X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=src%2Flibcore%2Fnum%2Ff32.rs;h=cb28035682d650607409d522448243413a03630b;hb=fe7227f6c8704f0186091085a14fd1027920e4bb;hp=07b05f91f489f9ecfa3752b2175e5f0bc35a3251;hpb=5e18b4bad8450622aef8e077d3470f5626403588;p=rust.git diff --git a/src/libcore/num/f32.rs b/src/libcore/num/f32.rs index 07b05f91f48..cb28035682d 100644 --- a/src/libcore/num/f32.rs +++ b/src/libcore/num/f32.rs @@ -61,13 +61,13 @@ /// Not a Number (NaN). #[stable(feature = "rust1", since = "1.0.0")] -pub const NAN: f32 = 0.0_f32/0.0_f32; +pub const NAN: f32 = 0.0_f32 / 0.0_f32; /// Infinity (∞). #[stable(feature = "rust1", since = "1.0.0")] -pub const INFINITY: f32 = 1.0_f32/0.0_f32; +pub const INFINITY: f32 = 1.0_f32 / 0.0_f32; /// Negative infinity (-∞). #[stable(feature = "rust1", since = "1.0.0")] -pub const NEG_INFINITY: f32 = -1.0_f32/0.0_f32; +pub const NEG_INFINITY: f32 = -1.0_f32 / 0.0_f32; /// Basic mathematical constants. #[stable(feature = "rust1", since = "1.0.0")] @@ -143,27 +143,11 @@ pub mod consts { reason = "stable interface is via `impl f{32,64}` in later crates", issue = "32110")] impl Float for f32 { - #[inline] - fn nan() -> f32 { NAN } - - #[inline] - fn infinity() -> f32 { INFINITY } - - #[inline] - fn neg_infinity() -> f32 { NEG_INFINITY } - - #[inline] - fn zero() -> f32 { 0.0 } - - #[inline] - fn neg_zero() -> f32 { -0.0 } - - #[inline] - fn one() -> f32 { 1.0 } - /// Returns `true` if the number is NaN. #[inline] - fn is_nan(self) -> bool { self != self } + fn is_nan(self) -> bool { + self != self + } /// Returns `true` if the number is infinite. #[inline] @@ -192,29 +176,14 @@ fn classify(self) -> Fp { let bits: u32 = unsafe { mem::transmute(self) }; match (bits & MAN_MASK, bits & EXP_MASK) { - (0, 0) => Fp::Zero, - (_, 0) => Fp::Subnormal, + (0, 0) => Fp::Zero, + (_, 0) => Fp::Subnormal, (0, EXP_MASK) => Fp::Infinite, (_, EXP_MASK) => Fp::Nan, - _ => Fp::Normal, + _ => Fp::Normal, } } - /// Returns the mantissa, exponent and sign as integers. - fn integer_decode(self) -> (u64, i16, i8) { - let bits: u32 = unsafe { mem::transmute(self) }; - let sign: i8 = if bits >> 31 == 0 { 1 } else { -1 }; - let mut exponent: i16 = ((bits >> 23) & 0xff) as i16; - let mantissa = if exponent == 0 { - (bits & 0x7fffff) << 1 - } else { - (bits & 0x7fffff) | 0x800000 - }; - // Exponent bias + mantissa shift - exponent -= 127 + 23; - (mantissa as u64, exponent, sign) - } - /// Computes the absolute value of `self`. Returns `Float::nan()` if the /// number is `Float::nan()`. #[inline] @@ -252,7 +221,9 @@ fn is_sign_negative(self) -> bool { /// Returns the reciprocal (multiplicative inverse) of the number. #[inline] - fn recip(self) -> f32 { 1.0 / self } + fn recip(self) -> f32 { + 1.0 / self + } #[inline] fn powi(self, n: i32) -> f32 { @@ -261,7 +232,9 @@ fn powi(self, n: i32) -> f32 { /// Converts to degrees, assuming the number is in radians. #[inline] - fn to_degrees(self) -> f32 { self * (180.0f32 / consts::PI) } + fn to_degrees(self) -> f32 { + self * (180.0f32 / consts::PI) + } /// Converts to radians, assuming the number is in degrees. #[inline] @@ -269,4 +242,32 @@ fn to_radians(self) -> f32 { let value: f32 = consts::PI; self * (value / 180.0f32) } + + /// Returns the maximum of the two numbers. + #[inline] + fn max(self, other: f32) -> f32 { + // IEEE754 says: maxNum(x, y) is the canonicalized number y if x < y, x if y < x, the + // canonicalized number if one operand is a number and the other a quiet NaN. Otherwise it + // is either x or y, canonicalized (this means results might differ among implementations). + // When either x or y is a signalingNaN, then the result is according to 6.2. + // + // Since we do not support sNaN in Rust yet, we do not need to handle them. + // FIXME(nagisa): due to https://bugs.llvm.org/show_bug.cgi?id=33303 we canonicalize by + // multiplying by 1.0. Should switch to the `canonicalize` when it works. + (if self < other || self.is_nan() { other } else { self }) * 1.0 + } + + /// Returns the minimum of the two numbers. + #[inline] + fn min(self, other: f32) -> f32 { + // IEEE754 says: minNum(x, y) is the canonicalized number x if x < y, y if y < x, the + // canonicalized number if one operand is a number and the other a quiet NaN. Otherwise it + // is either x or y, canonicalized (this means results might differ among implementations). + // When either x or y is a signalingNaN, then the result is according to 6.2. + // + // Since we do not support sNaN in Rust yet, we do not need to handle them. + // FIXME(nagisa): due to https://bugs.llvm.org/show_bug.cgi?id=33303 we canonicalize by + // multiplying by 1.0. Should switch to the `canonicalize` when it works. + (if self < other || other.is_nan() { self } else { other }) * 1.0 + } }