice [`is_ascii`](Self::is_ascii), returns it as a slice of + /// [ASCII characters](`ascii::Char`), otherwise returns `None`. + #[unstable(feature = "ascii_char", issue = "110998")] + #[must_use] + #[inline] + pub const fn as_ascii(&self) -> Option<&[ascii::Char]> { + if self.is_ascii() { + // SAFETY: Just checked that it's ASCII + Some(unsafe { self.as_ascii_unchecked() }) + } else { + None + } + } + + /// Converts this slice of bytes into a slice of ASCII characters, + /// without checking whether they're valid. + /// + /// # Safety + /// + /// Every byte in the slice must be in `0..=127`, or else this is UB. + #[unstable(feature = "ascii_char", issue = "110998")] + #[must_use] + #[inline] + pub const unsafe fn as_ascii_unchecked(&self) -> &[ascii::Char] { + let byte_ptr: *const [u8] = self; + let ascii_ptr = byte_ptr as *const [ascii::Char]; + // SAFETY: The caller promised all the bytes are ASCII + unsafe { &*ascii_ptr } + } + /// Checks that two slices are an ASCII case-insensitive match. /// /// Same as `to_ascii_lowercase(a) == to_ascii_lowercase(b)`, @@ -232,11 +263,29 @@ impl<'a> fmt::Debug for EscapeAscii<'a> { /// Returns `true` if any byte in the word `v` is nonascii (>= 128). Snarfed /// from `../str/mod.rs`, which does something similar for utf8 validation. #[inline] -fn contains_nonascii(v: usize) -> bool { +const fn contains_nonascii(v: usize) -> bool { const NONASCII_MASK: usize = usize::repeat_u8(0x80); (NONASCII_MASK & v) != 0 } +/// ASCII test *without* the chunk-at-a-time optimizations. +/// +/// This is carefully structured to produce nice small code -- it's smaller in +/// `-O` than what the "obvious" ways produces under `-C opt-level=s`. If you +/// touch it, be sure to run (and update if needed) the assembly test. +#[unstable(feature = "str_internals", issue = "none")] +#[doc(hidden)] +#[inline] +pub const fn is_ascii_simple(mut bytes: &[u8]) -> bool { + while let [rest @ .., last] = bytes { + if !last.is_ascii() { + break; + } + bytes = rest; + } + bytes.is_empty() +} + /// Optimized ASCII test that will use usize-at-a-time operations instead of /// byte-at-a-time operations (when possible). /// @@ -250,7 +299,7 @@ fn contains_nonascii(v: usize) -> bool { /// If any of these loads produces something for which `contains_nonascii` /// (above) returns true, then we know the answer is false. #[inline] -fn is_ascii(s: &[u8]) -> bool { +const fn is_ascii(s: &[u8]) -> bool { const USIZE_SIZE: usize = mem::size_of::<usize>(); let len = s.len(); @@ -262,7 +311,7 @@ fn is_ascii(s: &[u8]) -> bool { // We also do this for architectures where `size_of::<usize>()` isn't // sufficient alignment for `usize`, because it's a weird edge case. if len < USIZE_SIZE || len < align_offset || USIZE_SIZE < mem::align_of::<usize>() { - return s.iter().all(|b| b.is_ascii()); + return is_ascii_simple(s); } // We always read the first word unaligned, which means `align_offset` is @@ -291,18 +340,26 @@ fn is_ascii(s: &[u8]) -> bool { // Paranoia check about alignment, since we're about to do a bunch of // unaligned loads. In practice this should be impossible barring a bug in // `align_offset` though. - debug_assert_eq!(word_ptr.addr() % mem::align_of::<usize>(), 0); + // While this method is allowed to spuriously fail in CTFE, if it doesn't + // have alignment information it should have given a `usize::MAX` for + // `align_offset` earlier, sending things through the scalar path instead of + // this one, so this check should pass if it's reachable. + debug_assert!(word_ptr.is_aligned_to(mem::align_of::<usize>())); // Read subsequent words until the last aligned word, excluding the last // aligned word by itself to be done in tail check later, to ensure that // tail is always one `usize` at most to extra branch `byte_pos == len`. while byte_pos < len - USIZE_SIZE { - debug_assert!( - // Sanity check that the read is in bounds - (word_ptr.addr() + USIZE_SIZE) <= start.addr().wrapping_add(len) && - // And that our assumptions about `byte_pos` hold. - (word_ptr.addr() - start.addr()) == byte_pos - ); + // Sanity check that the read is in bounds + debug_assert!(byte_pos + USIZE_SIZE <= len); + // And that our assumptions about `byte_pos` hold. + debug_assert!(matches!( + word_ptr.cast::<u8>().guaranteed_eq(start.wrapping_add(byte_pos)), + // These are from the same allocation, so will hopefully always be + // known to match even in CTFE, but if it refuses to compare them + // that's ok since it's just a debug check anyway. + None | Some(true), + )); // SAFETY: We know `word_ptr` is properly aligned (because of // `align_offset`), and we know that we have enough bytes between `word_ptr` and the end diff --git a/library/core/src/slice/index.rs b/library/core/src/slice/index.rs index 353935324..6ef9f9c95 100644 --- a/library/core/src/slice/index.rs +++ b/library/core/src/slice/index.rs @@ -7,10 +7,9 @@ use crate::ops; use crate::ptr; #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -impl<T, I> const ops::Index<I> for [T] +impl<T, I> ops::Index<I> for [T] where - I: ~const SliceIndex<[T]>, + I: SliceIndex<[T]>, { type Output = I::Output; @@ -21,10 +20,9 @@ where } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -impl<T, I> const ops::IndexMut<I> for [T] +impl<T, I> ops::IndexMut<I> for [T] where - I: ~const SliceIndex<[T]>, + I: SliceIndex<[T]>, { #[inline] fn index_mut(&mut self, index: I) -> &mut I::Output { @@ -162,7 +160,6 @@ mod private_slice_index { message = "the type `{T}` cannot be indexed by `{Self}`", label = "slice indices are of type `usize` or ranges of `usize`" )] -#[const_trait] pub unsafe trait SliceIndex<T: ?Sized>: private_slice_index::Sealed { /// The output type returned by methods. #[stable(feature = "slice_get_slice", since = "1.28.0")] @@ -211,7 +208,7 @@ pub unsafe trait SliceIndex<T: ?Sized>: private_slice_index::Sealed { #[stable(feature = "slice_get_slice_impls", since = "1.15.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl<T> const SliceIndex<[T]> for usize { +unsafe impl<T> SliceIndex<[T]> for usize { type Output = T; #[inline] @@ -271,7 +268,7 @@ unsafe impl<T> const SliceIndex<[T]> for usize { /// Because `IndexRange` guarantees `start <= end`, fewer checks are needed here /// than there are for a general `Range<usize>` (which might be `100..3`). #[rustc_const_unstable(feature = "const_index_range_slice_index", issue = "none")] -unsafe impl<T> const SliceIndex<[T]> for ops::IndexRange { +unsafe impl<T> SliceIndex<[T]> for ops::IndexRange { type Output = [T]; #[inline] @@ -347,7 +344,7 @@ unsafe impl<T> const SliceIndex<[T]> for ops::IndexRange { #[stable(feature = "slice_get_slice_impls", since = "1.15.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl<T> const SliceIndex<[T]> for ops::Range<usize> { +unsafe impl<T> SliceIndex<[T]> for ops::Range<usize> { type Output = [T]; #[inline] @@ -428,7 +425,7 @@ unsafe impl<T> const SliceIndex<[T]> for ops::Range<usize> { #[stable(feature = "slice_get_slice_impls", since = "1.15.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl<T> const SliceIndex<[T]> for ops::RangeTo<usize> { +unsafe impl<T> SliceIndex<[T]> for ops::RangeTo<usize> { type Output = [T]; #[inline] @@ -466,7 +463,7 @@ unsafe impl<T> const SliceIndex<[T]> for ops::RangeTo<usize> { #[stable(feature = "slice_get_slice_impls", since = "1.15.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl<T> const SliceIndex<[T]> for ops::RangeFrom<usize> { +unsafe impl<T> SliceIndex<[T]> for ops::RangeFrom<usize> { type Output = [T]; #[inline] @@ -512,7 +509,7 @@ unsafe impl<T> const SliceIndex<[T]> for ops::RangeFrom<usize> { #[stable(feature = "slice_get_slice_impls", since = "1.15.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl<T> const SliceIndex<[T]> for ops::RangeFull { +unsafe impl<T> SliceIndex<[T]> for ops::RangeFull { type Output = [T]; #[inline] @@ -548,7 +545,7 @@ unsafe impl<T> const SliceIndex<[T]> for ops::RangeFull { #[stable(feature = "inclusive_range", since = "1.26.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl<T> const SliceIndex<[T]> for ops::RangeInclusive<usize> { +unsafe impl<T> SliceIndex<[T]> for ops::RangeInclusive<usize> { type Output = [T]; #[inline] @@ -592,7 +589,7 @@ unsafe impl<T> const SliceIndex<[T]> for ops::RangeInclusive<usize> { #[stable(feature = "inclusive_range", since = "1.26.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl<T> const SliceIndex<[T]> for ops::RangeToInclusive<usize> { +unsafe impl<T> SliceIndex<[T]> for ops::RangeToInclusive<usize> { type Output = [T]; #[inline] diff --git a/library/core/src/slice/iter.rs b/library/core/src/slice/iter.rs index 88b84bd13..5369fe0a9 100644 --- a/library/core/src/slice/iter.rs +++ b/library/core/src/slice/iter.rs @@ -13,7 +13,7 @@ use crate::iter::{ use crate::marker::{PhantomData, Send, Sized, Sync}; use crate::mem::{self, SizedTypeProperties}; use crate::num::NonZeroUsize; -use crate::ptr::NonNull; +use crate::ptr::{invalid, invalid_mut, NonNull}; use super::{from_raw_parts, from_raw_parts_mut}; @@ -60,10 +60,15 @@ impl<'a, T> IntoIterator for &'a mut [T] { #[stable(feature = "rust1", since = "1.0.0")] #[must_use = "iterators are lazy and do nothing unless consumed"] pub struct Iter<'a, T: 'a> { + /// The pointer to the next element to return, or the past-the-end location + /// if the iterator is empty. + /// + /// This address will be used for all ZST elements, never changed. ptr: NonNull<T>, - end: *const T, // If T is a ZST, this is actually ptr+len. This encoding is picked so that - // ptr == end is a quick test for the Iterator being empty, that works - // for both ZST and non-ZST. + /// For non-ZSTs, the non-null pointer to the past-the-end element. + /// + /// For ZSTs, this is `ptr::invalid(len)`. + end: *const T, _marker: PhantomData<&'a T>, } @@ -85,10 +90,7 @@ impl<'a, T> Iter<'a, T> { let ptr = slice.as_ptr(); // SAFETY: Similar to `IterMut::new`. unsafe { - assume(!ptr.is_null()); - - let end = - if T::IS_ZST { ptr.wrapping_byte_add(slice.len()) } else { ptr.add(slice.len()) }; + let end = if T::IS_ZST { invalid(slice.len()) } else { ptr.add(slice.len()) }; Self { ptr: NonNull::new_unchecked(ptr as *mut T), end, _marker: PhantomData } } @@ -179,10 +181,15 @@ impl<T> AsRef<[T]> for Iter<'_, T> { #[stable(feature = "rust1", since = "1.0.0")] #[must_use = "iterators are lazy and do nothing unless consumed"] pub struct IterMut<'a, T: 'a> { + /// The pointer to the next element to return, or the past-the-end location + /// if the iterator is empty. + /// + /// This address will be used for all ZST elements, never changed. ptr: NonNull<T>, - end: *mut T, // If T is a ZST, this is actually ptr+len. This encoding is picked so that - // ptr == end is a quick test for the Iterator being empty, that works - // for both ZST and non-ZST. + /// For non-ZSTs, the non-null pointer to the past-the-end element. + /// + /// For ZSTs, this is `ptr::invalid_mut(len)`. + end: *mut T, _marker: PhantomData<&'a mut T>, } @@ -219,10 +226,7 @@ impl<'a, T> IterMut<'a, T> { // See the `next_unchecked!` and `is_empty!` macros as well as the // `post_inc_start` method for more information. unsafe { - assume(!ptr.is_null()); - - let end = - if T::IS_ZST { ptr.wrapping_byte_add(slice.len()) } else { ptr.add(slice.len()) }; + let end = if T::IS_ZST { invalid_mut(slice.len()) } else { ptr.add(slice.len()) }; Self { ptr: NonNull::new_unchecked(ptr), end, _marker: PhantomData } } @@ -685,7 +689,7 @@ where None } else { self.finished = true; - Some(mem::replace(&mut self.v, &mut [])) + Some(mem::take(&mut self.v)) } } } @@ -749,7 +753,7 @@ where match idx_opt { None => self.finish(), Some(idx) => { - let tmp = mem::replace(&mut self.v, &mut []); + let tmp = mem::take(&mut self.v); let (head, tail) = tmp.split_at_mut(idx); self.v = head; Some(&mut tail[1..]) @@ -830,7 +834,7 @@ where if idx == self.v.len() { self.finished = true; } - let tmp = mem::replace(&mut self.v, &mut []); + let tmp = mem::take(&mut self.v); let (head, tail) = tmp.split_at_mut(idx); self.v = tail; Some(head) @@ -876,7 +880,7 @@ where if idx == 0 { self.finished = true; } - let tmp = mem::replace(&mut self.v, &mut []); + let tmp = mem::take(&mut self.v); let (head, tail) = tmp.split_at_mut(idx); self.v = head; Some(tail) diff --git a/library/core/src/slice/iter/macros.rs b/library/core/src/slice/iter/macros.rs index 392752f2a..3462c0e02 100644 --- a/library/core/src/slice/iter/macros.rs +++ b/library/core/src/slice/iter/macros.rs @@ -1,11 +1,30 @@ //! Macros used by iterators of slice. +// Shrinks the iterator when T is a ZST, setting the length to `new_len`. +// `new_len` must not exceed `self.len()`. +macro_rules! zst_set_len { + ($self: ident, $new_len: expr) => {{ + #![allow(unused_unsafe)] // we're sometimes used within an unsafe block + + // SAFETY: same as `invalid(_mut)`, but the macro doesn't know + // which versions of that function to call, so open-code it. + $self.end = unsafe { mem::transmute::<usize, _>($new_len) }; + }}; +} + +// Shrinks the iterator when T is a ZST, reducing the length by `n`. +// `n` must not exceed `self.len()`. +macro_rules! zst_shrink { + ($self: ident, $n: ident) => { + let new_len = $self.end.addr() - $n; + zst_set_len!($self, new_len); + }; +} + // Inlining is_empty and len makes a huge performance difference macro_rules! is_empty { - // The way we encode the length of a ZST iterator, this works both for ZST - // and non-ZST. ($self: ident) => { - $self.ptr.as_ptr() as *const T == $self.end + if T::IS_ZST { $self.end.addr() == 0 } else { $self.ptr.as_ptr() as *const _ == $self.end } }; } @@ -13,16 +32,13 @@ macro_rules! len { ($self: ident) => {{ #![allow(unused_unsafe)] // we're sometimes used within an unsafe block - let start = $self.ptr; if T::IS_ZST { - // This _cannot_ use `ptr_sub` because we depend on wrapping - // to represent the length of long ZST slice iterators. - $self.end.addr().wrapping_sub(start.as_ptr().addr()) + $self.end.addr() } else { // To get rid of some bounds checks (see `position`), we use ptr_sub instead of // offset_from (Tested by `codegen/slice-position-bounds-check`.) // SAFETY: by the type invariant pointers are aligned and `start <= end` - unsafe { $self.end.sub_ptr(start.as_ptr()) } + unsafe { $self.end.sub_ptr($self.ptr.as_ptr()) } } }}; } @@ -50,14 +66,6 @@ macro_rules! iterator { ($self: ident) => {& $( $mut_ )? *$self.pre_dec_end(1)} } - // Shrinks the iterator when T is a ZST, by moving the end of the iterator - // backwards by `n`. `n` must not exceed `self.len()`. - macro_rules! zst_shrink { - ($self: ident, $n: ident) => { - $self.end = $self.end.wrapping_byte_sub($n); - } - } - impl<'a, T> $name<'a, T> { // Helper function for creating a slice from the iterator. #[inline(always)] @@ -73,16 +81,15 @@ macro_rules! iterator { // Unsafe because the offset must not exceed `self.len()`. #[inline(always)] unsafe fn post_inc_start(&mut self, offset: usize) -> * $raw_mut T { - if mem::size_of::<T>() == 0 { + let old = self.ptr; + if T::IS_ZST { zst_shrink!(self, offset); - self.ptr.as_ptr() } else { - let old = self.ptr.as_ptr(); // SAFETY: the caller guarantees that `offset` doesn't exceed `self.len()`, // so this new pointer is inside `self` and thus guaranteed to be non-null. - self.ptr = unsafe { NonNull::new_unchecked(self.ptr.as_ptr().add(offset)) }; - old + self.ptr = unsafe { self.ptr.add(offset) }; } + old.as_ptr() } // Helper function for moving the end of the iterator backwards by `offset` elements, @@ -124,12 +131,10 @@ macro_rules! iterator { fn next(&mut self) -> Option<$elem> { // could be implemented with slices, but this avoids bounds checks - // SAFETY: `assume` calls are safe since a slice's start pointer - // must be non-null, and slices over non-ZSTs must also have a - // non-null end pointer. The call to `next_unchecked!` is safe - // since we check if the iterator is empty first. + // SAFETY: `assume` call is safe because slices over non-ZSTs must + // have a non-null end pointer. The call to `next_unchecked!` is + // safe since we check if the iterator is empty first. unsafe { - assume(!self.ptr.as_ptr().is_null()); if !<T>::IS_ZST { assume(!self.end.is_null()); } @@ -157,9 +162,7 @@ macro_rules! iterator { if n >= len!(self) { // This iterator is now empty. if T::IS_ZST { - // We have to do it this way as `ptr` may never be 0, but `end` - // could be (due to wrapping). - self.end = self.ptr.as_ptr(); + zst_set_len!(self, 0); } else { // SAFETY: end can't be 0 if T isn't ZST because ptr isn't 0 and end >= ptr unsafe { @@ -339,12 +342,10 @@ macro_rules! iterator { fn next_back(&mut self) -> Option<$elem> { // could be implemented with slices, but this avoids bounds checks - // SAFETY: `assume` calls are safe since a slice's start pointer must be non-null, - // and slices over non-ZSTs must also have a non-null end pointer. - // The call to `next_back_unchecked!` is safe since we check if the iterator is - // empty first. + // SAFETY: `assume` call is safe because slices over non-ZSTs must + // have a non-null end pointer. The call to `next_back_unchecked!` + // is safe since we check if the iterator is empty first. unsafe { - assume(!self.ptr.as_ptr().is_null()); if !<T>::IS_ZST { assume(!self.end.is_null()); } @@ -360,7 +361,11 @@ macro_rules! iterator { fn nth_back(&mut self, n: usize) -> Option<$elem> { if n >= len!(self) { // This iterator is now empty. - self.end = self.ptr.as_ptr(); + if T::IS_ZST { + zst_set_len!(self, 0); + } else { + self.end = self.ptr.as_ptr(); + } return None; } // SAFETY: We are in bounds. `pre_dec_end` does the right thing even for ZSTs. diff --git a/library/core/src/slice/memchr.rs b/library/core/src/slice/memchr.rs index 98c8349eb..3a8b59d72 100644 --- a/library/core/src/slice/memchr.rs +++ b/library/core/src/slice/memchr.rs @@ -1,7 +1,6 @@ // Original implementation taken from rust-memchr. // Copyright 2015 Andrew Gallant, bluss and Nicolas Koch -use crate::cmp; use crate::mem; const LO_USIZE: usize = usize::repeat_u8(0x01); @@ -83,8 +82,12 @@ const fn memchr_aligned(x: u8, text: &[u8]) -> Option<usize> { let mut offset = ptr.align_offset(USIZE_BYTES); if offset > 0 { - offset = cmp::min(offset, len); - if let Some(index) = memchr_naive(x, &text[..offset]) { + // FIXME(const-hack, fee1-dead): replace with min + offset = if offset < len { offset } else { len }; + // FIXME(const-hack, fee1-dead): replace with range slicing + // SAFETY: offset is within bounds + let slice = unsafe { super::from_raw_parts(text.as_ptr(), offset) }; + if let Some(index) = memchr_naive(x, slice) { return Some(index); } } @@ -110,7 +113,10 @@ const fn memchr_aligned(x: u8, text: &[u8]) -> Option<usize> { // Find the byte after the point the body loop stopped. // FIXME(const-hack): Use `?` instead. - if let Some(i) = memchr_naive(x, &text[offset..]) { Some(offset + i) } else { None } + // FIXME(const-hack, fee1-dead): use range slicing + // SAFETY: offset is within bounds + let slice = unsafe { super::from_raw_parts(text.as_ptr().add(offset), text.len() - offset) }; + if let Some(i) = memchr_naive(x, slice) { Some(offset + i) } else { None } } /// Returns the last index matching the byte `x` in `text`. diff --git a/library/core/src/slice/mod.rs b/library/core/src/slice/mod.rs index f541808a6..ea0181e35 100644 --- a/library/core/src/slice/mod.rs +++ b/library/core/src/slice/mod.rs @@ -42,8 +42,13 @@ mod index; mod iter; mod raw; mod rotate; +mod select; mod specialize; +#[unstable(feature = "str_internals", issue = "none")] +#[doc(hidden)] +pub use ascii::is_ascii_simple; + #[stable(feature = "rust1", since = "1.0.0")] pub use iter::{Chunks, ChunksMut, Windows}; #[stable(feature = "rust1", since = "1.0.0")] @@ -315,6 +320,264 @@ impl<T> [T] { if let [.., last] = self { Some(last) } else { None } } + /// Returns the first `N` elements of the slice, or `None` if it has fewer than `N` elements. + /// + /// # Examples + /// + /// ``` + /// #![feature(slice_first_last_chunk)] + /// + /// let u = [10, 40, 30]; + /// assert_eq!(Some(&[10, 40]), u.first_chunk::<2>()); + /// + /// let v: &[i32] = &[10]; + /// assert_eq!(None, v.first_chunk::<2>()); + /// + /// let w: &[i32] = &[]; + /// assert_eq!(Some(&[]), w.first_chunk::<0>()); + /// ``` + #[unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[rustc_const_unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[inline] + pub const fn first_chunk<const N: usize>(&self) -> Option<&[T; N]> { + if self.len() < N { + None + } else { + // SAFETY: We explicitly check for the correct number of elements, + // and do not let the reference outlive the slice. + Some(unsafe { &*(self.as_ptr() as *const [T; N]) }) + } + } + + /// Returns a mutable reference to the first `N` elements of the slice, + /// or `None` if it has fewer than `N` elements. + /// + /// # Examples + /// + /// ``` + /// #![feature(slice_first_last_chunk)] + /// + /// let x = &mut [0, 1, 2]; + /// + /// if let Some(first) = x.first_chunk_mut::<2>() { + /// first[0] = 5; + /// first[1] = 4; + /// } + /// assert_eq!(x, &[5, 4, 2]); + /// ``` + #[unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[rustc_const_unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[inline] + pub const fn first_chunk_mut<const N: usize>(&mut self) -> Option<&mut [T; N]> { + if self.len() < N { + None + } else { + // SAFETY: We explicitly check for the correct number of elements, + // do not let the reference outlive the slice, + // and require exclusive access to the entire slice to mutate the chunk. + Some(unsafe { &mut *(self.as_mut_ptr() as *mut [T; N]) }) + } + } + + /// Returns the first `N` elements of the slice and the remainder, + /// or `None` if it has fewer than `N` elements. + /// + /// # Examples + /// + /// ``` + /// #![feature(slice_first_last_chunk)] + /// + /// let x = &[0, 1, 2]; + /// + /// if let Some((first, elements)) = x.split_first_chunk::<2>() { + /// assert_eq!(first, &[0, 1]); + /// assert_eq!(elements, &[2]); + /// } + /// ``` + #[unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[rustc_const_unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[inline] + pub const fn split_first_chunk<const N: usize>(&self) -> Option<(&[T; N], &[T])> { + if self.len() < N { + None + } else { + // SAFETY: We manually verified the bounds of the split. + let (first, tail) = unsafe { self.split_at_unchecked(N) }; + + // SAFETY: We explicitly check for the correct number of elements, + // and do not let the references outlive the slice. + Some((unsafe { &*(first.as_ptr() as *const [T; N]) }, tail)) + } + } + + /// Returns a mutable reference to the first `N` elements of the slice and the remainder, + /// or `None` if it has fewer than `N` elements. + /// + /// # Examples + /// + /// ``` + /// #![feature(slice_first_last_chunk)] + /// + /// let x = &mut [0, 1, 2]; + /// + /// if let Some((first, elements)) = x.split_first_chunk_mut::<2>() { + /// first[0] = 3; + /// first[1] = 4; + /// elements[0] = 5; + /// } + /// assert_eq!(x, &[3, 4, 5]); + /// ``` + #[unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[rustc_const_unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[inline] + pub const fn split_first_chunk_mut<const N: usize>( + &mut self, + ) -> Option<(&mut [T; N], &mut [T])> { + if self.len() < N { + None + } else { + // SAFETY: We manually verified the bounds of the split. + let (first, tail) = unsafe { self.split_at_mut_unchecked(N) }; + + // SAFETY: We explicitly check for the correct number of elements, + // do not let the reference outlive the slice, + // and enforce exclusive mutability of the chunk by the split. + Some((unsafe { &mut *(first.as_mut_ptr() as *mut [T; N]) }, tail)) + } + } + + /// Returns the last `N` elements of the slice and the remainder, + /// or `None` if it has fewer than `N` elements. + /// + /// # Examples + /// + /// ``` + /// #![feature(slice_first_last_chunk)] + /// + /// let x = &[0, 1, 2]; + /// + /// if let Some((last, elements)) = x.split_last_chunk::<2>() { + /// assert_eq!(last, &[1, 2]); + /// assert_eq!(elements, &[0]); + /// } + /// ``` + #[unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[rustc_const_unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[inline] + pub const fn split_last_chunk<const N: usize>(&self) -> Option<(&[T; N], &[T])> { + if self.len() < N { + None + } else { + // SAFETY: We manually verified the bounds of the split. + let (init, last) = unsafe { self.split_at_unchecked(self.len() - N) }; + + // SAFETY: We explicitly check for the correct number of elements, + // and do not let the references outlive the slice. + Some((unsafe { &*(last.as_ptr() as *const [T; N]) }, init)) + } + } + + /// Returns the last and all the rest of the elements of the slice, or `None` if it is empty. + /// + /// # Examples + /// + /// ``` + /// #![feature(slice_first_last_chunk)] + /// + /// let x = &mut [0, 1, 2]; + /// + /// if let Some((last, elements)) = x.split_last_chunk_mut::<2>() { + /// last[0] = 3; + /// last[1] = 4; + /// elements[0] = 5; + /// } + /// assert_eq!(x, &[5, 3, 4]); + /// ``` + #[unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[rustc_const_unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[inline] + pub const fn split_last_chunk_mut<const N: usize>( + &mut self, + ) -> Option<(&mut [T; N], &mut [T])> { + if self.len() < N { + None + } else { + // SAFETY: We manually verified the bounds of the split. + let (init, last) = unsafe { self.split_at_mut_unchecked(self.len() - N) }; + + // SAFETY: We explicitly check for the correct number of elements, + // do not let the reference outlive the slice, + // and enforce exclusive mutability of the chunk by the split. + Some((unsafe { &mut *(last.as_mut_ptr() as *mut [T; N]) }, init)) + } + } + + /// Returns the last element of the slice, or `None` if it is empty. + /// + /// # Examples + /// + /// ``` + /// #![feature(slice_first_last_chunk)] + /// + /// let u = [10, 40, 30]; + /// assert_eq!(Some(&[40, 30]), u.last_chunk::<2>()); + /// + /// let v: &[i32] = &[10]; + /// assert_eq!(None, v.last_chunk::<2>()); + /// + /// let w: &[i32] = &[]; + /// assert_eq!(Some(&[]), w.last_chunk::<0>()); + /// ``` + #[unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[rustc_const_unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[inline] + pub const fn last_chunk<const N: usize>(&self) -> Option<&[T; N]> { + if self.len() < N { + None + } else { + // SAFETY: We manually verified the bounds of the slice. + // FIXME: Without const traits, we need this instead of `get_unchecked`. + let last = unsafe { self.split_at_unchecked(self.len() - N).1 }; + + // SAFETY: We explicitly check for the correct number of elements, + // and do not let the references outlive the slice. + Some(unsafe { &*(last.as_ptr() as *const [T; N]) }) + } + } + + /// Returns a mutable pointer to the last item in the slice. + /// + /// # Examples + /// + /// ``` + /// #![feature(slice_first_last_chunk)] + /// + /// let x = &mut [0, 1, 2]; + /// + /// if let Some(last) = x.last_chunk_mut::<2>() { + /// last[0] = 10; + /// last[1] = 20; + /// } + /// assert_eq!(x, &[0, 10, 20]); + /// ``` + #[unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[rustc_const_unstable(feature = "slice_first_last_chunk", issue = "111774")] + #[inline] + pub const fn last_chunk_mut<const N: usize>(&mut self) -> Option<&mut [T; N]> { + if self.len() < N { + None + } else { + // SAFETY: We manually verified the bounds of the slice. + // FIXME: Without const traits, we need this instead of `get_unchecked`. + let last = unsafe { self.split_at_mut_unchecked(self.len() - N).1 }; + + // SAFETY: We explicitly check for the correct number of elements, + // do not let the reference outlive the slice, + // and require exclusive access to the entire slice to mutate the chunk. + Some(unsafe { &mut *(last.as_mut_ptr() as *mut [T; N]) }) + } + } + /// Returns a reference to an element or subslice depending on the type of /// index. /// @@ -333,12 +596,11 @@ impl<T> [T] { /// assert_eq!(None, v.get(0..4)); /// ``` #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] #[inline] #[must_use] - pub const fn get<I>(&self, index: I) -> Option<&I::Output> + pub fn get<I>(&self, index: I) -> Option<&I::Output> where - I: ~const SliceIndex<Self>, + I: SliceIndex<Self>, { index.get(self) } @@ -359,12 +621,11 @@ impl<T> [T] { /// assert_eq!(x, &[0, 42, 2]); /// ``` #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] #[inline] #[must_use] - pub const fn get_mut<I>(&mut self, index: I) -> Option<&mut I::Output> + pub fn get_mut<I>(&mut self, index: I) -> Option<&mut I::Output> where - I: ~const SliceIndex<Self>, + I: SliceIndex<Self>, { index.get_mut(self) } @@ -392,12 +653,11 @@ impl<T> [T] { /// } /// ``` #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] #[inline] #[must_use] - pub const unsafe fn get_unchecked<I>(&self, index: I) -> &I::Output + pub unsafe fn get_unchecked<I>(&self, index: I) -> &I::Output where - I: ~const SliceIndex<Self>, + I: SliceIndex<Self>, { // SAFETY: the caller must uphold most of the safety requirements for `get_unchecked`; // the slice is dereferenceable because `self` is a safe reference. @@ -430,12 +690,11 @@ impl<T> [T] { /// assert_eq!(x, &[1, 13, 4]); /// ``` #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] #[inline] #[must_use] - pub const unsafe fn get_unchecked_mut<I>(&mut self, index: I) -> &mut I::Output + pub unsafe fn get_unchecked_mut<I>(&mut self, index: I) -> &mut I::Output where - I: ~const SliceIndex<Self>, + I: SliceIndex<Self>, { // SAFETY: the caller must uphold the safety requirements for `get_unchecked_mut`; // the slice is dereferenceable because `self` is a safe reference. @@ -678,9 +937,8 @@ impl<T> [T] { /// assert!(v == [3, 2, 1]); /// ``` #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_reverse", issue = "100784")] #[inline] - pub const fn reverse(&mut self) { + pub fn reverse(&mut self) { let half_len = self.len() / 2; let Range { start, end } = self.as_mut_ptr_range(); @@ -703,7 +961,7 @@ impl<T> [T] { revswap(front_half, back_half, half_len); #[inline] - const fn revswap<T>(a: &mut [T], b: &mut [T], n: usize) { + fn revswap<T>(a: &mut [T], b: &mut [T], n: usize) { debug_assert!(a.len() == n); debug_assert!(b.len() == n); @@ -996,7 +1254,7 @@ impl<T> [T] { #[unstable(feature = "slice_as_chunks", issue = "74985")] #[inline] #[must_use] - pub unsafe fn as_chunks_unchecked<const N: usize>(&self) -> &[[T; N]] { + pub const unsafe fn as_chunks_unchecked<const N: usize>(&self) -> &[[T; N]] { let this = self; // SAFETY: Caller must guarantee that `N` is nonzero and exactly divides the slice length let new_len = unsafe { @@ -1044,7 +1302,7 @@ impl<T> [T] { #[inline] #[track_caller] #[must_use] - pub fn as_chunks<const N: usize>(&self) -> (&[[T; N]], &[T]) { + pub const fn as_chunks<const N: usize>(&self) -> (&[[T; N]], &[T]) { assert!(N != 0, "chunk size must be non-zero"); let len = self.len() / N; let (multiple_of_n, remainder) = self.split_at(len * N); @@ -1076,7 +1334,7 @@ impl<T> [T] { #[inline] #[track_caller] #[must_use] - pub fn as_rchunks<const N: usize>(&self) -> (&[T], &[[T; N]]) { + pub const fn as_rchunks<const N: usize>(&self) -> (&[T], &[[T; N]]) { assert!(N != 0, "chunk size must be non-zero"); let len = self.len() / N; let (remainder, multiple_of_n) = self.split_at(self.len() - len * N); @@ -1153,7 +1411,7 @@ impl<T> [T] { #[unstable(feature = "slice_as_chunks", issue = "74985")] #[inline] #[must_use] - pub unsafe fn as_chunks_unchecked_mut<const N: usize>(&mut self) -> &mut [[T; N]] { + pub const unsafe fn as_chunks_unchecked_mut<const N: usize>(&mut self) -> &mut [[T; N]] { let this = &*self; // SAFETY: Caller must guarantee that `N` is nonzero and exactly divides the slice length let new_len = unsafe { @@ -1196,7 +1454,7 @@ impl<T> [T] { #[inline] #[track_caller] #[must_use] - pub fn as_chunks_mut<const N: usize>(&mut self) -> (&mut [[T; N]], &mut [T]) { + pub const fn as_chunks_mut<const N: usize>(&mut self) -> (&mut [[T; N]], &mut [T]) { assert!(N != 0, "chunk size must be non-zero"); let len = self.len() / N; let (multiple_of_n, remainder) = self.split_at_mut(len * N); @@ -1234,7 +1492,7 @@ impl<T> [T] { #[inline] #[track_caller] #[must_use] - pub fn as_rchunks_mut<const N: usize>(&mut self) -> (&mut [T], &mut [[T; N]]) { + pub const fn as_rchunks_mut<const N: usize>(&mut self) -> (&mut [T], &mut [[T; N]]) { assert!(N != 0, "chunk size must be non-zero"); let len = self.len() / N; let (remainder, multiple_of_n) = self.split_at_mut(self.len() - len * N); @@ -1596,7 +1854,8 @@ impl<T> [T] { /// } /// ``` #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_slice_split_at_not_mut", issue = "101158")] + #[rustc_const_stable(feature = "const_slice_split_at_not_mut", since = "1.71.0")] + #[rustc_allow_const_fn_unstable(slice_split_at_unchecked)] #[inline] #[track_caller] #[must_use] @@ -2746,8 +3005,9 @@ impl<T> [T] { /// /// # Current implementation /// - /// The current algorithm is based on the quickselect portion of the same quicksort algorithm - /// used for [`sort_unstable`]. + /// The current algorithm is an introselect implementation based on Pattern Defeating Quicksort, which is also + /// the basis for [`sort_unstable`]. The fallback algorithm is Median of Medians using Tukey's Ninther for + /// pivot selection, which guarantees linear runtime for all inputs. /// /// [`sort_unstable`]: slice::sort_unstable /// @@ -2776,7 +3036,7 @@ impl<T> [T] { where T: Ord, { - sort::partition_at_index(self, index, T::lt) + select::partition_at_index(self, index, T::lt) } /// Reorder the slice with a comparator function such that the element at `index` is at its @@ -2797,8 +3057,9 @@ impl<T> [T] { /// /// # Current implementation /// - /// The current algorithm is based on the quickselect portion of the same quicksort algorithm - /// used for [`sort_unstable`]. + /// The current algorithm is an introselect implementation based on Pattern Defeating Quicksort, which is also + /// the basis for [`sort_unstable`]. The fallback algorithm is Median of Medians using Tukey's Ninther for + /// pivot selection, which guarantees linear runtime for all inputs. /// /// [`sort_unstable`]: slice::sort_unstable /// @@ -2831,7 +3092,7 @@ impl<T> [T] { where F: FnMut(&T, &T) -> Ordering, { - sort::partition_at_index(self, index, |a: &T, b: &T| compare(a, b) == Less) + select::partition_at_index(self, index, |a: &T, b: &T| compare(a, b) == Less) } /// Reorder the slice with a key extraction function such that the element at `index` is at its @@ -2887,7 +3148,7 @@ impl<T> [T] { F: FnMut(&T) -> K, K: Ord, { - sort::partition_at_index(self, index, |a: &T, b: &T| f(a).lt(&f(b))) + select::partition_at_index(self, index, |a: &T, b: &T| f(a).lt(&f(b))) } /// Moves all consecutive repeated elements to the end of the slice according to the @@ -3479,44 +3740,13 @@ impl<T> [T] { // Ts = size_of::<U> / gcd(size_of::<T>, size_of::<U>) // // Luckily since all this is constant-evaluated... performance here matters not! - #[inline] - fn gcd(a: usize, b: usize) -> usize { - use crate::intrinsics; - // iterative stein’s algorithm - // We should still make this `const fn` (and revert to recursive algorithm if we do) - // because relying on llvm to consteval all this is… well, it makes me uncomfortable. - - // SAFETY: `a` and `b` are checked to be non-zero values. - let (ctz_a, mut ctz_b) = unsafe { - if a == 0 { - return b; - } - if b == 0 { - return a; - } - (intrinsics::cttz_nonzero(a), intrinsics::cttz_nonzero(b)) - }; - let k = ctz_a.min(ctz_b); - let mut a = a >> ctz_a; - let mut b = b; - loop { - // remove all factors of 2 from b - b >>= ctz_b; - if a > b { - mem::swap(&mut a, &mut b); - } - b = b - a; - // SAFETY: `b` is checked to be non-zero. - unsafe { - if b == 0 { - break; - } - ctz_b = intrinsics::cttz_nonzero(b); - } - } - a << k + const fn gcd(a: usize, b: usize) -> usize { + if b == 0 { a } else { gcd(b, a % b) } } - let gcd: usize = gcd(mem::size_of::<T>(), mem::size_of::<U>()); + + // Explicitly wrap the function call in a const block so it gets + // constant-evaluated even in debug mode. + let gcd: usize = const { gcd(mem::size_of::<T>(), mem::size_of::<U>()) }; let ts: usize = mem::size_of::<U>() / gcd; let us: usize = mem::size_of::<T>() / gcd; @@ -4262,7 +4492,7 @@ impl<T, const N: usize> [[T; N]] { /// assert!(empty_slice_of_arrays.flatten().is_empty()); /// ``` #[unstable(feature = "slice_flatten", issue = "95629")] - pub fn flatten(&self) -> &[T] { + pub const fn flatten(&self) -> &[T] { let len = if T::IS_ZST { self.len().checked_mul(N).expect("slice len overflow") } else { @@ -4404,8 +4634,7 @@ where } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] -impl<T> const Default for &[T] { +impl<T> Default for &[T] { /// Creates an empty slice. fn default() -> Self { &[] @@ -4413,8 +4642,7 @@ impl<T> const Default for &[T] { } #[stable(feature = "mut_slice_default", since = "1.5.0")] -#[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] -impl<T> const Default for &mut [T] { +impl<T> Default for &mut [T] { /// Creates a mutable empty slice. fn default() -> Self { &mut [] @@ -4458,7 +4686,7 @@ impl<T, const N: usize> SlicePattern for [T; N] { /// This will do `binomial(N + 1, 2) = N * (N + 1) / 2 = 0, 1, 3, 6, 10, ..` /// comparison operations. fn get_many_check_valid<const N: usize>(indices: &[usize; N], len: usize) -> bool { - // NB: The optimzer should inline the loops into a sequence + // NB: The optimizer should inline the loops into a sequence // of instructions without additional branching. let mut valid = true; for (i, &idx) in indices.iter().enumerate() { diff --git a/library/core/src/slice/select.rs b/library/core/src/slice/select.rs new file mode 100644 index 000000000..ffc193578 --- /dev/null +++ b/library/core/src/slice/select.rs @@ -0,0 +1,302 @@ +//! Slice selection +//! +//! This module contains the implementation for `slice::select_nth_unstable`. +//! It uses an introselect algorithm based on Orson Peters' pattern-defeating quicksort, +//! published at: <https://github.com/orlp/pdqsort> +//! +//! The fallback algorithm used for introselect is Median of Medians using Tukey's Ninther +//! for pivot selection. Using this as a fallback ensures O(n) worst case running time with +//! better performance than one would get using heapsort as fallback. + +use crate::cmp; +use crate::mem::{self, SizedTypeProperties}; +use crate::slice::sort::{ + break_patterns, choose_pivot, insertion_sort_shift_left, partition, partition_equal, +}; + +// For slices of up to this length it's probably faster to simply sort them. +// Defined at the module scope because it's used in multiple functions. +const MAX_INSERTION: usize = 10; + +fn partition_at_index_loop<'a, T, F>( + mut v: &'a mut [T], + mut index: usize, + is_less: &mut F, + mut pred: Option<&'a T>, +) where + F: FnMut(&T, &T) -> bool, +{ + // Limit the amount of iterations and fall back to fast deterministic selection + // to ensure O(n) worst case running time. This limit needs to be constant, because + // using `ilog2(len)` like in `sort` would result in O(n log n) time complexity. + // The exact value of the limit is chosen somewhat arbitrarily, but for most inputs bad pivot + // selections should be relatively rare, so the limit usually shouldn't be reached + // anyways. + let mut limit = 16; + + // True if the last partitioning was reasonably balanced. + let mut was_balanced = true; + + loop { + if v.len() <= MAX_INSERTION { + if v.len() > 1 { + insertion_sort_shift_left(v, 1, is_less); + } + return; + } + + if limit == 0 { + median_of_medians(v, is_less, index); + return; + } + + // If the last partitioning was imbalanced, try breaking patterns in the slice by shuffling + // some elements around. Hopefully we'll choose a better pivot this time. + if !was_balanced { + break_patterns(v); + limit -= 1; + } + + // Choose a pivot + let (pivot, _) = choose_pivot(v, is_less); + + // If the chosen pivot is equal to the predecessor, then it's the smallest element in the + // slice. Partition the slice into elements equal to and elements greater than the pivot. + // This case is usually hit when the slice contains many duplicate elements. + if let Some(p) = pred { + if !is_less(p, &v[pivot]) { + let mid = partition_equal(v, pivot, is_less); + + // If we've passed our index, then we're good. + if mid > index { + return; + } + + // Otherwise, continue sorting elements greater than the pivot. + v = &mut v[mid..]; + index = index - mid; + pred = None; + continue; + } + } + + let (mid, _) = partition(v, pivot, is_less); + was_balanced = cmp::min(mid, v.len() - mid) >= v.len() / 8; + + // Split the slice into `left`, `pivot`, and `right`. + let (left, right) = v.split_at_mut(mid); + let (pivot, right) = right.split_at_mut(1); + let pivot = &pivot[0]; + + if mid < index { + v = right; + index = index - mid - 1; + pred = Some(pivot); + } else if mid > index { + v = left; + } else { + // If mid == index, then we're done, since partition() guaranteed that all elements + // after mid are greater than or equal to mid. + return; + } + } +} + +/// Helper function that returns the index of the minimum element in the slice using the given +/// comparator function +fn min_index<T, F: FnMut(&T, &T) -> bool>(slice: &[T], is_less: &mut F) -> Option<usize> { + slice + .iter() + .enumerate() + .reduce(|acc, t| if is_less(t.1, acc.1) { t } else { acc }) + .map(|(i, _)| i) +} + +/// Helper function that returns the index of the maximum element in the slice using the given +/// comparator function +fn max_index<T, F: FnMut(&T, &T) -> bool>(slice: &[T], is_less: &mut F) -> Option<usize> { + slice + .iter() + .enumerate() + .reduce(|acc, t| if is_less(acc.1, t.1) { t } else { acc }) + .map(|(i, _)| i) +} + +/// Reorder the slice such that the element at `index` is at its final sorted position. +pub fn partition_at_index<T, F>( + v: &mut [T], + index: usize, + mut is_less: F, +) -> (&mut [T], &mut T, &mut [T]) +where + F: FnMut(&T, &T) -> bool, +{ + if index >= v.len() { + panic!("partition_at_index index {} greater than length of slice {}", index, v.len()); + } + + if T::IS_ZST { + // Sorting has no meaningful behavior on zero-sized types. Do nothing. + } else if index == v.len() - 1 { + // Find max element and place it in the last position of the array. We're free to use + // `unwrap()` here because we know v must not be empty. + let max_idx = max_index(v, &mut is_less).unwrap(); + v.swap(max_idx, index); + } else if index == 0 { + // Find min element and place it in the first position of the array. We're free to use + // `unwrap()` here because we know v must not be empty. + let min_idx = min_index(v, &mut is_less).unwrap(); + v.swap(min_idx, index); + } else { + partition_at_index_loop(v, index, &mut is_less, None); + } + + let (left, right) = v.split_at_mut(index); + let (pivot, right) = right.split_at_mut(1); + let pivot = &mut pivot[0]; + (left, pivot, right) +} + +/// Selection algorithm to select the k-th element from the slice in guaranteed O(n) time. +/// This is essentially a quickselect that uses Tukey's Ninther for pivot selection +fn median_of_medians<T, F: FnMut(&T, &T) -> bool>(mut v: &mut [T], is_less: &mut F, mut k: usize) { + // Since this function isn't public, it should never be called with an out-of-bounds index. + debug_assert!(k < v.len()); + + // If T is as ZST, `partition_at_index` will already return early. + debug_assert!(!T::IS_ZST); + + // We now know that `k < v.len() <= isize::MAX` + loop { + if v.len() <= MAX_INSERTION { + if v.len() > 1 { + insertion_sort_shift_left(v, 1, is_less); + } + return; + } + + // `median_of_{minima,maxima}` can't handle the extreme cases of the first/last element, + // so we catch them here and just do a linear search. + if k == v.len() - 1 { + // Find max element and place it in the last position of the array. We're free to use + // `unwrap()` here because we know v must not be empty. + let max_idx = max_index(v, is_less).unwrap(); + v.swap(max_idx, k); + return; + } else if k == 0 { + // Find min element and place it in the first position of the array. We're free to use + // `unwrap()` here because we know v must not be empty. + let min_idx = min_index(v, is_less).unwrap(); + v.swap(min_idx, k); + return; + } + + let p = median_of_ninthers(v, is_less); + + if p == k { + return; + } else if p > k { + v = &mut v[..p]; + } else { + // Since `p < k < v.len()`, `p + 1` doesn't overflow and is + // a valid index into the slice. + v = &mut v[p + 1..]; + k -= p + 1; + } + } +} + +// Optimized for when `k` lies somewhere in the middle of the slice. Selects a pivot +// as close as possible to the median of the slice. For more details on how the algorithm +// operates, refer to the paper <https://drops.dagstuhl.de/opus/volltexte/2017/7612/pdf/LIPIcs-SEA-2017-24.pdf>. +fn median_of_ninthers<T, F: FnMut(&T, &T) -> bool>(v: &mut [T], is_less: &mut F) -> usize { + // use `saturating_mul` so the multiplication doesn't overflow on 16-bit platforms. + let frac = if v.len() <= 1024 { + v.len() / 12 + } else if v.len() <= 128_usize.saturating_mul(1024) { + v.len() / 64 + } else { + v.len() / 1024 + }; + + let pivot = frac / 2; + let lo = v.len() / 2 - pivot; + let hi = frac + lo; + let gap = (v.len() - 9 * frac) / 4; + let mut a = lo - 4 * frac - gap; + let mut b = hi + gap; + for i in lo..hi { + ninther(v, is_less, a, i - frac, b, a + 1, i, b + 1, a + 2, i + frac, b + 2); + a += 3; + b += 3; + } + + median_of_medians(&mut v[lo..lo + frac], is_less, pivot); + partition(v, lo + pivot, is_less).0 +} + +/// Moves around the 9 elements at the indices a..i, such that +/// `v[d]` contains the median of the 9 elements and the other +/// elements are partitioned around it. +fn ninther<T, F: FnMut(&T, &T) -> bool>( + v: &mut [T], + is_less: &mut F, + a: usize, + mut b: usize, + c: usize, + mut d: usize, + e: usize, + mut f: usize, + g: usize, + mut h: usize, + i: usize, +) { + b = median_idx(v, is_less, a, b, c); + h = median_idx(v, is_less, g, h, i); + if is_less(&v[h], &v[b]) { + mem::swap(&mut b, &mut h); + } + if is_less(&v[f], &v[d]) { + mem::swap(&mut d, &mut f); + } + if is_less(&v[e], &v[d]) { + // do nothing + } else if is_less(&v[f], &v[e]) { + d = f; + } else { + if is_less(&v[e], &v[b]) { + v.swap(e, b); + } else if is_less(&v[h], &v[e]) { + v.swap(e, h); + } + return; + } + if is_less(&v[d], &v[b]) { + d = b; + } else if is_less(&v[h], &v[d]) { + d = h; + } + + v.swap(d, e); +} + +/// returns the index pointing to the median of the 3 +/// elements `v[a]`, `v[b]` and `v[c]` +fn median_idx<T, F: FnMut(&T, &T) -> bool>( + v: &[T], + is_less: &mut F, + mut a: usize, + b: usize, + mut c: usize, +) -> usize { + if is_less(&v[c], &v[a]) { + mem::swap(&mut a, &mut c); + } + if is_less(&v[c], &v[b]) { + return c; + } + if is_less(&v[b], &v[a]) { + return a; + } + b +} diff --git a/library/core/src/slice/sort.rs b/library/core/src/slice/sort.rs index 07fd96f92..db76d2625 100644 --- a/library/core/src/slice/sort.rs +++ b/library/core/src/slice/sort.rs @@ -145,7 +145,7 @@ where /// Never inline this function to avoid code bloat. It still optimizes nicely and has practically no /// performance impact. Even improving performance in some cases. #[inline(never)] -fn insertion_sort_shift_left<T, F>(v: &mut [T], offset: usize, is_less: &mut F) +pub(super) fn insertion_sort_shift_left<T, F>(v: &mut [T], offset: usize, is_less: &mut F) where F: FnMut(&T, &T) -> bool, { @@ -557,7 +557,7 @@ where /// /// 1. Number of elements smaller than `v[pivot]`. /// 2. True if `v` was already partitioned. -fn partition<T, F>(v: &mut [T], pivot: usize, is_less: &mut F) -> (usize, bool) +pub(super) fn partition<T, F>(v: &mut [T], pivot: usize, is_less: &mut F) -> (usize, bool) where F: FnMut(&T, &T) -> bool, { @@ -612,7 +612,7 @@ where /// /// Returns the number of elements equal to the pivot. It is assumed that `v` does not contain /// elements smaller than the pivot. -fn partition_equal<T, F>(v: &mut [T], pivot: usize, is_less: &mut F) -> usize +pub(super) fn partition_equal<T, F>(v: &mut [T], pivot: usize, is_less: &mut F) -> usize where F: FnMut(&T, &T) -> bool, { @@ -670,7 +670,7 @@ where /// Scatters some elements around in an attempt to break patterns that might cause imbalanced /// partitions in quicksort. #[cold] -fn break_patterns<T>(v: &mut [T]) { +pub(super) fn break_patterns<T>(v: &mut [T]) { let len = v.len(); if len >= 8 { let mut seed = len; @@ -719,7 +719,7 @@ fn break_patterns<T>(v: &mut [T]) { /// Chooses a pivot in `v` and returns the index and `true` if the slice is likely already sorted. /// /// Elements in `v` might be reordered in the process. -fn choose_pivot<T, F>(v: &mut [T], is_less: &mut F) -> (usize, bool) +pub(super) fn choose_pivot<T, F>(v: &mut [T], is_less: &mut F) -> (usize, bool) where F: FnMut(&T, &T) -> bool, { @@ -897,138 +897,6 @@ where recurse(v, &mut is_less, None, limit); } -fn partition_at_index_loop<'a, T, F>( - mut v: &'a mut [T], - mut index: usize, - is_less: &mut F, - mut pred: Option<&'a T>, -) where - F: FnMut(&T, &T) -> bool, -{ - // Limit the amount of iterations and fall back to heapsort, similarly to `slice::sort_unstable`. - // This lowers the worst case running time from O(n^2) to O(n log n). - // FIXME: Investigate whether it would be better to use something like Median of Medians - // or Fast Deterministic Selection to guarantee O(n) worst case. - let mut limit = usize::BITS - v.len().leading_zeros(); - - // True if the last partitioning was reasonably balanced. - let mut was_balanced = true; - - loop { - let len = v.len(); - - // For slices of up to this length it's probably faster to simply sort them. - const MAX_INSERTION: usize = 10; - if len <= MAX_INSERTION { - if len >= 2 { - insertion_sort_shift_left(v, 1, is_less); - } - return; - } - - if limit == 0 { - heapsort(v, is_less); - return; - } - - // If the last partitioning was imbalanced, try breaking patterns in the slice by shuffling - // some elements around. Hopefully we'll choose a better pivot this time. - if !was_balanced { - break_patterns(v); - limit -= 1; - } - - // Choose a pivot - let (pivot, _) = choose_pivot(v, is_less); - - // If the chosen pivot is equal to the predecessor, then it's the smallest element in the - // slice. Partition the slice into elements equal to and elements greater than the pivot. - // This case is usually hit when the slice contains many duplicate elements. - if let Some(p) = pred { - if !is_less(p, &v[pivot]) { - let mid = partition_equal(v, pivot, is_less); - - // If we've passed our index, then we're good. - if mid > index { - return; - } - - // Otherwise, continue sorting elements greater than the pivot. - v = &mut v[mid..]; - index = index - mid; - pred = None; - continue; - } - } - - let (mid, _) = partition(v, pivot, is_less); - was_balanced = cmp::min(mid, len - mid) >= len / 8; - - // Split the slice into `left`, `pivot`, and `right`. - let (left, right) = v.split_at_mut(mid); - let (pivot, right) = right.split_at_mut(1); - let pivot = &pivot[0]; - - if mid < index { - v = right; - index = index - mid - 1; - pred = Some(pivot); - } else if mid > index { - v = left; - } else { - // If mid == index, then we're done, since partition() guaranteed that all elements - // after mid are greater than or equal to mid. - return; - } - } -} - -/// Reorder the slice such that the element at `index` is at its final sorted position. -pub fn partition_at_index<T, F>( - v: &mut [T], - index: usize, - mut is_less: F, -) -> (&mut [T], &mut T, &mut [T]) -where - F: FnMut(&T, &T) -> bool, -{ - use cmp::Ordering::Greater; - use cmp::Ordering::Less; - - if index >= v.len() { - panic!("partition_at_index index {} greater than length of slice {}", index, v.len()); - } - - if T::IS_ZST { - // Sorting has no meaningful behavior on zero-sized types. Do nothing. - } else if index == v.len() - 1 { - // Find max element and place it in the last position of the array. We're free to use - // `unwrap()` here because we know v must not be empty. - let (max_index, _) = v - .iter() - .enumerate() - .max_by(|&(_, x), &(_, y)| if is_less(x, y) { Less } else { Greater }) - .unwrap(); - v.swap(max_index, index); - } else if index == 0 { - // Find min element and place it in the first position of the array. We're free to use - // `unwrap()` here because we know v must not be empty. - let (min_index, _) = v - .iter() - .enumerate() - .min_by(|&(_, x), &(_, y)| if is_less(x, y) { Less } else { Greater }) - .unwrap(); - v.swap(min_index, index); - } else { - partition_at_index_loop(v, index, &mut is_less, None); - } - - let (left, right) = v.split_at_mut(index); - let (pivot, right) = right.split_at_mut(1); - let pivot = &mut pivot[0]; - (left, pivot, right) -} - /// Merges non-decreasing runs `v[..mid]` and `v[mid..]` using `buf` as temporary storage, and /// stores the result into `v[..]`. /// @@ -1085,12 +953,12 @@ where // SAFETY: left and right must be valid and part of v same for out. unsafe { - let to_copy = if is_less(&*right, &**left) { - get_and_increment(&mut right) - } else { - get_and_increment(left) - }; - ptr::copy_nonoverlapping(to_copy, get_and_increment(out), 1); + let is_l = is_less(&*right, &**left); + let to_copy = if is_l { right } else { *left }; + ptr::copy_nonoverlapping(to_copy, *out, 1); + *out = out.add(1); + right = right.add(is_l as usize); + *left = left.add(!is_l as usize); } } } else { @@ -1113,32 +981,18 @@ where // SAFETY: left and right must be valid and part of v same for out. unsafe { - let to_copy = if is_less(&*right.sub(1), &*left.sub(1)) { - decrement_and_get(left) - } else { - decrement_and_get(right) - }; - ptr::copy_nonoverlapping(to_copy, decrement_and_get(&mut out), 1); + let is_l = is_less(&*right.sub(1), &*left.sub(1)); + *left = left.sub(is_l as usize); + *right = right.sub(!is_l as usize); + let to_copy = if is_l { *left } else { *right }; + out = out.sub(1); + ptr::copy_nonoverlapping(to_copy, out, 1); } } } // Finally, `hole` gets dropped. If the shorter run was not fully consumed, whatever remains of // it will now be copied into the hole in `v`. - unsafe fn get_and_increment<T>(ptr: &mut *mut T) -> *mut T { - let old = *ptr; - - // SAFETY: ptr.add(1) must still be a valid pointer and part of `v`. - *ptr = unsafe { ptr.add(1) }; - old - } - - unsafe fn decrement_and_get<T>(ptr: &mut *mut T) -> *mut T { - // SAFETY: ptr.sub(1) must still be a valid pointer and part of `v`. - *ptr = unsafe { ptr.sub(1) }; - *ptr - } - // When dropped, copies the range `start..end` into `dest..`. struct MergeHole<T> { start: *mut T, @@ -1456,7 +1310,6 @@ pub struct TimSortRun { /// Takes a range as denoted by start and end, that is already sorted and extends it to the right if /// necessary with sorts optimized for smaller ranges such as insertion sort. -#[cfg(not(no_global_oom_handling))] fn provide_sorted_batch<T, F>(v: &mut [T], start: usize, mut end: usize, is_less: &mut F) -> usize where F: FnMut(&T, &T) -> bool, diff --git a/library/core/src/str/mod.rs b/library/core/src/str/mod.rs index 041694299..ef05b25fd 100644 --- a/library/core/src/str/mod.rs +++ b/library/core/src/str/mod.rs @@ -16,6 +16,7 @@ mod validations; use self::pattern::Pattern; use self::pattern::{DoubleEndedSearcher, ReverseSearcher, Searcher}; +use crate::ascii; use crate::char::{self, EscapeDebugExtArgs}; use crate::mem; use crate::slice::{self, SliceIndex}; @@ -206,9 +207,8 @@ impl str { /// ``` #[must_use] #[stable(feature = "is_char_boundary", since = "1.9.0")] - #[rustc_const_unstable(feature = "const_is_char_boundary", issue = "none")] #[inline] - pub const fn is_char_boundary(&self, index: usize) -> bool { + pub fn is_char_boundary(&self, index: usize) -> bool { // 0 is always ok. // Test for 0 explicitly so that it can optimize out the check // easily and skip reading string data for that case. @@ -436,9 +436,8 @@ impl str { /// assert!(v.get(..42).is_none()); /// ``` #[stable(feature = "str_checked_slicing", since = "1.20.0")] - #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] #[inline] - pub const fn get<I: ~const SliceIndex<str>>(&self, i: I) -> Option<&I::Output> { + pub fn get<I: SliceIndex<str>>(&self, i: I) -> Option<&I::Output> { i.get(self) } @@ -469,9 +468,8 @@ impl str { /// assert_eq!("HEllo", v); /// ``` #[stable(feature = "str_checked_slicing", since = "1.20.0")] - #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] #[inline] - pub const fn get_mut<I: ~const SliceIndex<str>>(&mut self, i: I) -> Option<&mut I::Output> { + pub fn get_mut<I: SliceIndex<str>>(&mut self, i: I) -> Option<&mut I::Output> { i.get_mut(self) } @@ -502,9 +500,8 @@ impl str { /// } /// ``` #[stable(feature = "str_checked_slicing", since = "1.20.0")] - #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] #[inline] - pub const unsafe fn get_unchecked<I: ~const SliceIndex<str>>(&self, i: I) -> &I::Output { + pub unsafe fn get_unchecked<I: SliceIndex<str>>(&self, i: I) -> &I::Output { // SAFETY: the caller must uphold the safety contract for `get_unchecked`; // the slice is dereferenceable because `self` is a safe reference. // The returned pointer is safe because impls of `SliceIndex` have to guarantee that it is. @@ -538,12 +535,8 @@ impl str { /// } /// ``` #[stable(feature = "str_checked_slicing", since = "1.20.0")] - #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] #[inline] - pub const unsafe fn get_unchecked_mut<I: ~const SliceIndex<str>>( - &mut self, - i: I, - ) -> &mut I::Output { + pub unsafe fn get_unchecked_mut<I: SliceIndex<str>>(&mut self, i: I) -> &mut I::Output { // SAFETY: the caller must uphold the safety contract for `get_unchecked_mut`; // the slice is dereferenceable because `self` is a safe reference. // The returned pointer is safe because impls of `SliceIndex` have to guarantee that it is. @@ -2365,15 +2358,26 @@ impl str { /// assert!(!non_ascii.is_ascii()); /// ``` #[stable(feature = "ascii_methods_on_intrinsics", since = "1.23.0")] + #[rustc_const_unstable(feature = "const_slice_is_ascii", issue = "111090")] #[must_use] #[inline] - pub fn is_ascii(&self) -> bool { + pub const fn is_ascii(&self) -> bool { // We can treat each byte as character here: all multibyte characters // start with a byte that is not in the ASCII range, so we will stop // there already. self.as_bytes().is_ascii() } + /// If this string slice [`is_ascii`](Self::is_ascii), returns it as a slice + /// of [ASCII characters](`ascii::Char`), otherwise returns `None`. + #[unstable(feature = "ascii_char", issue = "110998")] + #[must_use] + #[inline] + pub const fn as_ascii(&self) -> Option<&[ascii::Char]> { + // Like in `is_ascii`, we can work on the bytes directly. + self.as_bytes().as_ascii() + } + /// Checks that two strings are an ASCII case-insensitive match. /// /// Same as `to_ascii_lowercase(a) == to_ascii_lowercase(b)`, @@ -2582,8 +2586,7 @@ impl AsRef<[u8]> for str { } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] -impl const Default for &str { +impl Default for &str { /// Creates an empty str #[inline] fn default() -> Self { diff --git a/library/core/src/str/pattern.rs b/library/core/src/str/pattern.rs index e3a464a1c..91ee2903a 100644 --- a/library/core/src/str/pattern.rs +++ b/library/core/src/str/pattern.rs @@ -791,8 +791,8 @@ pub struct CharArrayRefSearcher<'a, 'b, const N: usize>( /// # Examples /// /// ``` -/// assert_eq!("Hello world".find(['l', 'l']), Some(2)); -/// assert_eq!("Hello world".find(['l', 'l']), Some(2)); +/// assert_eq!("Hello world".find(['o', 'l']), Some(2)); +/// assert_eq!("Hello world".find(['h', 'w']), Some(6)); /// ``` impl<'a, const N: usize> Pattern<'a> for [char; N] { pattern_methods!(CharArraySearcher<'a, N>, MultiCharEqPattern, CharArraySearcher); @@ -811,8 +811,8 @@ unsafe impl<'a, const N: usize> ReverseSearcher<'a> for CharArraySearcher<'a, N> /// # Examples /// /// ``` -/// assert_eq!("Hello world".find(&['l', 'l']), Some(2)); -/// assert_eq!("Hello world".find(&['l', 'l']), Some(2)); +/// assert_eq!("Hello world".find(&['o', 'l']), Some(2)); +/// assert_eq!("Hello world".find(&['h', 'w']), Some(6)); /// ``` impl<'a, 'b, const N: usize> Pattern<'a> for &'b [char; N] { pattern_methods!(CharArrayRefSearcher<'a, 'b, N>, MultiCharEqPattern, CharArrayRefSearcher); diff --git a/library/core/src/str/traits.rs b/library/core/src/str/traits.rs index 41c097b55..1d52335f2 100644 --- a/library/core/src/str/traits.rs +++ b/library/core/src/str/traits.rs @@ -50,10 +50,9 @@ impl PartialOrd for str { } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -impl<I> const ops::Index<I> for str +impl<I> ops::Index<I> for str where - I: ~const SliceIndex<str>, + I: SliceIndex<str>, { type Output = I::Output; @@ -64,10 +63,9 @@ where } #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -impl<I> const ops::IndexMut<I> for str +impl<I> ops::IndexMut<I> for str where - I: ~const SliceIndex<str>, + I: SliceIndex<str>, { #[inline] fn index_mut(&mut self, index: I) -> &mut I::Output { @@ -96,7 +94,7 @@ const fn str_index_overflow_fail() -> ! { /// Equivalent to `&self[0 .. len]` or `&mut self[0 .. len]`. #[stable(feature = "str_checked_slicing", since = "1.20.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl const SliceIndex<str> for ops::RangeFull { +unsafe impl SliceIndex<str> for ops::RangeFull { type Output = str; #[inline] fn get(self, slice: &str) -> Option<&Self::Output> { @@ -161,7 +159,7 @@ unsafe impl const SliceIndex<str> for ops::RangeFull { /// ``` #[stable(feature = "str_checked_slicing", since = "1.20.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl const SliceIndex<str> for ops::Range<usize> { +unsafe impl SliceIndex<str> for ops::Range<usize> { type Output = str; #[inline] fn get(self, slice: &str) -> Option<&Self::Output> { @@ -271,7 +269,7 @@ unsafe impl const SliceIndex<str> for ops::Range<usize> { /// character (as defined by `is_char_boundary`), or if `end > len`. #[stable(feature = "str_checked_slicing", since = "1.20.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl const SliceIndex<str> for ops::RangeTo<usize> { +unsafe impl SliceIndex<str> for ops::RangeTo<usize> { type Output = str; #[inline] fn get(self, slice: &str) -> Option<&Self::Output> { @@ -340,7 +338,7 @@ unsafe impl const SliceIndex<str> for ops::RangeTo<usize> { /// a character (as defined by `is_char_boundary`), or if `begin > len`. #[stable(feature = "str_checked_slicing", since = "1.20.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl const SliceIndex<str> for ops::RangeFrom<usize> { +unsafe impl SliceIndex<str> for ops::RangeFrom<usize> { type Output = str; #[inline] fn get(self, slice: &str) -> Option<&Self::Output> { @@ -412,7 +410,7 @@ unsafe impl const SliceIndex<str> for ops::RangeFrom<usize> { /// byte offset or equal to `len`), if `begin > end`, or if `end >= len`. #[stable(feature = "inclusive_range", since = "1.26.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl const SliceIndex<str> for ops::RangeInclusive<usize> { +unsafe impl SliceIndex<str> for ops::RangeInclusive<usize> { type Output = str; #[inline] fn get(self, slice: &str) -> Option<&Self::Output> { @@ -464,7 +462,7 @@ unsafe impl const SliceIndex<str> for ops::RangeInclusive<usize> { /// `is_char_boundary`, or equal to `len`), or if `end >= len`. #[stable(feature = "inclusive_range", since = "1.26.0")] #[rustc_const_unstable(feature = "const_slice_index", issue = "none")] -unsafe impl const SliceIndex<str> for ops::RangeToInclusive<usize> { +unsafe impl SliceIndex<str> for ops::RangeToInclusive<usize> { type Output = str; #[inline] fn get(self, slice: &str) -> Option<&Self::Output> { diff --git a/library/core/src/sync/atomic.rs b/library/core/src/sync/atomic.rs index f1ed68d72..236b7f423 100644 --- a/library/core/src/sync/atomic.rs +++ b/library/core/src/sync/atomic.rs @@ -147,8 +147,7 @@ pub struct AtomicBool { #[cfg(target_has_atomic_load_store = "8")] #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] -impl const Default for AtomicBool { +impl Default for AtomicBool { /// Creates an `AtomicBool` initialized to `false`. #[inline] fn default() -> Self { @@ -179,8 +178,7 @@ pub struct AtomicPtr<T> { #[cfg(target_has_atomic_load_store = "ptr")] #[stable(feature = "rust1", since = "1.0.0")] -#[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] -impl<T> const Default for AtomicPtr<T> { +impl<T> Default for AtomicPtr<T> { /// Creates a null `AtomicPtr<T>`. fn default() -> AtomicPtr<T> { AtomicPtr::new(crate::ptr::null_mut()) @@ -1916,8 +1914,7 @@ impl<T> AtomicPtr<T> { #[cfg(target_has_atomic_load_store = "8")] #[stable(feature = "atomic_bool_from", since = "1.24.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl const From<bool> for AtomicBool { +impl From<bool> for AtomicBool { /// Converts a `bool` into an `AtomicBool`. /// /// # Examples @@ -1935,8 +1932,7 @@ impl const From<bool> for AtomicBool { #[cfg(target_has_atomic_load_store = "ptr")] #[stable(feature = "atomic_from", since = "1.23.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T> const From<*mut T> for AtomicPtr<T> { +impl<T> From<*mut T> for AtomicPtr<T> { /// Converts a `*mut T` into an `AtomicPtr<T>`. #[inline] fn from(p: *mut T) -> Self { @@ -2002,8 +1998,7 @@ macro_rules! atomic_int { pub const $atomic_init: $atomic_type = $atomic_type::new(0); #[$stable] - #[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] - impl const Default for $atomic_type { + impl Default for $atomic_type { #[inline] fn default() -> Self { Self::new(Default::default()) @@ -2011,8 +2006,7 @@ macro_rules! atomic_int { } #[$stable_from] - #[rustc_const_unstable(feature = "const_num_from_num", issue = "87852")] - impl const From<$int_type> for $atomic_type { + impl From<$int_type> for $atomic_type { #[doc = concat!("Converts an `", stringify!($int_type), "` into an `", stringify!($atomic_type), "`.")] #[inline] fn from(v: $int_type) -> Self { Self::new(v) } diff --git a/library/core/src/task/mod.rs b/library/core/src/task/mod.rs index c5f89b9a2..3f0080e38 100644 --- a/library/core/src/task/mod.rs +++ b/library/core/src/task/mod.rs @@ -13,5 +13,3 @@ pub use self::wake::{Context, RawWaker, RawWakerVTable, Waker}; mod ready; #[stable(feature = "ready_macro", since = "1.64.0")] pub use ready::ready; -#[unstable(feature = "poll_ready", issue = "89780")] -pub use ready::Ready; diff --git a/library/core/src/task/poll.rs b/library/core/src/task/poll.rs index af5bf441b..0a0f702f6 100644 --- a/library/core/src/task/poll.rs +++ b/library/core/src/task/poll.rs @@ -3,7 +3,6 @@ use crate::convert; use crate::ops::{self, ControlFlow}; use crate::result::Result; -use crate::task::Ready; /// Indicates whether a value is available or if the current task has been /// scheduled to receive a wakeup instead. @@ -95,38 +94,6 @@ impl<T> Poll<T> { pub const fn is_pending(&self) -> bool { !self.is_ready() } - - /// Extracts the successful type of a [`Poll<T>`]. - /// - /// When combined with the `?` operator, this function will - /// propagate any [`Poll::Pending`] values to the caller, and - /// extract the `T` from [`Poll::Ready`]. - /// - /// # Examples - /// - /// ```rust - /// #![feature(poll_ready)] - /// - /// use std::task::{Context, Poll}; - /// use std::future::{self, Future}; - /// use std::pin::Pin; - /// - /// pub fn do_poll(cx: &mut Context<'_>) -> Poll<()> { - /// let mut fut = future::ready(42); - /// let fut = Pin::new(&mut fut); - /// - /// let num = fut.poll(cx).ready()?; - /// # drop(num); - /// // ... use num - /// - /// Poll::Ready(()) - /// } - /// ``` - #[inline] - #[unstable(feature = "poll_ready", issue = "89780")] - pub fn ready(self) -> Ready<T> { - Ready(self) - } } impl<T, E> Poll<Result<T, E>> { @@ -247,8 +214,7 @@ impl<T, E> Poll<Option<Result<T, E>>> { } #[stable(feature = "futures_api", since = "1.36.0")] -#[rustc_const_unstable(feature = "const_convert", issue = "88674")] -impl<T> const From<T> for Poll<T> { +impl<T> From<T> for Poll<T> { /// Moves the value into a [`Poll::Ready`] to make a `Poll<T>`. /// /// # Example diff --git a/library/core/src/task/ready.rs b/library/core/src/task/ready.rs index b1daf545f..495d72fd1 100644 --- a/library/core/src/task/ready.rs +++ b/library/core/src/task/ready.rs @@ -1,8 +1,3 @@ -use core::convert; -use core::fmt; -use core::ops::{ControlFlow, FromResidual, Try}; -use core::task::Poll; - /// Extracts the successful type of a [`Poll<T>`]. /// /// This macro bakes in propagation of [`Pending`] signals by returning early. @@ -22,7 +17,7 @@ use core::task::Poll; /// let fut = Pin::new(&mut fut); /// /// let num = ready!(fut.poll(cx)); -/// # drop(num); +/// # let _ = num; /// // ... use num /// /// Poll::Ready(()) @@ -44,7 +39,7 @@ use core::task::Poll; /// Poll::Ready(t) => t, /// Poll::Pending => return Poll::Pending, /// }; -/// # drop(num); +/// # let _ = num; // to silence unused warning /// # // ... use num /// # /// # Poll::Ready(()) @@ -60,55 +55,3 @@ pub macro ready($e:expr) { } } } - -/// Extracts the successful type of a [`Poll<T>`]. -/// -/// See [`Poll::ready`] for details. -#[unstable(feature = "poll_ready", issue = "89780")] -pub struct Ready<T>(pub(crate) Poll<T>); - -#[unstable(feature = "poll_ready", issue = "89780")] -impl<T> Try for Ready<T> { - type Output = T; - type Residual = Ready<convert::Infallible>; - - #[inline] - fn from_output(output: Self::Output) -> Self { - Ready(Poll::Ready(output)) - } - - #[inline] - fn branch(self) -> ControlFlow<Self::Residual, Self::Output> { - match self.0 { - Poll::Ready(v) => ControlFlow::Continue(v), - Poll::Pending => ControlFlow::Break(Ready(Poll::Pending)), - } - } -} - -#[unstable(feature = "poll_ready", issue = "89780")] -impl<T> FromResidual for Ready<T> { - #[inline] - fn from_residual(residual: Ready<convert::Infallible>) -> Self { - match residual.0 { - Poll::Pending => Ready(Poll::Pending), - } - } -} - -#[unstable(feature = "poll_ready", issue = "89780")] -impl<T> FromResidual<Ready<convert::Infallible>> for Poll<T> { - #[inline] - fn from_residual(residual: Ready<convert::Infallible>) -> Self { - match residual.0 { - Poll::Pending => Poll::Pending, - } - } -} - -#[unstable(feature = "poll_ready", issue = "89780")] -impl<T> fmt::Debug for Ready<T> { - fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { - f.debug_tuple("Ready").finish() - } -} diff --git a/library/core/src/task/wake.rs b/library/core/src/task/wake.rs index 808825326..7043ab5ff 100644 --- a/library/core/src/task/wake.rs +++ b/library/core/src/task/wake.rs @@ -232,7 +232,7 @@ impl fmt::Debug for Context<'_> { /// /// [`Future::poll()`]: core::future::Future::poll /// [`Poll::Pending`]: core::task::Poll::Pending -#[repr(transparent)] +#[cfg_attr(not(doc), repr(transparent))] // work around https://github.com/rust-lang/rust/issues/66401 #[stable(feature = "futures_api", since = "1.36.0")] pub struct Waker { waker: RawWaker, diff --git a/library/core/src/time.rs b/library/core/src/time.rs index ba1cb6efa..b08d5782a 100644 --- a/library/core/src/time.rs +++ b/library/core/src/time.rs @@ -735,8 +735,7 @@ impl Duration { #[stable(feature = "duration_float", since = "1.38.0")] #[must_use] #[inline] - #[rustc_const_unstable(feature = "duration_consts_float", issue = "72440")] - pub const fn from_secs_f64(secs: f64) -> Duration { + pub fn from_secs_f64(secs: f64) -> Duration { match Duration::try_from_secs_f64(secs) { Ok(v) => v, Err(e) => panic!("{}", e.description()), @@ -773,8 +772,7 @@ impl Duration { #[stable(feature = "duration_float", since = "1.38.0")] #[must_use] #[inline] - #[rustc_const_unstable(feature = "duration_consts_float", issue = "72440")] - pub const fn from_secs_f32(secs: f32) -> Duration { + pub fn from_secs_f32(secs: f32) -> Duration { match Duration::try_from_secs_f32(secs) { Ok(v) => v, Err(e) => panic!("{}", e.description()), @@ -798,8 +796,7 @@ impl Duration { #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] - #[rustc_const_unstable(feature = "duration_consts_float", issue = "72440")] - pub const fn mul_f64(self, rhs: f64) -> Duration { + pub fn mul_f64(self, rhs: f64) -> Duration { Duration::from_secs_f64(rhs * self.as_secs_f64()) } @@ -820,8 +817,7 @@ impl Duration { #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] - #[rustc_const_unstable(feature = "duration_consts_float", issue = "72440")] - pub const fn mul_f32(self, rhs: f32) -> Duration { + pub fn mul_f32(self, rhs: f32) -> Duration { Duration::from_secs_f32(rhs * self.as_secs_f32()) } @@ -842,8 +838,7 @@ impl Duration { #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] - #[rustc_const_unstable(feature = "duration_consts_float", issue = "72440")] - pub const fn div_f64(self, rhs: f64) -> Duration { + pub fn div_f64(self, rhs: f64) -> Duration { Duration::from_secs_f64(self.as_secs_f64() / rhs) } @@ -866,8 +861,7 @@ impl Duration { #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] - #[rustc_const_unstable(feature = "duration_consts_float", issue = "72440")] - pub const fn div_f32(self, rhs: f32) -> Duration { + pub fn div_f32(self, rhs: f32) -> Duration { Duration::from_secs_f32(self.as_secs_f32() / rhs) } @@ -1178,7 +1172,7 @@ impl fmt::Debug for Duration { emit_without_padding(f) } else { // We need to add padding. Use the `Formatter::padding` helper function. - let default_align = crate::fmt::rt::v1::Alignment::Left; + let default_align = fmt::Alignment::Left; let post_padding = f.padding(requested_w - actual_w, default_align)?; emit_without_padding(f)?; post_padding.write(f) @@ -1402,9 +1396,8 @@ impl Duration { /// assert_eq!(res, Ok(Duration::new(1, 2_929_688))); /// ``` #[stable(feature = "duration_checked_float", since = "1.66.0")] - #[rustc_const_unstable(feature = "duration_consts_float", issue = "72440")] #[inline] - pub const fn try_from_secs_f32(secs: f32) -> Result<Duration, TryFromFloatSecsError> { + pub fn try_from_secs_f32(secs: f32) -> Result<Duration, TryFromFloatSecsError> { try_from_secs!( secs = secs, mantissa_bits = 23, @@ -1479,9 +1472,8 @@ impl Duration { /// assert_eq!(res, Ok(Duration::new(1, 2_929_688))); /// ``` #[stable(feature = "duration_checked_float", since = "1.66.0")] - #[rustc_const_unstable(feature = "duration_consts_float", issue = "72440")] #[inline] - pub const fn try_from_secs_f64(secs: f64) -> Result<Duration, TryFromFloatSecsError> { + pub fn try_from_secs_f64(secs: f64) -> Result<Duration, TryFromFloatSecsError> { try_from_secs!( secs = secs, mantissa_bits = 52, diff --git a/library/core/src/tuple.rs b/library/core/src/tuple.rs index 0620e7173..a1388dfee 100644 --- a/library/core/src/tuple.rs +++ b/library/core/src/tuple.rs @@ -1,7 +1,6 @@ // See src/libstd/primitive_docs.rs for documentation. use crate::cmp::Ordering::{self, *}; -use crate::mem::transmute; // Recursive macro for implementing n-ary tuple functions and operations // @@ -22,8 +21,7 @@ macro_rules! tuple_impls { maybe_tuple_doc! { $($T)+ @ #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl<$($T: ~const PartialEq),+> const PartialEq for ($($T,)+) + impl<$($T: PartialEq),+> PartialEq for ($($T,)+) where last_type!($($T,)+): ?Sized { @@ -50,8 +48,7 @@ macro_rules! tuple_impls { maybe_tuple_doc! { $($T)+ @ #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl<$($T: ~const PartialOrd + ~const PartialEq),+> const PartialOrd for ($($T,)+) + impl<$($T: PartialOrd),+> PartialOrd for ($($T,)+) where last_type!($($T,)+): ?Sized { @@ -81,8 +78,7 @@ macro_rules! tuple_impls { maybe_tuple_doc! { $($T)+ @ #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_cmp", issue = "92391")] - impl<$($T: ~const Ord),+> const Ord for ($($T,)+) + impl<$($T: Ord),+> Ord for ($($T,)+) where last_type!($($T,)+): ?Sized { @@ -96,14 +92,33 @@ macro_rules! tuple_impls { maybe_tuple_doc! { $($T)+ @ #[stable(feature = "rust1", since = "1.0.0")] - #[rustc_const_unstable(feature = "const_default_impls", issue = "87864")] - impl<$($T: ~const Default),+> const Default for ($($T,)+) { + impl<$($T: Default),+> Default for ($($T,)+) { #[inline] fn default() -> ($($T,)+) { ($({ let x: $T = Default::default(); x},)+) } } } + + #[stable(feature = "array_tuple_conv", since = "1.71.0")] + impl<T> From<[T; ${count(T)}]> for ($(${ignore(T)} T,)+) { + #[inline] + #[allow(non_snake_case)] + fn from(array: [T; ${count(T)}]) -> Self { + let [$($T,)+] = array; + ($($T,)+) + } + } + + #[stable(feature = "array_tuple_conv", since = "1.71.0")] + impl<T> From<($(${ignore(T)} T,)+)> for [T; ${count(T)}] { + #[inline] + #[allow(non_snake_case)] + fn from(tuple: ($(${ignore(T)} T,)+)) -> Self { + let ($($T,)+) = tuple; + [$($T,)+] + } + } } } @@ -126,16 +141,13 @@ macro_rules! maybe_tuple_doc { #[inline] const fn ordering_is_some(c: Option<Ordering>, x: Ordering) -> bool { // FIXME: Just use `==` once that's const-stable on `Option`s. - // This isn't using `match` because that optimizes worse due to - // making a two-step check (`Some` *then* the inner value). - - // SAFETY: There's no public guarantee for `Option<Ordering>`, - // but we're core so we know that it's definitely a byte. - unsafe { - let c: i8 = transmute(c); - let x: i8 = transmute(Some(x)); - c == x - } + // This is mapping `None` to 2 and then doing the comparison afterwards + // because it optimizes better (`None::<Ordering>` is represented as 2). + x as i8 + == match c { + Some(c) => c as i8, + None => 2, + } } // Constructs an expression that performs a lexical ordering using method `$rel`. diff --git a/library/core/tests/asserting.rs b/library/core/tests/asserting.rs index 4b626ba6f..1d9670886 100644 --- a/library/core/tests/asserting.rs +++ b/library/core/tests/asserting.rs @@ -24,7 +24,7 @@ struct NoCopyNoDebug; struct NoDebug; test!( - capture_with_non_copyable_and_non_debugabble_elem_has_correct_params, + capture_with_non_copyable_and_non_debuggable_elem_has_correct_params, NoCopyNoDebug, None, "N/A" @@ -32,6 +32,6 @@ test!( test!(capture_with_non_copyable_elem_has_correct_params, NoCopy, None, "N/A"); -test!(capture_with_non_debugabble_elem_has_correct_params, NoDebug, None, "N/A"); +test!(capture_with_non_debuggable_elem_has_correct_params, NoDebug, None, "N/A"); -test!(capture_with_copyable_and_debugabble_elem_has_correct_params, 1i32, Some(1i32), "1"); +test!(capture_with_copyable_and_debuggable_elem_has_correct_params, 1i32, Some(1i32), "1"); diff --git a/library/core/tests/atomic.rs b/library/core/tests/atomic.rs index 94b031060..a67a842d3 100644 --- a/library/core/tests/atomic.rs +++ b/library/core/tests/atomic.rs @@ -306,9 +306,11 @@ fn atomic_compare_exchange() { ATOMIC.compare_exchange_weak(0, 1, SeqCst, SeqCst).ok(); } +/* FIXME(#110395) #[test] fn atomic_const_from() { const _ATOMIC_U8: AtomicU8 = AtomicU8::from(1); const _ATOMIC_BOOL: AtomicBool = AtomicBool::from(true); const _ATOMIC_PTR: AtomicPtr<u32> = AtomicPtr::from(core::ptr::null_mut()); } +*/ diff --git a/library/core/tests/bool.rs b/library/core/tests/bool.rs index 4819ce911..47f645991 100644 --- a/library/core/tests/bool.rs +++ b/library/core/tests/bool.rs @@ -89,6 +89,7 @@ fn test_bool_to_option() { assert_eq!(false.then(|| 0), None); assert_eq!(true.then(|| 0), Some(0)); + /* FIXME(#110395) const fn zero() -> i32 { 0 } @@ -102,4 +103,5 @@ fn test_bool_to_option() { assert_eq!(B, Some(0)); assert_eq!(C, None); assert_eq!(D, Some(0)); + */ } diff --git a/library/core/tests/cell.rs b/library/core/tests/cell.rs index 7b77b2134..e084f8679 100644 --- a/library/core/tests/cell.rs +++ b/library/core/tests/cell.rs @@ -468,6 +468,7 @@ fn const_cells() { const CELL: Cell<i32> = Cell::new(3); const _: i32 = CELL.into_inner(); +/* FIXME(#110395) const UNSAFE_CELL_FROM: UnsafeCell<i32> = UnsafeCell::from(3); const _: i32 = UNSAFE_CELL.into_inner(); @@ -476,4 +477,5 @@ fn const_cells() { const CELL_FROM: Cell<i32> = Cell::from(3); const _: i32 = CELL.into_inner(); +*/ } diff --git a/library/core/tests/char.rs b/library/core/tests/char.rs index ac0b2ca16..85ba51c92 100644 --- a/library/core/tests/char.rs +++ b/library/core/tests/char.rs @@ -21,6 +21,7 @@ fn test_convert() { assert!(char::try_from(0xFFFF_FFFF_u32).is_err()); } +/* FIXME(#110395) #[test] const fn test_convert_const() { assert!(u32::from('a') == 0x61); @@ -30,6 +31,7 @@ const fn test_convert_const() { assert!(char::from(b'a') == 'a'); assert!(char::from(b'\xFF') == '\u{FF}'); } +*/ #[test] fn test_from_str() { diff --git a/library/core/tests/clone.rs b/library/core/tests/clone.rs index 33ca9f2c6..aafe5ced2 100644 --- a/library/core/tests/clone.rs +++ b/library/core/tests/clone.rs @@ -1,4 +1,5 @@ #[test] +#[cfg_attr(not(bootstrap), allow(suspicious_double_ref_op))] fn test_borrowed_clone() { let x = 5; let y: &i32 = &x; diff --git a/library/core/tests/cmp.rs b/library/core/tests/cmp.rs index 8d0e59d5a..72fdd490d 100644 --- a/library/core/tests/cmp.rs +++ b/library/core/tests/cmp.rs @@ -217,18 +217,19 @@ fn cmp_default() { assert_eq!(Fool(false), Fool(true)); } +/* FIXME(#110395) mod const_cmp { use super::*; struct S(i32); - impl const PartialEq for S { + impl PartialEq for S { fn eq(&self, other: &Self) -> bool { self.0 == other.0 } } - impl const PartialOrd for S { + impl PartialOrd for S { fn partial_cmp(&self, other: &Self) -> Option<Ordering> { let ret = match (self.0, other.0) { (a, b) if a > b => Ordering::Greater, @@ -248,3 +249,4 @@ mod const_cmp { const _: () = assert!(S(0) < S(1)); const _: () = assert!(S(1) > S(0)); } +*/ diff --git a/library/core/tests/convert.rs b/library/core/tests/convert.rs index f1048f4cf..f76dd2778 100644 --- a/library/core/tests/convert.rs +++ b/library/core/tests/convert.rs @@ -1,3 +1,4 @@ +/* FIXME(#110395) #[test] fn convert() { const fn from(x: i32) -> i32 { @@ -14,3 +15,4 @@ fn convert() { const BAR: Vec<String> = into(Vec::new()); assert_eq!(BAR, Vec::<String>::new()); } +*/ diff --git a/library/core/tests/hash/mod.rs b/library/core/tests/hash/mod.rs index 267245f05..033bd1ed6 100644 --- a/library/core/tests/hash/mod.rs +++ b/library/core/tests/hash/mod.rs @@ -9,13 +9,13 @@ struct MyHasher { hash: u64, } -impl const Default for MyHasher { +impl Default for MyHasher { fn default() -> MyHasher { MyHasher { hash: 0 } } } -impl const Hasher for MyHasher { +impl Hasher for MyHasher { fn write(&mut self, buf: &[u8]) { // FIXME(const_trait_impl): change to for loop let mut i = 0; @@ -35,13 +35,14 @@ impl const Hasher for MyHasher { #[test] fn test_writer_hasher() { - const fn hash<T: ~const Hash>(t: &T) -> u64 { + // FIXME(#110395) + /* const */ fn hash<T: Hash>(t: &T) -> u64 { let mut s = MyHasher { hash: 0 }; t.hash(&mut s); s.finish() } - const { + /* const { // FIXME(fee1-dead): assert_eq assert!(hash(&()) == 0); assert!(hash(&5_u8) == 5); @@ -52,7 +53,7 @@ fn test_writer_hasher() { let s: &str = "a"; assert!(hash(&s) == 97 + 0xFF); - }; + }; */ assert_eq!(hash(&()), 0); @@ -113,7 +114,7 @@ struct CustomHasher { output: u64, } -impl const Hasher for CustomHasher { +impl Hasher for CustomHasher { fn finish(&self) -> u64 { self.output } @@ -125,21 +126,22 @@ impl const Hasher for CustomHasher { } } -impl const Default for CustomHasher { +impl Default for CustomHasher { fn default() -> CustomHasher { CustomHasher { output: 0 } } } -impl const Hash for Custom { - fn hash<H: ~const Hasher>(&self, state: &mut H) { +impl Hash for Custom { + fn hash<H: Hasher>(&self, state: &mut H) { state.write_u64(self.hash); } } #[test] fn test_custom_state() { - const fn hash<T: ~const Hash>(t: &T) -> u64 { + // FIXME(#110395) + /* const */ fn hash<T: Hash>(t: &T) -> u64 { let mut c = CustomHasher { output: 0 }; t.hash(&mut c); c.finish() @@ -147,7 +149,7 @@ fn test_custom_state() { assert_eq!(hash(&Custom { hash: 5 }), 5); - const { assert!(hash(&Custom { hash: 6 }) == 6) }; + // const { assert!(hash(&Custom { hash: 6 }) == 6) }; } // FIXME: Instantiated functions with i128 in the signature is not supported in Emscripten. diff --git a/library/core/tests/hash/sip.rs b/library/core/tests/hash/sip.rs index 3abf6efcf..0a67c485c 100644 --- a/library/core/tests/hash/sip.rs +++ b/library/core/tests/hash/sip.rs @@ -23,12 +23,13 @@ fn hash<T: Hash>(x: &T) -> u64 { hash_with(SipHasher::new(), x) } +/* FIXME(#110395) #[test] const fn test_const_sip() { let val1 = 0x45; let val2 = 0xfeed; - const fn const_hash<T: ~const Hash>(x: &T) -> u64 { + const fn const_hash<T: Hash>(x: &T) -> u64 { let mut st = SipHasher::new(); x.hash(&mut st); st.finish() @@ -36,6 +37,7 @@ const fn test_const_sip() { assert!(const_hash(&(val1)) != const_hash(&(val2))); } +*/ #[test] #[allow(unused_must_use)] diff --git a/library/core/tests/lazy.rs b/library/core/tests/lazy.rs index c7c3c479b..7f7f1f005 100644 --- a/library/core/tests/lazy.rs +++ b/library/core/tests/lazy.rs @@ -10,7 +10,7 @@ fn once_cell() { c.get_or_init(|| 92); assert_eq!(c.get(), Some(&92)); - c.get_or_init(|| panic!("Kabom!")); + c.get_or_init(|| panic!("Kaboom!")); assert_eq!(c.get(), Some(&92)); } @@ -46,11 +46,13 @@ fn unsync_once_cell_drop_empty() { drop(x); } +/* FIXME(#110395) #[test] const fn once_cell_const() { let _once_cell: OnceCell<u32> = OnceCell::new(); let _once_cell: OnceCell<u32> = OnceCell::from(32); } +*/ #[test] fn clone() { diff --git a/library/core/tests/lib.rs b/library/core/tests/lib.rs index 6cdafa411..3933e3289 100644 --- a/library/core/tests/lib.rs +++ b/library/core/tests/lib.rs @@ -8,20 +8,16 @@ #![feature(const_assume)] #![feature(const_align_of_val_raw)] #![feature(const_black_box)] -#![feature(const_bool_to_option)] #![feature(const_caller_location)] #![feature(const_cell_into_inner)] -#![feature(const_convert)] #![feature(const_hash)] #![feature(const_heap)] #![feature(const_maybe_uninit_as_mut_ptr)] #![feature(const_maybe_uninit_assume_init_read)] #![feature(const_nonnull_new)] -#![feature(const_num_from_num)] #![feature(const_pointer_byte_offsets)] #![feature(const_pointer_is_aligned)] #![feature(const_ptr_as_ref)] -#![feature(const_ptr_read)] #![feature(const_ptr_write)] #![feature(const_trait_impl)] #![feature(const_likely)] @@ -57,6 +53,7 @@ #![feature(maybe_uninit_uninit_array_transpose)] #![feature(min_specialization)] #![feature(numfmt)] +#![feature(num_midpoint)] #![feature(step_trait)] #![feature(str_internals)] #![feature(std_internals)] @@ -112,6 +109,7 @@ #![feature(utf8_chunks)] #![feature(is_ascii_octdigit)] #![feature(get_many_mut)] +#![cfg_attr(not(bootstrap), feature(offset_of))] #![deny(unsafe_op_in_unsafe_fn)] #![deny(fuzzy_provenance_casts)] diff --git a/library/core/tests/mem.rs b/library/core/tests/mem.rs index f7740a114..aee9c89b5 100644 --- a/library/core/tests/mem.rs +++ b/library/core/tests/mem.rs @@ -364,3 +364,213 @@ fn const_maybe_uninit() { assert_eq!(FIELD_BY_FIELD, Foo { x: 1, y: 2 }); } + +#[test] +#[cfg(not(bootstrap))] +fn offset_of() { + #[repr(C)] + struct Foo { + x: u8, + y: u16, + z: Bar, + } + + #[repr(C)] + struct Bar(u8, u8); + + assert_eq!(offset_of!(Foo, x), 0); + assert_eq!(offset_of!(Foo, y), 2); + assert_eq!(offset_of!(Foo, z.0), 4); + assert_eq!(offset_of!(Foo, z.1), 5); + + // Layout of tuples is unstable + assert!(offset_of!((u8, u16), 0) <= size_of::<(u8, u16)>() - 1); + assert!(offset_of!((u8, u16), 1) <= size_of::<(u8, u16)>() - 2); + + #[repr(C)] + struct Generic<T> { + x: u8, + y: u32, + z: T + } + + trait Trait {} + + // Ensure that this type of generics works + fn offs_of_z<T>() -> usize { + offset_of!(Generic<T>, z) + } + + assert_eq!(offset_of!(Generic<u8>, z), 8); + assert_eq!(offs_of_z::<u8>(), 8); + + // Ensure that it works with the implicit lifetime in `Box<dyn Trait + '_>`. + assert_eq!(offset_of!(Generic<Box<dyn Trait>>, z), 8); +} + +#[test] +#[cfg(not(bootstrap))] +fn offset_of_union() { + #[repr(C)] + union Foo { + x: u8, + y: u16, + z: Bar, + } + + #[repr(C)] + #[derive(Copy, Clone)] + struct Bar(u8, u8); + + assert_eq!(offset_of!(Foo, x), 0); + assert_eq!(offset_of!(Foo, y), 0); + assert_eq!(offset_of!(Foo, z.0), 0); + assert_eq!(offset_of!(Foo, z.1), 1); +} + +#[test] +#[cfg(not(bootstrap))] +fn offset_of_dst() { + #[repr(C)] + struct Alpha { + x: u8, + y: u16, + z: [u8], + } + + trait Trait {} + + #[repr(C)] + struct Beta { + x: u8, + y: u16, + z: dyn Trait, + } + + extern "C" { + type Extern; + } + + #[repr(C)] + struct Gamma { + x: u8, + y: u16, + z: Extern, + } + + assert_eq!(offset_of!(Alpha, x), 0); + assert_eq!(offset_of!(Alpha, y), 2); + + assert_eq!(offset_of!(Beta, x), 0); + assert_eq!(offset_of!(Beta, y), 2); + + assert_eq!(offset_of!(Gamma, x), 0); + assert_eq!(offset_of!(Gamma, y), 2); +} + +#[test] +#[cfg(not(bootstrap))] +fn offset_of_packed() { + #[repr(C, packed)] + struct Foo { + x: u8, + y: u16, + } + + assert_eq!(offset_of!(Foo, x), 0); + assert_eq!(offset_of!(Foo, y), 1); +} + +#[test] +#[cfg(not(bootstrap))] +fn offset_of_projection() { + #[repr(C)] + struct Foo { + x: u8, + y: u16, + } + + trait Projector { + type Type; + } + + impl Projector for () { + type Type = Foo; + } + + assert_eq!(offset_of!(<() as Projector>::Type, x), 0); + assert_eq!(offset_of!(<() as Projector>::Type, y), 2); +} + +#[test] +#[cfg(not(bootstrap))] +fn offset_of_alias() { + #[repr(C)] + struct Foo { + x: u8, + y: u16, + } + + type Bar = Foo; + + assert_eq!(offset_of!(Bar, x), 0); + assert_eq!(offset_of!(Bar, y), 2); +} + +#[test] +#[cfg(not(bootstrap))] +fn const_offset_of() { + #[repr(C)] + struct Foo { + x: u8, + y: u16, + } + + const X_OFFSET: usize = offset_of!(Foo, x); + const Y_OFFSET: usize = offset_of!(Foo, y); + + assert_eq!(X_OFFSET, 0); + assert_eq!(Y_OFFSET, 2); +} + +#[test] +#[cfg(not(bootstrap))] +fn offset_of_without_const_promotion() { + #[repr(C)] + struct Foo<SuppressConstPromotion> { + x: u8, + y: u16, + _scp: SuppressConstPromotion, + } + + // Normally, offset_of is always const promoted. + // The generic parameter prevents this from happening. + // This is needed to test the codegen impl of offset_of + fn inner<SuppressConstPromotion>() { + assert_eq!(offset_of!(Foo<SuppressConstPromotion>, x), 0); + assert_eq!(offset_of!(Foo<SuppressConstPromotion>, y), 2); + } + + inner::<()>(); +} + +#[test] +#[cfg(not(bootstrap))] +fn offset_of_addr() { + #[repr(C)] + struct Foo { + x: u8, + y: u16, + z: Bar, + } + + #[repr(C)] + struct Bar(u8, u8); + + let base = Foo { x: 0, y: 0, z: Bar(0, 0) }; + + assert_eq!(ptr::addr_of!(base).addr() + offset_of!(Foo, x), ptr::addr_of!(base.x).addr()); + assert_eq!(ptr::addr_of!(base).addr() + offset_of!(Foo, y), ptr::addr_of!(base.y).addr()); + assert_eq!(ptr::addr_of!(base).addr() + offset_of!(Foo, z.0), ptr::addr_of!(base.z.0).addr()); + assert_eq!(ptr::addr_of!(base).addr() + offset_of!(Foo, z.1), ptr::addr_of!(base.z.1).addr()); +} diff --git a/library/core/tests/nonzero.rs b/library/core/tests/nonzero.rs index a0ca919a8..007f84425 100644 --- a/library/core/tests/nonzero.rs +++ b/library/core/tests/nonzero.rs @@ -215,11 +215,13 @@ fn nonzero_const() { const ONE: Option<NonZeroU8> = NonZeroU8::new(1); assert!(ONE.is_some()); + /* FIXME(#110395) const FROM_NONZERO_U8: u8 = u8::from(NONZERO_U8); assert_eq!(FROM_NONZERO_U8, 5); const NONZERO_CONVERT: NonZeroU32 = NonZeroU32::from(NONZERO_U8); assert_eq!(NONZERO_CONVERT.get(), 5); + */ } #[test] @@ -334,3 +336,21 @@ fn test_nonzero_uint_rem() { let x: u32 = 42u32 % nz; assert_eq!(x, 2u32); } + +#[test] +fn test_signed_nonzero_neg() { + assert_eq!((-NonZeroI8::new(1).unwrap()).get(), -1); + assert_eq!((-NonZeroI8::new(-1).unwrap()).get(), 1); + + assert_eq!((-NonZeroI16::new(1).unwrap()).get(), -1); + assert_eq!((-NonZeroI16::new(-1).unwrap()).get(), 1); + + assert_eq!((-NonZeroI32::new(1).unwrap()).get(), -1); + assert_eq!((-NonZeroI32::new(-1).unwrap()).get(), 1); + + assert_eq!((-NonZeroI64::new(1).unwrap()).get(), -1); + assert_eq!((-NonZeroI64::new(-1).unwrap()).get(), 1); + + assert_eq!((-NonZeroI128::new(1).unwrap()).get(), -1); + assert_eq!((-NonZeroI128::new(-1).unwrap()).get(), 1); +} diff --git a/library/core/tests/num/const_from.rs b/library/core/tests/num/const_from.rs index aca18ef39..fa58e7718 100644 --- a/library/core/tests/num/const_from.rs +++ b/library/core/tests/num/const_from.rs @@ -1,3 +1,4 @@ +/* FIXME(#110395) #[test] fn from() { use core::convert::TryFrom; @@ -23,3 +24,4 @@ fn from() { const I16_FROM_U16: Result<i16, TryFromIntError> = i16::try_from(1u16); assert_eq!(I16_FROM_U16, Ok(1i16)); } +*/ diff --git a/library/core/tests/num/ieee754.rs b/library/core/tests/num/ieee754.rs index f6e5dfc98..48ab75b6f 100644 --- a/library/core/tests/num/ieee754.rs +++ b/library/core/tests/num/ieee754.rs @@ -39,7 +39,6 @@ macro_rules! assert_biteq { // ToString uses the default fmt::Display impl without special concerns, and bypasses other parts // of the formatting infrastructure, which makes it ideal for testing here. -#[allow(unused_macros)] macro_rules! roundtrip { ($f:expr => $t:ty) => { ($f).to_string().parse::<$t>().unwrap() diff --git a/library/core/tests/num/int_macros.rs b/library/core/tests/num/int_macros.rs index 18c55e43a..439bbe669 100644 --- a/library/core/tests/num/int_macros.rs +++ b/library/core/tests/num/int_macros.rs @@ -364,6 +364,32 @@ macro_rules! int_module { assert_eq!((0 as $T).borrowing_sub($T::MIN, false), ($T::MIN, true)); assert_eq!((0 as $T).borrowing_sub($T::MIN, true), ($T::MAX, false)); } + + #[test] + fn test_midpoint() { + assert_eq!(<$T>::midpoint(1, 3), 2); + assert_eq!(<$T>::midpoint(3, 1), 2); + + assert_eq!(<$T>::midpoint(0, 0), 0); + assert_eq!(<$T>::midpoint(0, 2), 1); + assert_eq!(<$T>::midpoint(2, 0), 1); + assert_eq!(<$T>::midpoint(2, 2), 2); + + assert_eq!(<$T>::midpoint(1, 4), 2); + assert_eq!(<$T>::midpoint(4, 1), 2); + assert_eq!(<$T>::midpoint(3, 4), 3); + assert_eq!(<$T>::midpoint(4, 3), 3); + + assert_eq!(<$T>::midpoint(<$T>::MIN, <$T>::MAX), -1); + assert_eq!(<$T>::midpoint(<$T>::MAX, <$T>::MIN), -1); + assert_eq!(<$T>::midpoint(<$T>::MIN, <$T>::MIN), <$T>::MIN); + assert_eq!(<$T>::midpoint(<$T>::MAX, <$T>::MAX), <$T>::MAX); + + assert_eq!(<$T>::midpoint(<$T>::MIN, 6), <$T>::MIN / 2 + 3); + assert_eq!(<$T>::midpoint(6, <$T>::MIN), <$T>::MIN / 2 + 3); + assert_eq!(<$T>::midpoint(<$T>::MAX, 6), <$T>::MAX / 2 + 3); + assert_eq!(<$T>::midpoint(6, <$T>::MAX), <$T>::MAX / 2 + 3); + } } }; } diff --git a/library/core/tests/num/mod.rs b/library/core/tests/num/mod.rs index c79e909e4..3f3659ba8 100644 --- a/library/core/tests/num/mod.rs +++ b/library/core/tests/num/mod.rs @@ -170,7 +170,7 @@ fn test_can_not_overflow() { for base in 2..=36 { let num = (<$t>::MAX as u128) + 1; - // Calcutate the string length for the smallest overflowing number: + // Calculate the string length for the smallest overflowing number: let max_len_string = format_radix(num, base as u128); // Ensure that string length is deemed to potentially overflow: assert!(can_overflow::<$t>(base, &max_len_string)); @@ -724,7 +724,7 @@ assume_usize_width! { } macro_rules! test_float { - ($modname: ident, $fty: ty, $inf: expr, $neginf: expr, $nan: expr) => { + ($modname: ident, $fty: ty, $inf: expr, $neginf: expr, $nan: expr, $min: expr, $max: expr, $min_pos: expr) => { mod $modname { #[test] fn min() { @@ -845,6 +845,38 @@ macro_rules! test_float { assert!(($nan as $fty).maximum($nan).is_nan()); } #[test] + fn midpoint() { + assert_eq!((0.5 as $fty).midpoint(0.5), 0.5); + assert_eq!((0.5 as $fty).midpoint(2.5), 1.5); + assert_eq!((3.0 as $fty).midpoint(4.0), 3.5); + assert_eq!((-3.0 as $fty).midpoint(4.0), 0.5); + assert_eq!((3.0 as $fty).midpoint(-4.0), -0.5); + assert_eq!((-3.0 as $fty).midpoint(-4.0), -3.5); + assert_eq!((0.0 as $fty).midpoint(0.0), 0.0); + assert_eq!((-0.0 as $fty).midpoint(-0.0), -0.0); + assert_eq!((-5.0 as $fty).midpoint(5.0), 0.0); + assert_eq!(($max as $fty).midpoint($min), 0.0); + assert_eq!(($min as $fty).midpoint($max), -0.0); + assert_eq!(($max as $fty).midpoint($min_pos), $max / 2.); + assert_eq!((-$max as $fty).midpoint($min_pos), -$max / 2.); + assert_eq!(($max as $fty).midpoint(-$min_pos), $max / 2.); + assert_eq!((-$max as $fty).midpoint(-$min_pos), -$max / 2.); + assert_eq!(($min_pos as $fty).midpoint($max), $max / 2.); + assert_eq!(($min_pos as $fty).midpoint(-$max), -$max / 2.); + assert_eq!((-$min_pos as $fty).midpoint($max), $max / 2.); + assert_eq!((-$min_pos as $fty).midpoint(-$max), -$max / 2.); + assert_eq!(($max as $fty).midpoint($max), $max); + assert_eq!(($min_pos as $fty).midpoint($min_pos), $min_pos); + assert_eq!((-$min_pos as $fty).midpoint(-$min_pos), -$min_pos); + assert_eq!(($max as $fty).midpoint(5.0), $max / 2.0 + 2.5); + assert_eq!(($max as $fty).midpoint(-5.0), $max / 2.0 - 2.5); + assert_eq!(($inf as $fty).midpoint($inf), $inf); + assert_eq!(($neginf as $fty).midpoint($neginf), $neginf); + assert!(($nan as $fty).midpoint(1.0).is_nan()); + assert!((1.0 as $fty).midpoint($nan).is_nan()); + assert!(($nan as $fty).midpoint($nan).is_nan()); + } + #[test] fn rem_euclid() { let a: $fty = 42.0; assert!($inf.rem_euclid(a).is_nan()); @@ -867,5 +899,23 @@ macro_rules! test_float { }; } -test_float!(f32, f32, f32::INFINITY, f32::NEG_INFINITY, f32::NAN); -test_float!(f64, f64, f64::INFINITY, f64::NEG_INFINITY, f64::NAN); +test_float!( + f32, + f32, + f32::INFINITY, + f32::NEG_INFINITY, + f32::NAN, + f32::MIN, + f32::MAX, + f32::MIN_POSITIVE +); +test_float!( + f64, + f64, + f64::INFINITY, + f64::NEG_INFINITY, + f64::NAN, + f64::MIN, + f64::MAX, + f64::MIN_POSITIVE +); diff --git a/library/core/tests/num/uint_macros.rs b/library/core/tests/num/uint_macros.rs index 15ae9f232..7d6203db0 100644 --- a/library/core/tests/num/uint_macros.rs +++ b/library/core/tests/num/uint_macros.rs @@ -252,6 +252,32 @@ macro_rules! uint_module { assert_eq!($T::MAX.borrowing_sub(0, true), ($T::MAX - 1, false)); assert_eq!($T::MAX.borrowing_sub($T::MAX, true), ($T::MAX, true)); } + + #[test] + fn test_midpoint() { + assert_eq!(<$T>::midpoint(1, 3), 2); + assert_eq!(<$T>::midpoint(3, 1), 2); + + assert_eq!(<$T>::midpoint(0, 0), 0); + assert_eq!(<$T>::midpoint(0, 2), 1); + assert_eq!(<$T>::midpoint(2, 0), 1); + assert_eq!(<$T>::midpoint(2, 2), 2); + + assert_eq!(<$T>::midpoint(1, 4), 2); + assert_eq!(<$T>::midpoint(4, 1), 2); + assert_eq!(<$T>::midpoint(3, 4), 3); + assert_eq!(<$T>::midpoint(4, 3), 3); + + assert_eq!(<$T>::midpoint(<$T>::MIN, <$T>::MAX), (<$T>::MAX - <$T>::MIN) / 2); + assert_eq!(<$T>::midpoint(<$T>::MAX, <$T>::MIN), (<$T>::MAX - <$T>::MIN) / 2); + assert_eq!(<$T>::midpoint(<$T>::MIN, <$T>::MIN), <$T>::MIN); + assert_eq!(<$T>::midpoint(<$T>::MAX, <$T>::MAX), <$T>::MAX); + + assert_eq!(<$T>::midpoint(<$T>::MIN, 6), <$T>::MIN / 2 + 3); + assert_eq!(<$T>::midpoint(6, <$T>::MIN), <$T>::MIN / 2 + 3); + assert_eq!(<$T>::midpoint(<$T>::MAX, 6), (<$T>::MAX - <$T>::MIN) / 2 + 3); + assert_eq!(<$T>::midpoint(6, <$T>::MAX), (<$T>::MAX - <$T>::MIN) / 2 + 3); + } } }; } diff --git a/library/core/tests/option.rs b/library/core/tests/option.rs index dca6321cf..5defeb50d 100644 --- a/library/core/tests/option.rs +++ b/library/core/tests/option.rs @@ -88,6 +88,7 @@ fn test_and() { assert_eq!(x.and(Some(2)), None); assert_eq!(x.and(None::<isize>), None); + /* FIXME(#110395) const FOO: Option<isize> = Some(1); const A: Option<isize> = FOO.and(Some(2)); const B: Option<isize> = FOO.and(None); @@ -99,6 +100,7 @@ fn test_and() { const D: Option<isize> = BAR.and(None); assert_eq!(C, None); assert_eq!(D, None); + */ } #[test] @@ -119,6 +121,7 @@ fn test_and_then() { assert_eq!(x.and_then(plus_one), None); assert_eq!(x.and_then(none), None); + /* FIXME(#110395) const FOO: Option<isize> = Some(1); const A: Option<isize> = FOO.and_then(plus_one); const B: Option<isize> = FOO.and_then(none); @@ -130,6 +133,7 @@ fn test_and_then() { const D: Option<isize> = BAR.and_then(none); assert_eq!(C, None); assert_eq!(D, None); + */ } #[test] @@ -142,6 +146,7 @@ fn test_or() { assert_eq!(x.or(Some(2)), Some(2)); assert_eq!(x.or(None), None); + /* FIXME(#110395) const FOO: Option<isize> = Some(1); const A: Option<isize> = FOO.or(Some(2)); const B: Option<isize> = FOO.or(None); @@ -153,6 +158,7 @@ fn test_or() { const D: Option<isize> = BAR.or(None); assert_eq!(C, Some(2)); assert_eq!(D, None); + */ } #[test] @@ -173,6 +179,7 @@ fn test_or_else() { assert_eq!(x.or_else(two), Some(2)); assert_eq!(x.or_else(none), None); +/* FIXME(#110395) const FOO: Option<isize> = Some(1); const A: Option<isize> = FOO.or_else(two); const B: Option<isize> = FOO.or_else(none); @@ -184,6 +191,7 @@ fn test_or_else() { const D: Option<isize> = BAR.or_else(none); assert_eq!(C, Some(2)); assert_eq!(D, None); +*/ } #[test] @@ -215,10 +223,12 @@ fn test_unwrap_or() { let x: Option<isize> = None; assert_eq!(x.unwrap_or(2), 2); + /* FIXME(#110395) const A: isize = Some(1).unwrap_or(2); const B: isize = None.unwrap_or(2); assert_eq!(A, 1); assert_eq!(B, 2); + */ } #[test] @@ -233,10 +243,12 @@ fn test_unwrap_or_else() { let x: Option<isize> = None; assert_eq!(x.unwrap_or_else(two), 2); + /* FIXME(#110395) const A: isize = Some(1).unwrap_or_else(two); const B: isize = None.unwrap_or_else(two); assert_eq!(A, 1); assert_eq!(B, 2); + */ } #[test] @@ -439,14 +451,15 @@ fn option_const() { const OPTION: Option<usize> = Some(32); assert_eq!(OPTION, Some(32)); - const OPTION_FROM: Option<usize> = Option::from(32); - assert_eq!(OPTION_FROM, Some(32)); + // FIXME(#110395) + // const OPTION_FROM: Option<usize> = Option::from(32); + // assert_eq!(OPTION_FROM, Some(32)); const REF: Option<&usize> = OPTION.as_ref(); assert_eq!(REF, Some(&32)); - const REF_FROM: Option<&usize> = Option::from(&OPTION); - assert_eq!(REF_FROM, Some(&32)); + // const REF_FROM: Option<&usize> = Option::from(&OPTION); + // assert_eq!(REF_FROM, Some(&32)); const IS_SOME: bool = OPTION.is_some(); assert!(IS_SOME); @@ -474,7 +487,7 @@ const fn option_const_mut() { None => unreachable!(), } } - +/* FIXME(const-hack) { let as_mut: Option<&mut usize> = Option::from(&mut option); match as_mut { @@ -482,6 +495,7 @@ const fn option_const_mut() { None => unreachable!(), } } +*/ } #[test] diff --git a/library/core/tests/time.rs b/library/core/tests/time.rs index 2975c81f8..872611937 100644 --- a/library/core/tests/time.rs +++ b/library/core/tests/time.rs @@ -425,14 +425,16 @@ fn duration_const() { const SECONDS_F32: f32 = Duration::SECOND.as_secs_f32(); assert_eq!(SECONDS_F32, 1.0); - const FROM_SECONDS_F32: Duration = Duration::from_secs_f32(1.0); - assert_eq!(FROM_SECONDS_F32, Duration::SECOND); + // FIXME(#110395) + // const FROM_SECONDS_F32: Duration = Duration::from_secs_f32(1.0); + // assert_eq!(FROM_SECONDS_F32, Duration::SECOND); const SECONDS_F64: f64 = Duration::SECOND.as_secs_f64(); assert_eq!(SECONDS_F64, 1.0); - const FROM_SECONDS_F64: Duration = Duration::from_secs_f64(1.0); - assert_eq!(FROM_SECONDS_F64, Duration::SECOND); + // FIXME(#110395) + // const FROM_SECONDS_F64: Duration = Duration::from_secs_f64(1.0); + // assert_eq!(FROM_SECONDS_F64, Duration::SECOND); const MILLIS: u128 = Duration::SECOND.as_millis(); assert_eq!(MILLIS, 1_000); @@ -463,6 +465,7 @@ fn duration_const() { const CHECKED_MUL: Option<Duration> = Duration::SECOND.checked_mul(1); assert_eq!(CHECKED_MUL, Some(Duration::SECOND)); +/* FIXME(#110395) const MUL_F32: Duration = Duration::SECOND.mul_f32(1.0); assert_eq!(MUL_F32, Duration::SECOND); @@ -477,6 +480,7 @@ fn duration_const() { const DIV_F64: Duration = Duration::SECOND.div_f64(1.0); assert_eq!(DIV_F64, Duration::SECOND); +*/ const DIV_DURATION_F32: f32 = Duration::SECOND.div_duration_f32(Duration::SECOND); assert_eq!(DIV_DURATION_F32, 1.0); |