diff options
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 /vendor/itoa-0.4.8/src | |
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 'vendor/itoa-0.4.8/src')
-rw-r--r-- | vendor/itoa-0.4.8/src/lib.rs | 358 | ||||
-rw-r--r-- | vendor/itoa-0.4.8/src/udiv128.rs | 45 |
2 files changed, 403 insertions, 0 deletions
diff --git a/vendor/itoa-0.4.8/src/lib.rs b/vendor/itoa-0.4.8/src/lib.rs new file mode 100644 index 000000000..8d4582e02 --- /dev/null +++ b/vendor/itoa-0.4.8/src/lib.rs @@ -0,0 +1,358 @@ +//! [![github]](https://github.com/dtolnay/itoa) [![crates-io]](https://crates.io/crates/itoa) [![docs-rs]](https://docs.rs/itoa) +//! +//! [github]: https://img.shields.io/badge/github-8da0cb?style=for-the-badge&labelColor=555555&logo=github +//! [crates-io]: https://img.shields.io/badge/crates.io-fc8d62?style=for-the-badge&labelColor=555555&logo=rust +//! [docs-rs]: https://img.shields.io/badge/docs.rs-66c2a5?style=for-the-badge&labelColor=555555&logoColor=white&logo=data:image/svg+xml;base64,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 +//! +//! <br> +//! +//! This crate provides fast functions for printing integer primitives to an +//! [`io::Write`] or a [`fmt::Write`]. The implementation comes straight from +//! [libcore] but avoids the performance penalty of going through +//! [`fmt::Formatter`]. +//! +//! See also [`dtoa`] for printing floating point primitives. +//! +//! [`io::Write`]: https://doc.rust-lang.org/std/io/trait.Write.html +//! [`fmt::Write`]: https://doc.rust-lang.org/core/fmt/trait.Write.html +//! [libcore]: https://github.com/rust-lang/rust/blob/b8214dc6c6fc20d0a660fb5700dca9ebf51ebe89/src/libcore/fmt/num.rs#L201-L254 +//! [`fmt::Formatter`]: https://doc.rust-lang.org/std/fmt/struct.Formatter.html +//! [`dtoa`]: https://github.com/dtolnay/dtoa +//! +//! <br> +//! +//! # Performance (lower is better) +//! +//! ![performance](https://raw.githubusercontent.com/dtolnay/itoa/master/performance.png) +//! +//! <br> +//! +//! # Examples +//! +//! ```edition2018 +//! use std::{fmt, io}; +//! +//! fn demo_itoa_write() -> io::Result<()> { +//! // Write to a vector or other io::Write. +//! let mut buf = Vec::new(); +//! itoa::write(&mut buf, 128u64)?; +//! println!("{:?}", buf); +//! +//! // Write to a stack buffer. +//! let mut bytes = [0u8; 20]; +//! let n = itoa::write(&mut bytes[..], 128u64)?; +//! println!("{:?}", &bytes[..n]); +//! +//! Ok(()) +//! } +//! +//! fn demo_itoa_fmt() -> fmt::Result { +//! // Write to a string. +//! let mut s = String::new(); +//! itoa::fmt(&mut s, 128u64)?; +//! println!("{}", s); +//! +//! Ok(()) +//! } +//! ``` + +#![doc(html_root_url = "https://docs.rs/itoa/0.4.8")] +#![cfg_attr(not(feature = "std"), no_std)] +#![cfg_attr(feature = "cargo-clippy", allow(renamed_and_removed_lints))] +#![cfg_attr( + feature = "cargo-clippy", + allow( + expl_impl_clone_on_copy, + missing_errors_doc, + must_use_candidate, + transmute_ptr_to_ptr + ) +)] + +#[cfg(feature = "i128")] +mod udiv128; + +#[cfg(feature = "std")] +use std::{fmt, io, mem, ptr, slice, str}; + +#[cfg(not(feature = "std"))] +use core::{fmt, mem, ptr, slice, str}; + +/// Write integer to an `io::Write`. +#[cfg(feature = "std")] +#[inline] +pub fn write<W: io::Write, V: Integer>(mut wr: W, value: V) -> io::Result<usize> { + let mut buf = Buffer::new(); + let s = buf.format(value); + match wr.write_all(s.as_bytes()) { + Ok(()) => Ok(s.len()), + Err(e) => Err(e), + } +} + +/// Write integer to an `fmt::Write`. +#[inline] +pub fn fmt<W: fmt::Write, V: Integer>(mut wr: W, value: V) -> fmt::Result { + let mut buf = Buffer::new(); + wr.write_str(buf.format(value)) +} + +/// A safe API for formatting integers to text. +/// +/// # Example +/// +/// ``` +/// let mut buffer = itoa::Buffer::new(); +/// let printed = buffer.format(1234); +/// assert_eq!(printed, "1234"); +/// ``` +#[derive(Copy)] +pub struct Buffer { + bytes: [u8; I128_MAX_LEN], +} + +impl Default for Buffer { + #[inline] + fn default() -> Buffer { + Buffer::new() + } +} + +impl Clone for Buffer { + #[inline] + fn clone(&self) -> Self { + Buffer::new() + } +} + +impl Buffer { + /// This is a cheap operation; you don't need to worry about reusing buffers + /// for efficiency. + #[inline] + #[allow(deprecated)] + pub fn new() -> Buffer { + Buffer { + bytes: unsafe { mem::uninitialized() }, + } + } + + /// Print an integer into this buffer and return a reference to its string representation + /// within the buffer. + pub fn format<I: Integer>(&mut self, i: I) -> &str { + i.write(self) + } +} + +// Seal to prevent downstream implementations of the Integer trait. +mod private { + pub trait Sealed {} +} + +/// An integer that can be formatted by `itoa::write` and `itoa::fmt`. +/// +/// This trait is sealed and cannot be implemented for types outside of itoa. +pub trait Integer: private::Sealed { + // Not public API. + #[doc(hidden)] + fn write(self, buf: &mut Buffer) -> &str; +} + +trait IntegerPrivate<B> { + fn write_to(self, buf: &mut B) -> &[u8]; +} + +const DEC_DIGITS_LUT: &'static [u8] = b"\ + 0001020304050607080910111213141516171819\ + 2021222324252627282930313233343536373839\ + 4041424344454647484950515253545556575859\ + 6061626364656667686970717273747576777879\ + 8081828384858687888990919293949596979899"; + +// Adaptation of the original implementation at +// https://github.com/rust-lang/rust/blob/b8214dc6c6fc20d0a660fb5700dca9ebf51ebe89/src/libcore/fmt/num.rs#L188-L266 +macro_rules! impl_IntegerCommon { + ($max_len:expr, $t:ident) => { + impl Integer for $t { + #[inline] + fn write(self, buf: &mut Buffer) -> &str { + unsafe { + debug_assert!($max_len <= I128_MAX_LEN); + let buf = mem::transmute::<&mut [u8; I128_MAX_LEN], &mut [u8; $max_len]>( + &mut buf.bytes, + ); + let bytes = self.write_to(buf); + str::from_utf8_unchecked(bytes) + } + } + } + + impl private::Sealed for $t {} + }; +} + +macro_rules! impl_Integer { + ($($max_len:expr => $t:ident),* as $conv_fn:ident) => {$( + impl_IntegerCommon!($max_len, $t); + + impl IntegerPrivate<[u8; $max_len]> for $t { + #[allow(unused_comparisons)] + #[inline] + fn write_to(self, buf: &mut [u8; $max_len]) -> &[u8] { + let is_nonnegative = self >= 0; + let mut n = if is_nonnegative { + self as $conv_fn + } else { + // convert the negative num to positive by summing 1 to it's 2 complement + (!(self as $conv_fn)).wrapping_add(1) + }; + let mut curr = buf.len() as isize; + let buf_ptr = buf.as_mut_ptr(); + let lut_ptr = DEC_DIGITS_LUT.as_ptr(); + + unsafe { + // need at least 16 bits for the 4-characters-at-a-time to work. + if mem::size_of::<$t>() >= 2 { + // eagerly decode 4 characters at a time + while n >= 10000 { + let rem = (n % 10000) as isize; + n /= 10000; + + let d1 = (rem / 100) << 1; + let d2 = (rem % 100) << 1; + curr -= 4; + ptr::copy_nonoverlapping(lut_ptr.offset(d1), buf_ptr.offset(curr), 2); + ptr::copy_nonoverlapping(lut_ptr.offset(d2), buf_ptr.offset(curr + 2), 2); + } + } + + // if we reach here numbers are <= 9999, so at most 4 chars long + let mut n = n as isize; // possibly reduce 64bit math + + // decode 2 more chars, if > 2 chars + if n >= 100 { + let d1 = (n % 100) << 1; + n /= 100; + curr -= 2; + ptr::copy_nonoverlapping(lut_ptr.offset(d1), buf_ptr.offset(curr), 2); + } + + // decode last 1 or 2 chars + if n < 10 { + curr -= 1; + *buf_ptr.offset(curr) = (n as u8) + b'0'; + } else { + let d1 = n << 1; + curr -= 2; + ptr::copy_nonoverlapping(lut_ptr.offset(d1), buf_ptr.offset(curr), 2); + } + + if !is_nonnegative { + curr -= 1; + *buf_ptr.offset(curr) = b'-'; + } + } + + let len = buf.len() - curr as usize; + unsafe { slice::from_raw_parts(buf_ptr.offset(curr), len) } + } + } + )*}; +} + +const I8_MAX_LEN: usize = 4; +const U8_MAX_LEN: usize = 3; +const I16_MAX_LEN: usize = 6; +const U16_MAX_LEN: usize = 5; +const I32_MAX_LEN: usize = 11; +const U32_MAX_LEN: usize = 10; +const I64_MAX_LEN: usize = 20; +const U64_MAX_LEN: usize = 20; + +impl_Integer!( + I8_MAX_LEN => i8, + U8_MAX_LEN => u8, + I16_MAX_LEN => i16, + U16_MAX_LEN => u16, + I32_MAX_LEN => i32, + U32_MAX_LEN => u32 + as u32); + +impl_Integer!(I64_MAX_LEN => i64, U64_MAX_LEN => u64 as u64); + +#[cfg(target_pointer_width = "16")] +impl_Integer!(I16_MAX_LEN => isize, U16_MAX_LEN => usize as u16); + +#[cfg(target_pointer_width = "32")] +impl_Integer!(I32_MAX_LEN => isize, U32_MAX_LEN => usize as u32); + +#[cfg(target_pointer_width = "64")] +impl_Integer!(I64_MAX_LEN => isize, U64_MAX_LEN => usize as u64); + +#[cfg(all(feature = "i128"))] +macro_rules! impl_Integer128 { + ($($max_len:expr => $t:ident),*) => {$( + impl_IntegerCommon!($max_len, $t); + + impl IntegerPrivate<[u8; $max_len]> for $t { + #[allow(unused_comparisons)] + #[inline] + fn write_to(self, buf: &mut [u8; $max_len]) -> &[u8] { + let is_nonnegative = self >= 0; + let n = if is_nonnegative { + self as u128 + } else { + // convert the negative num to positive by summing 1 to it's 2 complement + (!(self as u128)).wrapping_add(1) + }; + let mut curr = buf.len() as isize; + let buf_ptr = buf.as_mut_ptr(); + + unsafe { + // Divide by 10^19 which is the highest power less than 2^64. + let (n, rem) = udiv128::udivmod_1e19(n); + let buf1 = buf_ptr.offset(curr - U64_MAX_LEN as isize) as *mut [u8; U64_MAX_LEN]; + curr -= rem.write_to(&mut *buf1).len() as isize; + + if n != 0 { + // Memset the base10 leading zeros of rem. + let target = buf.len() as isize - 19; + ptr::write_bytes(buf_ptr.offset(target), b'0', (curr - target) as usize); + curr = target; + + // Divide by 10^19 again. + let (n, rem) = udiv128::udivmod_1e19(n); + let buf2 = buf_ptr.offset(curr - U64_MAX_LEN as isize) as *mut [u8; U64_MAX_LEN]; + curr -= rem.write_to(&mut *buf2).len() as isize; + + if n != 0 { + // Memset the leading zeros. + let target = buf.len() as isize - 38; + ptr::write_bytes(buf_ptr.offset(target), b'0', (curr - target) as usize); + curr = target; + + // There is at most one digit left + // because u128::max / 10^19 / 10^19 is 3. + curr -= 1; + *buf_ptr.offset(curr) = (n as u8) + b'0'; + } + } + + if !is_nonnegative { + curr -= 1; + *buf_ptr.offset(curr) = b'-'; + } + + let len = buf.len() - curr as usize; + slice::from_raw_parts(buf_ptr.offset(curr), len) + } + } + } + )*}; +} + +#[cfg(all(feature = "i128"))] +const U128_MAX_LEN: usize = 39; +const I128_MAX_LEN: usize = 40; + +#[cfg(all(feature = "i128"))] +impl_Integer128!(I128_MAX_LEN => i128, U128_MAX_LEN => u128); diff --git a/vendor/itoa-0.4.8/src/udiv128.rs b/vendor/itoa-0.4.8/src/udiv128.rs new file mode 100644 index 000000000..617c1c17c --- /dev/null +++ b/vendor/itoa-0.4.8/src/udiv128.rs @@ -0,0 +1,45 @@ +/// Multiply unsigned 128 bit integers, return upper 128 bits of the result +#[inline] +fn u128_mulhi(x: u128, y: u128) -> u128 { + let x_lo = x as u64; + let x_hi = (x >> 64) as u64; + let y_lo = y as u64; + let y_hi = (y >> 64) as u64; + + // handle possibility of overflow + let carry = (x_lo as u128 * y_lo as u128) >> 64; + let m = x_lo as u128 * y_hi as u128 + carry; + let high1 = m >> 64; + + let m_lo = m as u64; + let high2 = x_hi as u128 * y_lo as u128 + m_lo as u128 >> 64; + + x_hi as u128 * y_hi as u128 + high1 + high2 +} + +/// Divide `n` by 1e19 and return quotient and remainder +/// +/// Integer division algorithm is based on the following paper: +/// +/// T. Granlund and P. Montgomery, “Division by Invariant Integers Using Multiplication” +/// in Proc. of the SIGPLAN94 Conference on Programming Language Design and +/// Implementation, 1994, pp. 61–72 +/// +#[inline] +pub fn udivmod_1e19(n: u128) -> (u128, u64) { + let d = 10_000_000_000_000_000_000_u64; // 10^19 + + let quot = if n < 1 << 83 { + ((n >> 19) as u64 / (d >> 19)) as u128 + } else { + let factor = + (8507059173023461586_u64 as u128) << 64 | 10779635027931437427 as u128; + u128_mulhi(n, factor) >> 62 + }; + + let rem = (n - quot * d as u128) as u64; + debug_assert_eq!(quot, n / d as u128); + debug_assert_eq!(rem as u128, n % d as u128); + + (quot, rem) +} |