diff options
Diffstat (limited to 'library/core/src/num')
| -rw-r--r-- | library/core/src/num/bignum.rs | 2 | ||||
| -rw-r--r-- | library/core/src/num/dec2flt/decimal.rs | 2 | ||||
| -rw-r--r-- | library/core/src/num/error.rs | 20 | ||||
| -rw-r--r-- | library/core/src/num/f32.rs | 153 | ||||
| -rw-r--r-- | library/core/src/num/f64.rs | 153 | ||||
| -rw-r--r-- | library/core/src/num/int_macros.rs | 116 | ||||
| -rw-r--r-- | library/core/src/num/mod.rs | 14 | ||||
| -rw-r--r-- | library/core/src/num/nonzero.rs | 46 | ||||
| -rw-r--r-- | library/core/src/num/uint_macros.rs | 42 |
9 files changed, 436 insertions, 112 deletions
diff --git a/library/core/src/num/bignum.rs b/library/core/src/num/bignum.rs index de85fdd6e..d2a21b6b3 100644 --- a/library/core/src/num/bignum.rs +++ b/library/core/src/num/bignum.rs @@ -137,7 +137,7 @@ macro_rules! define_bignum { // Find the most significant non-zero digit. let msd = digits.iter().rposition(|&x| x != 0); match msd { - Some(msd) => msd * digitbits + digits[msd].log2() as usize + 1, + Some(msd) => msd * digitbits + digits[msd].ilog2() as usize + 1, // There are no non-zero digits, i.e., the number is zero. _ => 0, } diff --git a/library/core/src/num/dec2flt/decimal.rs b/library/core/src/num/dec2flt/decimal.rs index f8edc3625..2019f71e6 100644 --- a/library/core/src/num/dec2flt/decimal.rs +++ b/library/core/src/num/dec2flt/decimal.rs @@ -32,7 +32,7 @@ impl Default for Decimal { impl Decimal { /// The maximum number of digits required to unambiguously round a float. /// - /// For a double-precision IEEE-754 float, this required 767 digits, + /// For a double-precision IEEE 754 float, this required 767 digits, /// so we store the max digits + 1. /// /// We can exactly represent a float in radix `b` from radix 2 if diff --git a/library/core/src/num/error.rs b/library/core/src/num/error.rs index 1a223016d..1f6b40e5d 100644 --- a/library/core/src/num/error.rs +++ b/library/core/src/num/error.rs @@ -1,6 +1,8 @@ //! Error types for conversion to integral types. use crate::convert::Infallible; +#[cfg(not(bootstrap))] +use crate::error::Error; use crate::fmt; /// The error type returned when a checked integral type conversion fails. @@ -144,3 +146,21 @@ impl fmt::Display for ParseIntError { self.__description().fmt(f) } } + +#[cfg(not(bootstrap))] +#[stable(feature = "rust1", since = "1.0.0")] +impl Error for ParseIntError { + #[allow(deprecated)] + fn description(&self) -> &str { + self.__description() + } +} + +#[cfg(not(bootstrap))] +#[stable(feature = "try_from", since = "1.34.0")] +impl Error for TryFromIntError { + #[allow(deprecated)] + fn description(&self) -> &str { + self.__description() + } +} diff --git a/library/core/src/num/f32.rs b/library/core/src/num/f32.rs index 6548ad2e5..2c6a0ba64 100644 --- a/library/core/src/num/f32.rs +++ b/library/core/src/num/f32.rs @@ -1,4 +1,4 @@ -//! Constants specific to the `f32` single-precision floating point type. +//! Constants for the `f32` single-precision floating point type. //! //! *[See also the `f32` primitive type][f32].* //! @@ -394,7 +394,7 @@ impl f32 { /// Not a Number (NaN). /// - /// Note that IEEE-745 doesn't define just a single NaN value; + /// Note that IEEE 754 doesn't define just a single NaN value; /// a plethora of bit patterns are considered to be NaN. /// Furthermore, the standard makes a difference /// between a "signaling" and a "quiet" NaN, @@ -632,7 +632,7 @@ impl f32 { } /// Returns `true` if `self` has a positive sign, including `+0.0`, NaNs with - /// positive sign bit and positive infinity. Note that IEEE-745 doesn't assign any + /// positive sign bit and positive infinity. Note that IEEE 754 doesn't assign any /// meaning to the sign bit in case of a NaN, and as Rust doesn't guarantee that /// the bit pattern of NaNs are conserved over arithmetic operations, the result of /// `is_sign_positive` on a NaN might produce an unexpected result in some cases. @@ -654,7 +654,7 @@ impl f32 { } /// Returns `true` if `self` has a negative sign, including `-0.0`, NaNs with - /// negative sign bit and negative infinity. Note that IEEE-745 doesn't assign any + /// negative sign bit and negative infinity. Note that IEEE 754 doesn't assign any /// meaning to the sign bit in case of a NaN, and as Rust doesn't guarantee that /// the bit pattern of NaNs are conserved over arithmetic operations, the result of /// `is_sign_negative` on a NaN might produce an unexpected result in some cases. @@ -678,6 +678,106 @@ impl f32 { unsafe { mem::transmute::<f32, u32>(self) & 0x8000_0000 != 0 } } + /// Returns the least number greater than `self`. + /// + /// Let `TINY` be the smallest representable positive `f32`. Then, + /// - if `self.is_nan()`, this returns `self`; + /// - if `self` is [`NEG_INFINITY`], this returns [`MIN`]; + /// - if `self` is `-TINY`, this returns -0.0; + /// - if `self` is -0.0 or +0.0, this returns `TINY`; + /// - if `self` is [`MAX`] or [`INFINITY`], this returns [`INFINITY`]; + /// - otherwise the unique least value greater than `self` is returned. + /// + /// The identity `x.next_up() == -(-x).next_down()` holds for all non-NaN `x`. When `x` + /// is finite `x == x.next_up().next_down()` also holds. + /// + /// ```rust + /// #![feature(float_next_up_down)] + /// // f32::EPSILON is the difference between 1.0 and the next number up. + /// assert_eq!(1.0f32.next_up(), 1.0 + f32::EPSILON); + /// // But not for most numbers. + /// assert!(0.1f32.next_up() < 0.1 + f32::EPSILON); + /// assert_eq!(16777216f32.next_up(), 16777218.0); + /// ``` + /// + /// [`NEG_INFINITY`]: Self::NEG_INFINITY + /// [`INFINITY`]: Self::INFINITY + /// [`MIN`]: Self::MIN + /// [`MAX`]: Self::MAX + #[unstable(feature = "float_next_up_down", issue = "91399")] + #[rustc_const_unstable(feature = "float_next_up_down", issue = "91399")] + pub const fn next_up(self) -> Self { + // We must use strictly integer arithmetic to prevent denormals from + // flushing to zero after an arithmetic operation on some platforms. + const TINY_BITS: u32 = 0x1; // Smallest positive f32. + const CLEAR_SIGN_MASK: u32 = 0x7fff_ffff; + + let bits = self.to_bits(); + if self.is_nan() || bits == Self::INFINITY.to_bits() { + return self; + } + + let abs = bits & CLEAR_SIGN_MASK; + let next_bits = if abs == 0 { + TINY_BITS + } else if bits == abs { + bits + 1 + } else { + bits - 1 + }; + Self::from_bits(next_bits) + } + + /// Returns the greatest number less than `self`. + /// + /// Let `TINY` be the smallest representable positive `f32`. Then, + /// - if `self.is_nan()`, this returns `self`; + /// - if `self` is [`INFINITY`], this returns [`MAX`]; + /// - if `self` is `TINY`, this returns 0.0; + /// - if `self` is -0.0 or +0.0, this returns `-TINY`; + /// - if `self` is [`MIN`] or [`NEG_INFINITY`], this returns [`NEG_INFINITY`]; + /// - otherwise the unique greatest value less than `self` is returned. + /// + /// The identity `x.next_down() == -(-x).next_up()` holds for all non-NaN `x`. When `x` + /// is finite `x == x.next_down().next_up()` also holds. + /// + /// ```rust + /// #![feature(float_next_up_down)] + /// let x = 1.0f32; + /// // Clamp value into range [0, 1). + /// let clamped = x.clamp(0.0, 1.0f32.next_down()); + /// assert!(clamped < 1.0); + /// assert_eq!(clamped.next_up(), 1.0); + /// ``` + /// + /// [`NEG_INFINITY`]: Self::NEG_INFINITY + /// [`INFINITY`]: Self::INFINITY + /// [`MIN`]: Self::MIN + /// [`MAX`]: Self::MAX + #[unstable(feature = "float_next_up_down", issue = "91399")] + #[rustc_const_unstable(feature = "float_next_up_down", issue = "91399")] + pub const fn next_down(self) -> Self { + // We must use strictly integer arithmetic to prevent denormals from + // flushing to zero after an arithmetic operation on some platforms. + const NEG_TINY_BITS: u32 = 0x8000_0001; // Smallest (in magnitude) negative f32. + const CLEAR_SIGN_MASK: u32 = 0x7fff_ffff; + + let bits = self.to_bits(); + if self.is_nan() || bits == Self::NEG_INFINITY.to_bits() { + return self; + } + + let abs = bits & CLEAR_SIGN_MASK; + let next_bits = if abs == 0 { + NEG_TINY_BITS + } else if bits == abs { + bits - 1 + } else { + bits + 1 + }; + Self::from_bits(next_bits) + } + /// Takes the reciprocal (inverse) of a number, `1/x`. /// /// ``` @@ -733,7 +833,7 @@ impl f32 { /// Returns the maximum of the two numbers, ignoring NaN. /// /// If one of the arguments is NaN, then the other argument is returned. - /// This follows the IEEE-754 2008 semantics for maxNum, except for handling of signaling NaNs; + /// This follows the IEEE 754-2008 semantics for maxNum, except for handling of signaling NaNs; /// this function handles all NaNs the same way and avoids maxNum's problems with associativity. /// This also matches the behavior of libm’s fmax. /// @@ -753,7 +853,7 @@ impl f32 { /// Returns the minimum of the two numbers, ignoring NaN. /// /// If one of the arguments is NaN, then the other argument is returned. - /// This follows the IEEE-754 2008 semantics for minNum, except for handling of signaling NaNs; + /// This follows the IEEE 754-2008 semantics for minNum, except for handling of signaling NaNs; /// this function handles all NaNs the same way and avoids minNum's problems with associativity. /// This also matches the behavior of libm’s fmin. /// @@ -933,10 +1033,14 @@ impl f32 { } } } - // SAFETY: `u32` is a plain old datatype so we can always... uh... - // ...look, just pretend you forgot what you just read. - // Stability concerns. - let rt_f32_to_u32 = |rt| unsafe { mem::transmute::<f32, u32>(rt) }; + + #[inline(always)] // See https://github.com/rust-lang/compiler-builtins/issues/491 + fn rt_f32_to_u32(x: f32) -> u32 { + // SAFETY: `u32` is a plain old datatype so we can always... uh... + // ...look, just pretend you forgot what you just read. + // Stability concerns. + unsafe { mem::transmute(x) } + } // SAFETY: We use internal implementations that either always work or fail at compile time. unsafe { intrinsics::const_eval_select((self,), ct_f32_to_u32, rt_f32_to_u32) } } @@ -947,9 +1051,9 @@ impl f32 { /// It turns out this is incredibly portable, for two reasons: /// /// * Floats and Ints have the same endianness on all supported platforms. - /// * IEEE-754 very precisely specifies the bit layout of floats. + /// * IEEE 754 very precisely specifies the bit layout of floats. /// - /// However there is one caveat: prior to the 2008 version of IEEE-754, how + /// However there is one caveat: prior to the 2008 version of IEEE 754, how /// to interpret the NaN signaling bit wasn't actually specified. Most platforms /// (notably x86 and ARM) picked the interpretation that was ultimately /// standardized in 2008, but some didn't (notably MIPS). As a result, all @@ -1021,10 +1125,14 @@ impl f32 { } } } - // SAFETY: `u32` is a plain old datatype so we can always... uh... - // ...look, just pretend you forgot what you just read. - // Stability concerns. - let rt_u32_to_f32 = |rt| unsafe { mem::transmute::<u32, f32>(rt) }; + + #[inline(always)] // See https://github.com/rust-lang/compiler-builtins/issues/491 + fn rt_u32_to_f32(x: u32) -> f32 { + // SAFETY: `u32` is a plain old datatype so we can always... uh... + // ...look, just pretend you forgot what you just read. + // Stability concerns. + unsafe { mem::transmute(x) } + } // SAFETY: We use internal implementations that either always work or fail at compile time. unsafe { intrinsics::const_eval_select((v,), ct_u32_to_f32, rt_u32_to_f32) } } @@ -1282,15 +1390,14 @@ impl f32 { #[must_use = "method returns a new number and does not mutate the original value"] #[stable(feature = "clamp", since = "1.50.0")] #[inline] - pub fn clamp(self, min: f32, max: f32) -> f32 { + pub fn clamp(mut self, min: f32, max: f32) -> f32 { assert!(min <= max); - let mut x = self; - if x < min { - x = min; + if self < min { + self = min; } - if x > max { - x = max; + if self > max { + self = max; } - x + self } } diff --git a/library/core/src/num/f64.rs b/library/core/src/num/f64.rs index 75c92c2f8..fd3c18ce2 100644 --- a/library/core/src/num/f64.rs +++ b/library/core/src/num/f64.rs @@ -1,4 +1,4 @@ -//! Constants specific to the `f64` double-precision floating point type. +//! Constants for the `f64` double-precision floating point type. //! //! *[See also the `f64` primitive type][f64].* //! @@ -393,7 +393,7 @@ impl f64 { /// Not a Number (NaN). /// - /// Note that IEEE-745 doesn't define just a single NaN value; + /// Note that IEEE 754 doesn't define just a single NaN value; /// a plethora of bit patterns are considered to be NaN. /// Furthermore, the standard makes a difference /// between a "signaling" and a "quiet" NaN, @@ -624,7 +624,7 @@ impl f64 { } /// Returns `true` if `self` has a positive sign, including `+0.0`, NaNs with - /// positive sign bit and positive infinity. Note that IEEE-745 doesn't assign any + /// positive sign bit and positive infinity. Note that IEEE 754 doesn't assign any /// meaning to the sign bit in case of a NaN, and as Rust doesn't guarantee that /// the bit pattern of NaNs are conserved over arithmetic operations, the result of /// `is_sign_positive` on a NaN might produce an unexpected result in some cases. @@ -655,7 +655,7 @@ impl f64 { } /// Returns `true` if `self` has a negative sign, including `-0.0`, NaNs with - /// negative sign bit and negative infinity. Note that IEEE-745 doesn't assign any + /// negative sign bit and negative infinity. Note that IEEE 754 doesn't assign any /// meaning to the sign bit in case of a NaN, and as Rust doesn't guarantee that /// the bit pattern of NaNs are conserved over arithmetic operations, the result of /// `is_sign_negative` on a NaN might produce an unexpected result in some cases. @@ -688,6 +688,106 @@ impl f64 { self.is_sign_negative() } + /// Returns the least number greater than `self`. + /// + /// Let `TINY` be the smallest representable positive `f64`. Then, + /// - if `self.is_nan()`, this returns `self`; + /// - if `self` is [`NEG_INFINITY`], this returns [`MIN`]; + /// - if `self` is `-TINY`, this returns -0.0; + /// - if `self` is -0.0 or +0.0, this returns `TINY`; + /// - if `self` is [`MAX`] or [`INFINITY`], this returns [`INFINITY`]; + /// - otherwise the unique least value greater than `self` is returned. + /// + /// The identity `x.next_up() == -(-x).next_down()` holds for all non-NaN `x`. When `x` + /// is finite `x == x.next_up().next_down()` also holds. + /// + /// ```rust + /// #![feature(float_next_up_down)] + /// // f64::EPSILON is the difference between 1.0 and the next number up. + /// assert_eq!(1.0f64.next_up(), 1.0 + f64::EPSILON); + /// // But not for most numbers. + /// assert!(0.1f64.next_up() < 0.1 + f64::EPSILON); + /// assert_eq!(9007199254740992f64.next_up(), 9007199254740994.0); + /// ``` + /// + /// [`NEG_INFINITY`]: Self::NEG_INFINITY + /// [`INFINITY`]: Self::INFINITY + /// [`MIN`]: Self::MIN + /// [`MAX`]: Self::MAX + #[unstable(feature = "float_next_up_down", issue = "91399")] + #[rustc_const_unstable(feature = "float_next_up_down", issue = "91399")] + pub const fn next_up(self) -> Self { + // We must use strictly integer arithmetic to prevent denormals from + // flushing to zero after an arithmetic operation on some platforms. + const TINY_BITS: u64 = 0x1; // Smallest positive f64. + const CLEAR_SIGN_MASK: u64 = 0x7fff_ffff_ffff_ffff; + + let bits = self.to_bits(); + if self.is_nan() || bits == Self::INFINITY.to_bits() { + return self; + } + + let abs = bits & CLEAR_SIGN_MASK; + let next_bits = if abs == 0 { + TINY_BITS + } else if bits == abs { + bits + 1 + } else { + bits - 1 + }; + Self::from_bits(next_bits) + } + + /// Returns the greatest number less than `self`. + /// + /// Let `TINY` be the smallest representable positive `f64`. Then, + /// - if `self.is_nan()`, this returns `self`; + /// - if `self` is [`INFINITY`], this returns [`MAX`]; + /// - if `self` is `TINY`, this returns 0.0; + /// - if `self` is -0.0 or +0.0, this returns `-TINY`; + /// - if `self` is [`MIN`] or [`NEG_INFINITY`], this returns [`NEG_INFINITY`]; + /// - otherwise the unique greatest value less than `self` is returned. + /// + /// The identity `x.next_down() == -(-x).next_up()` holds for all non-NaN `x`. When `x` + /// is finite `x == x.next_down().next_up()` also holds. + /// + /// ```rust + /// #![feature(float_next_up_down)] + /// let x = 1.0f64; + /// // Clamp value into range [0, 1). + /// let clamped = x.clamp(0.0, 1.0f64.next_down()); + /// assert!(clamped < 1.0); + /// assert_eq!(clamped.next_up(), 1.0); + /// ``` + /// + /// [`NEG_INFINITY`]: Self::NEG_INFINITY + /// [`INFINITY`]: Self::INFINITY + /// [`MIN`]: Self::MIN + /// [`MAX`]: Self::MAX + #[unstable(feature = "float_next_up_down", issue = "91399")] + #[rustc_const_unstable(feature = "float_next_up_down", issue = "91399")] + pub const fn next_down(self) -> Self { + // We must use strictly integer arithmetic to prevent denormals from + // flushing to zero after an arithmetic operation on some platforms. + const NEG_TINY_BITS: u64 = 0x8000_0000_0000_0001; // Smallest (in magnitude) negative f64. + const CLEAR_SIGN_MASK: u64 = 0x7fff_ffff_ffff_ffff; + + let bits = self.to_bits(); + if self.is_nan() || bits == Self::NEG_INFINITY.to_bits() { + return self; + } + + let abs = bits & CLEAR_SIGN_MASK; + let next_bits = if abs == 0 { + NEG_TINY_BITS + } else if bits == abs { + bits - 1 + } else { + bits + 1 + }; + Self::from_bits(next_bits) + } + /// Takes the reciprocal (inverse) of a number, `1/x`. /// /// ``` @@ -744,7 +844,7 @@ impl f64 { /// Returns the maximum of the two numbers, ignoring NaN. /// /// If one of the arguments is NaN, then the other argument is returned. - /// This follows the IEEE-754 2008 semantics for maxNum, except for handling of signaling NaNs; + /// This follows the IEEE 754-2008 semantics for maxNum, except for handling of signaling NaNs; /// this function handles all NaNs the same way and avoids maxNum's problems with associativity. /// This also matches the behavior of libm’s fmax. /// @@ -764,7 +864,7 @@ impl f64 { /// Returns the minimum of the two numbers, ignoring NaN. /// /// If one of the arguments is NaN, then the other argument is returned. - /// This follows the IEEE-754 2008 semantics for minNum, except for handling of signaling NaNs; + /// This follows the IEEE 754-2008 semantics for minNum, except for handling of signaling NaNs; /// this function handles all NaNs the same way and avoids minNum's problems with associativity. /// This also matches the behavior of libm’s fmin. /// @@ -926,10 +1026,14 @@ impl f64 { } } } - // SAFETY: `u64` is a plain old datatype so we can always... uh... - // ...look, just pretend you forgot what you just read. - // Stability concerns. - let rt_f64_to_u64 = |rt| unsafe { mem::transmute::<f64, u64>(rt) }; + + #[inline(always)] // See https://github.com/rust-lang/compiler-builtins/issues/491 + fn rt_f64_to_u64(rt: f64) -> u64 { + // SAFETY: `u64` is a plain old datatype so we can always... uh... + // ...look, just pretend you forgot what you just read. + // Stability concerns. + unsafe { mem::transmute::<f64, u64>(rt) } + } // SAFETY: We use internal implementations that either always work or fail at compile time. unsafe { intrinsics::const_eval_select((self,), ct_f64_to_u64, rt_f64_to_u64) } } @@ -940,9 +1044,9 @@ impl f64 { /// It turns out this is incredibly portable, for two reasons: /// /// * Floats and Ints have the same endianness on all supported platforms. - /// * IEEE-754 very precisely specifies the bit layout of floats. + /// * IEEE 754 very precisely specifies the bit layout of floats. /// - /// However there is one caveat: prior to the 2008 version of IEEE-754, how + /// However there is one caveat: prior to the 2008 version of IEEE 754, how /// to interpret the NaN signaling bit wasn't actually specified. Most platforms /// (notably x86 and ARM) picked the interpretation that was ultimately /// standardized in 2008, but some didn't (notably MIPS). As a result, all @@ -1019,10 +1123,14 @@ impl f64 { } } } - // SAFETY: `u64` is a plain old datatype so we can always... uh... - // ...look, just pretend you forgot what you just read. - // Stability concerns. - let rt_u64_to_f64 = |rt| unsafe { mem::transmute::<u64, f64>(rt) }; + + #[inline(always)] // See https://github.com/rust-lang/compiler-builtins/issues/491 + fn rt_u64_to_f64(rt: u64) -> f64 { + // SAFETY: `u64` is a plain old datatype so we can always... uh... + // ...look, just pretend you forgot what you just read. + // Stability concerns. + unsafe { mem::transmute::<u64, f64>(rt) } + } // SAFETY: We use internal implementations that either always work or fail at compile time. unsafe { intrinsics::const_eval_select((v,), ct_u64_to_f64, rt_u64_to_f64) } } @@ -1280,15 +1388,14 @@ impl f64 { #[must_use = "method returns a new number and does not mutate the original value"] #[stable(feature = "clamp", since = "1.50.0")] #[inline] - pub fn clamp(self, min: f64, max: f64) -> f64 { + pub fn clamp(mut self, min: f64, max: f64) -> f64 { assert!(min <= max); - let mut x = self; - if x < min { - x = min; + if self < min { + self = min; } - if x > max { - x = max; + if self > max { + self = max; } - x + self } } diff --git a/library/core/src/num/int_macros.rs b/library/core/src/num/int_macros.rs index a66de19ba..e7deb728d 100644 --- a/library/core/src/num/int_macros.rs +++ b/library/core/src/num/int_macros.rs @@ -1518,6 +1518,51 @@ macro_rules! int_impl { (a as Self, b) } + /// Calculates `self + rhs + carry` without the ability to overflow. + /// + /// Performs "signed ternary addition" which takes in an extra bit to add, and may return an + /// additional bit of overflow. This signed function is used only on the highest-ordered data, + /// for which the signed overflow result indicates whether the big integer overflowed or not. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ``` + /// #![feature(bigint_helper_methods)] + #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".carrying_add(2, false), (7, false));")] + #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".carrying_add(2, true), (8, false));")] + #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.carrying_add(1, false), (", stringify!($SelfT), "::MIN, true));")] + #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.carrying_add(0, true), (", stringify!($SelfT), "::MIN, true));")] + #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.carrying_add(1, true), (", stringify!($SelfT), "::MIN + 1, true));")] + #[doc = concat!("assert_eq!(", + stringify!($SelfT), "::MAX.carrying_add(", stringify!($SelfT), "::MAX, true), ", + "(-1, true));" + )] + #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.carrying_add(-1, true), (", stringify!($SelfT), "::MIN, false));")] + #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".carrying_add(", stringify!($SelfT), "::MAX, true), (", stringify!($SelfT), "::MIN, true));")] + /// ``` + /// + /// If `carry` is false, this method is equivalent to [`overflowing_add`](Self::overflowing_add): + /// + /// ``` + /// #![feature(bigint_helper_methods)] + #[doc = concat!("assert_eq!(5_", stringify!($SelfT), ".carrying_add(2, false), 5_", stringify!($SelfT), ".overflowing_add(2));")] + #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.carrying_add(1, false), ", stringify!($SelfT), "::MAX.overflowing_add(1));")] + /// ``` + #[unstable(feature = "bigint_helper_methods", issue = "85532")] + #[rustc_const_unstable(feature = "const_bigint_helper_methods", issue = "85532")] + #[must_use = "this returns the result of the operation, \ + without modifying the original"] + #[inline] + pub const fn carrying_add(self, rhs: Self, carry: bool) -> (Self, bool) { + // note: longer-term this should be done via an intrinsic. + // note: no intermediate overflow is required (https://github.com/rust-lang/rust/issues/85532#issuecomment-1032214946). + let (a, b) = self.overflowing_add(rhs); + let (c, d) = a.overflowing_add(carry as $SelfT); + (c, b != d) + } + /// Calculates `self` + `rhs` with an unsigned `rhs` /// /// Returns a tuple of the addition along with a boolean indicating @@ -1569,6 +1614,39 @@ macro_rules! int_impl { (a as Self, b) } + /// Calculates `self - rhs - borrow` without the ability to overflow. + /// + /// Performs "signed ternary subtraction" which takes in an extra bit to subtract, and may return an + /// additional bit of overflow. This signed function is used only on the highest-ordered data, + /// for which the signed overflow result indicates whether the big integer overflowed or not. + /// + /// # Examples + /// + /// Basic usage: + /// + /// ``` + /// #![feature(bigint_helper_methods)] + #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".borrowing_sub(2, false), (3, false));")] + #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".borrowing_sub(2, true), (2, false));")] + #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".borrowing_sub(1, false), (-1, false));")] + #[doc = concat!("assert_eq!(0", stringify!($SelfT), ".borrowing_sub(1, true), (-2, false));")] + #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MIN.borrowing_sub(1, true), (", stringify!($SelfT), "::MAX - 1, true));")] + #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.borrowing_sub(-1, false), (", stringify!($SelfT), "::MIN, true));")] + #[doc = concat!("assert_eq!(", stringify!($SelfT), "::MAX.borrowing_sub(-1, true), (", stringify!($SelfT), "::MAX, false));")] + /// ``` + #[unstable(feature = "bigint_helper_methods", issue = "85532")] + #[rustc_const_unstable(feature = "const_bigint_helper_methods", issue = "85532")] + #[must_use = "this returns the result of the operation, \ + without modifying the original"] + #[inline] + pub const fn borrowing_sub(self, rhs: Self, borrow: bool) -> (Self, bool) { + // note: longer-term this should be done via an intrinsic. + // note: no intermediate overflow is required (https://github.com/rust-lang/rust/issues/85532#issuecomment-1032214946). + let (a, b) = self.overflowing_sub(rhs); + let (c, d) = a.overflowing_sub(borrow as $SelfT); + (c, b != d) + } + /// Calculates `self` - `rhs` with an unsigned `rhs` /// /// Returns a tuple of the subtraction along with a boolean indicating @@ -2204,7 +2282,7 @@ macro_rules! int_impl { /// rounded down. /// /// This method might not be optimized owing to implementation details; - /// `log2` can produce results more efficiently for base 2, and `log10` + /// `ilog2` can produce results more efficiently for base 2, and `ilog10` /// can produce results more efficiently for base 10. /// /// # Panics @@ -2217,7 +2295,7 @@ macro_rules! int_impl { /// /// ``` /// #![feature(int_log)] - #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".log(5), 1);")] + #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".ilog(5), 1);")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ @@ -2226,8 +2304,8 @@ macro_rules! int_impl { #[track_caller] #[rustc_inherit_overflow_checks] #[allow(arithmetic_overflow)] - pub const fn log(self, base: Self) -> u32 { - match self.checked_log(base) { + pub const fn ilog(self, base: Self) -> u32 { + match self.checked_ilog(base) { Some(n) => n, None => { // In debug builds, trigger a panic on None. @@ -2250,7 +2328,7 @@ macro_rules! int_impl { /// /// ``` /// #![feature(int_log)] - #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".log2(), 1);")] + #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".ilog2(), 1);")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ @@ -2259,8 +2337,8 @@ macro_rules! int_impl { #[track_caller] #[rustc_inherit_overflow_checks] #[allow(arithmetic_overflow)] - pub const fn log2(self) -> u32 { - match self.checked_log2() { + pub const fn ilog2(self) -> u32 { + match self.checked_ilog2() { Some(n) => n, None => { // In debug builds, trigger a panic on None. @@ -2283,7 +2361,7 @@ macro_rules! int_impl { /// /// ``` /// #![feature(int_log)] - #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".log10(), 1);")] + #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".ilog10(), 1);")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ @@ -2292,8 +2370,8 @@ macro_rules! int_impl { #[track_caller] #[rustc_inherit_overflow_checks] #[allow(arithmetic_overflow)] - pub const fn log10(self) -> u32 { - match self.checked_log10() { + pub const fn ilog10(self) -> u32 { + match self.checked_ilog10() { Some(n) => n, None => { // In debug builds, trigger a panic on None. @@ -2311,20 +2389,20 @@ macro_rules! int_impl { /// Returns `None` if the number is negative or zero, or if the base is not at least 2. /// /// This method might not be optimized owing to implementation details; - /// `checked_log2` can produce results more efficiently for base 2, and - /// `checked_log10` can produce results more efficiently for base 10. + /// `checked_ilog2` can produce results more efficiently for base 2, and + /// `checked_ilog10` can produce results more efficiently for base 10. /// /// # Examples /// /// ``` /// #![feature(int_log)] - #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_log(5), Some(1));")] + #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_ilog(5), Some(1));")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] - pub const fn checked_log(self, base: Self) -> Option<u32> { + pub const fn checked_ilog(self, base: Self) -> Option<u32> { if self <= 0 || base <= 1 { None } else { @@ -2333,7 +2411,7 @@ macro_rules! int_impl { // Optimization for 128 bit wide integers. if Self::BITS == 128 { - let b = Self::log2(self) / (Self::log2(base) + 1); + let b = Self::ilog2(self) / (Self::ilog2(base) + 1); n += b; r /= base.pow(b as u32); } @@ -2354,13 +2432,13 @@ macro_rules! int_impl { /// /// ``` /// #![feature(int_log)] - #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_log2(), Some(1));")] + #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_ilog2(), Some(1));")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] - pub const fn checked_log2(self) -> Option<u32> { + pub const fn checked_ilog2(self) -> Option<u32> { if self <= 0 { None } else { @@ -2378,13 +2456,13 @@ macro_rules! int_impl { /// /// ``` /// #![feature(int_log)] - #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_log10(), Some(1));")] + #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_ilog10(), Some(1));")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] - pub const fn checked_log10(self) -> Option<u32> { + pub const fn checked_ilog10(self) -> Option<u32> { if self > 0 { Some(int_log10::$ActualT(self as $ActualT)) } else { diff --git a/library/core/src/num/mod.rs b/library/core/src/num/mod.rs index f481399fd..ab17aa0c8 100644 --- a/library/core/src/num/mod.rs +++ b/library/core/src/num/mod.rs @@ -3,6 +3,8 @@ #![stable(feature = "rust1", since = "1.0.0")] use crate::ascii; +#[cfg(not(bootstrap))] +use crate::error::Error; use crate::intrinsics; use crate::mem; use crate::ops::{Add, Mul, Sub}; @@ -57,6 +59,16 @@ pub use wrapping::Wrapping; #[cfg(not(no_fp_fmt_parse))] pub use dec2flt::ParseFloatError; +#[cfg(not(bootstrap))] +#[cfg(not(no_fp_fmt_parse))] +#[stable(feature = "rust1", since = "1.0.0")] +impl Error for ParseFloatError { + #[allow(deprecated)] + fn description(&self) -> &str { + self.__description() + } +} + #[stable(feature = "rust1", since = "1.0.0")] pub use error::ParseIntError; @@ -623,7 +635,7 @@ impl u8 { /// /// - U+0021 ..= U+002F `! " # $ % & ' ( ) * + , - . /`, or /// - U+003A ..= U+0040 `: ; < = > ? @`, or - /// - U+005B ..= U+0060 ``[ \ ] ^ _ ` ``, or + /// - U+005B ..= U+0060 `` [ \ ] ^ _ ` ``, or /// - U+007B ..= U+007E `{ | } ~` /// /// # Examples diff --git a/library/core/src/num/nonzero.rs b/library/core/src/num/nonzero.rs index 4de0a0cf5..532a09736 100644 --- a/library/core/src/num/nonzero.rs +++ b/library/core/src/num/nonzero.rs @@ -56,7 +56,7 @@ macro_rules! nonzero_integers { pub const unsafe fn new_unchecked(n: $Int) -> Self { // SAFETY: this is guaranteed to be safe by the caller. unsafe { - core::intrinsics::assert_unsafe_precondition!(n != 0); + core::intrinsics::assert_unsafe_precondition!((n: $Int) => n != 0); Self(n) } } @@ -309,8 +309,8 @@ macro_rules! nonzero_unsigned_operations { ( $( $Ty: ident($Int: ident); )+ ) => { $( impl $Ty { - /// Add an unsigned integer to a non-zero value. - /// Check for overflow and return [`None`] on overflow + /// Adds an unsigned integer to a non-zero value. + /// Checks for overflow and returns [`None`] on overflow. /// As a consequence, the result cannot wrap to zero. /// /// @@ -346,7 +346,7 @@ macro_rules! nonzero_unsigned_operations { } } - /// Add an unsigned integer to a non-zero value. + /// Adds an unsigned integer to a non-zero value. #[doc = concat!("Return [`", stringify!($Int), "::MAX`] on overflow.")] /// /// # Examples @@ -377,7 +377,7 @@ macro_rules! nonzero_unsigned_operations { unsafe { $Ty::new_unchecked(self.get().saturating_add(other)) } } - /// Add an unsigned integer to a non-zero value, + /// Adds an unsigned integer to a non-zero value, /// assuming overflow cannot occur. /// Overflow is unchecked, and it is undefined behaviour to overflow /// *even if the result would wrap to a non-zero value*. @@ -409,7 +409,7 @@ macro_rules! nonzero_unsigned_operations { } /// Returns the smallest power of two greater than or equal to n. - /// Check for overflow and return [`None`] + /// Checks for overflow and returns [`None`] /// if the next power of two is greater than the type’s maximum value. /// As a consequence, the result cannot wrap to zero. /// @@ -450,7 +450,7 @@ macro_rules! nonzero_unsigned_operations { /// Returns the base 2 logarithm of the number, rounded down. /// /// This is the same operation as - #[doc = concat!("[`", stringify!($Int), "::log2`],")] + #[doc = concat!("[`", stringify!($Int), "::ilog2`],")] /// except that it has no failure cases to worry about /// since this value can never be zero. /// @@ -460,22 +460,22 @@ macro_rules! nonzero_unsigned_operations { /// #![feature(int_log)] #[doc = concat!("# use std::num::", stringify!($Ty), ";")] /// - #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(7).unwrap().log2(), 2);")] - #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(8).unwrap().log2(), 3);")] - #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(9).unwrap().log2(), 3);")] + #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(7).unwrap().ilog2(), 2);")] + #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(8).unwrap().ilog2(), 3);")] + #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(9).unwrap().ilog2(), 3);")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] - pub const fn log2(self) -> u32 { + pub const fn ilog2(self) -> u32 { Self::BITS - 1 - self.leading_zeros() } /// Returns the base 10 logarithm of the number, rounded down. /// /// This is the same operation as - #[doc = concat!("[`", stringify!($Int), "::log10`],")] + #[doc = concat!("[`", stringify!($Int), "::ilog10`],")] /// except that it has no failure cases to worry about /// since this value can never be zero. /// @@ -485,15 +485,15 @@ macro_rules! nonzero_unsigned_operations { /// #![feature(int_log)] #[doc = concat!("# use std::num::", stringify!($Ty), ";")] /// - #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(99).unwrap().log10(), 1);")] - #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(100).unwrap().log10(), 2);")] - #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(101).unwrap().log10(), 2);")] + #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(99).unwrap().ilog10(), 1);")] + #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(100).unwrap().ilog10(), 2);")] + #[doc = concat!("assert_eq!(", stringify!($Ty), "::new(101).unwrap().ilog10(), 2);")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] - pub const fn log10(self) -> u32 { + pub const fn ilog10(self) -> u32 { super::int_log10::$Int(self.0) } } @@ -545,7 +545,7 @@ macro_rules! nonzero_signed_operations { } /// Checked absolute value. - /// Check for overflow and returns [`None`] if + /// Checks for overflow and returns [`None`] if #[doc = concat!("`self == ", stringify!($Int), "::MIN`.")] /// The result cannot be zero. /// @@ -740,8 +740,8 @@ macro_rules! nonzero_unsigned_signed_operations { ( $( $signedness:ident $Ty: ident($Int: ty); )+ ) => { $( impl $Ty { - /// Multiply two non-zero integers together. - /// Check for overflow and return [`None`] on overflow. + /// Multiplies two non-zero integers together. + /// Checks for overflow and returns [`None`] on overflow. /// As a consequence, the result cannot wrap to zero. /// /// # Examples @@ -777,7 +777,7 @@ macro_rules! nonzero_unsigned_signed_operations { } } - /// Multiply two non-zero integers together. + /// Multiplies two non-zero integers together. #[doc = concat!("Return [`", stringify!($Int), "::MAX`] on overflow.")] /// /// # Examples @@ -809,7 +809,7 @@ macro_rules! nonzero_unsigned_signed_operations { unsafe { $Ty::new_unchecked(self.get().saturating_mul(other.get())) } } - /// Multiply two non-zero integers together, + /// Multiplies two non-zero integers together, /// assuming overflow cannot occur. /// Overflow is unchecked, and it is undefined behaviour to overflow /// *even if the result would wrap to a non-zero value*. @@ -849,8 +849,8 @@ macro_rules! nonzero_unsigned_signed_operations { unsafe { $Ty::new_unchecked(self.get().unchecked_mul(other.get())) } } - /// Raise non-zero value to an integer power. - /// Check for overflow and return [`None`] on overflow. + /// Raises non-zero value to an integer power. + /// Checks for overflow and returns [`None`] on overflow. /// As a consequence, the result cannot wrap to zero. /// /// # Examples diff --git a/library/core/src/num/uint_macros.rs b/library/core/src/num/uint_macros.rs index 733655442..46fd7f2d0 100644 --- a/library/core/src/num/uint_macros.rs +++ b/library/core/src/num/uint_macros.rs @@ -688,7 +688,7 @@ macro_rules! uint_impl { /// rounded down. /// /// This method might not be optimized owing to implementation details; - /// `log2` can produce results more efficiently for base 2, and `log10` + /// `ilog2` can produce results more efficiently for base 2, and `ilog10` /// can produce results more efficiently for base 10. /// /// # Panics @@ -700,7 +700,7 @@ macro_rules! uint_impl { /// /// ``` /// #![feature(int_log)] - #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".log(5), 1);")] + #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".ilog(5), 1);")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ @@ -709,8 +709,8 @@ macro_rules! uint_impl { #[track_caller] #[rustc_inherit_overflow_checks] #[allow(arithmetic_overflow)] - pub const fn log(self, base: Self) -> u32 { - match self.checked_log(base) { + pub const fn ilog(self, base: Self) -> u32 { + match self.checked_ilog(base) { Some(n) => n, None => { // In debug builds, trigger a panic on None. @@ -733,7 +733,7 @@ macro_rules! uint_impl { /// /// ``` /// #![feature(int_log)] - #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".log2(), 1);")] + #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".ilog2(), 1);")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ @@ -742,8 +742,8 @@ macro_rules! uint_impl { #[track_caller] #[rustc_inherit_overflow_checks] #[allow(arithmetic_overflow)] - pub const fn log2(self) -> u32 { - match self.checked_log2() { + pub const fn ilog2(self) -> u32 { + match self.checked_ilog2() { Some(n) => n, None => { // In debug builds, trigger a panic on None. @@ -766,7 +766,7 @@ macro_rules! uint_impl { /// /// ``` /// #![feature(int_log)] - #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".log10(), 1);")] + #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".ilog10(), 1);")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ @@ -775,8 +775,8 @@ macro_rules! uint_impl { #[track_caller] #[rustc_inherit_overflow_checks] #[allow(arithmetic_overflow)] - pub const fn log10(self) -> u32 { - match self.checked_log10() { + pub const fn ilog10(self) -> u32 { + match self.checked_ilog10() { Some(n) => n, None => { // In debug builds, trigger a panic on None. @@ -794,20 +794,20 @@ macro_rules! uint_impl { /// Returns `None` if the number is zero, or if the base is not at least 2. /// /// This method might not be optimized owing to implementation details; - /// `checked_log2` can produce results more efficiently for base 2, and - /// `checked_log10` can produce results more efficiently for base 10. + /// `checked_ilog2` can produce results more efficiently for base 2, and + /// `checked_ilog10` can produce results more efficiently for base 10. /// /// # Examples /// /// ``` /// #![feature(int_log)] - #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_log(5), Some(1));")] + #[doc = concat!("assert_eq!(5", stringify!($SelfT), ".checked_ilog(5), Some(1));")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] - pub const fn checked_log(self, base: Self) -> Option<u32> { + pub const fn checked_ilog(self, base: Self) -> Option<u32> { if self <= 0 || base <= 1 { None } else { @@ -816,7 +816,7 @@ macro_rules! uint_impl { // Optimization for 128 bit wide integers. if Self::BITS == 128 { - let b = Self::log2(self) / (Self::log2(base) + 1); + let b = Self::ilog2(self) / (Self::ilog2(base) + 1); n += b; r /= base.pow(b as u32); } @@ -837,15 +837,15 @@ macro_rules! uint_impl { /// /// ``` /// #![feature(int_log)] - #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_log2(), Some(1));")] + #[doc = concat!("assert_eq!(2", stringify!($SelfT), ".checked_ilog2(), Some(1));")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] - pub const fn checked_log2(self) -> Option<u32> { + pub const fn checked_ilog2(self) -> Option<u32> { if let Some(x) = <$NonZeroT>::new(self) { - Some(x.log2()) + Some(x.ilog2()) } else { None } @@ -859,15 +859,15 @@ macro_rules! uint_impl { /// /// ``` /// #![feature(int_log)] - #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_log10(), Some(1));")] + #[doc = concat!("assert_eq!(10", stringify!($SelfT), ".checked_ilog10(), Some(1));")] /// ``` #[unstable(feature = "int_log", issue = "70887")] #[must_use = "this returns the result of the operation, \ without modifying the original"] #[inline] - pub const fn checked_log10(self) -> Option<u32> { + pub const fn checked_ilog10(self) -> Option<u32> { if let Some(x) = <$NonZeroT>::new(self) { - Some(x.log10()) + Some(x.ilog10()) } else { None } |