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//@ compile-flags: -Zmir-opt-level=0
//@ run-pass
// This tests the float classification functions, for regular runtime code and for const evaluation.
#![feature(f16)]
#![feature(f128)]
#![allow(unused_macro_rules)]
use std::hint::black_box;
macro_rules! both_assert {
($a:expr) => {
{
const _: () = assert!($a);
// `black_box` prevents promotion, and MIR opts are disabled above, so this is truly
// going through LLVM.
assert!(black_box($a));
}
};
($a:expr, $b:expr) => {
{
const _: () = assert!($a == $b);
assert_eq!(black_box($a), black_box($b));
}
};
}
fn has_broken_floats() -> bool {
// i586 targets are broken due to <https://github.com/rust-lang/rust/issues/114479>.
cfg!(all(target_arch = "x86", not(target_feature = "sse2")))
}
#[cfg(target_arch = "x86_64")]
fn f16(){
both_assert!((1f16).to_bits(), 0x3c00);
both_assert!(u16::from_be_bytes(1f16.to_be_bytes()), 0x3c00);
both_assert!((12.5f16).to_bits(), 0x4a40);
both_assert!(u16::from_le_bytes(12.5f16.to_le_bytes()), 0x4a40);
both_assert!((1337f16).to_bits(), 0x6539);
both_assert!(u16::from_ne_bytes(1337f16.to_ne_bytes()), 0x6539);
both_assert!((-14.25f16).to_bits(), 0xcb20);
both_assert!(f16::from_bits(0x3c00), 1.0);
both_assert!(f16::from_be_bytes(0x3c00u16.to_be_bytes()), 1.0);
both_assert!(f16::from_bits(0x4a40), 12.5);
both_assert!(f16::from_le_bytes(0x4a40u16.to_le_bytes()), 12.5);
both_assert!(f16::from_bits(0x5be0), 252.0);
both_assert!(f16::from_ne_bytes(0x5be0u16.to_ne_bytes()), 252.0);
both_assert!(f16::from_bits(0xcb20), -14.25);
// Check that NaNs roundtrip their bits regardless of signalingness
// 0xA is 0b1010; 0x5 is 0b0101 -- so these two together clobbers all the mantissa bits
// NOTE: These names assume `f{BITS}::NAN` is a quiet NAN and IEEE754-2008's NaN rules apply!
const QUIET_NAN: u16 = f16::NAN.to_bits() ^ 0x0155;
const SIGNALING_NAN: u16 = f16::NAN.to_bits() ^ 0x02AA;
both_assert!(f16::from_bits(QUIET_NAN).is_nan());
both_assert!(f16::from_bits(SIGNALING_NAN).is_nan());
both_assert!(f16::from_bits(QUIET_NAN).to_bits(), QUIET_NAN);
if !has_broken_floats() {
both_assert!(f16::from_bits(SIGNALING_NAN).to_bits(), SIGNALING_NAN);
}
}
fn f32() {
both_assert!((1f32).to_bits(), 0x3f800000);
both_assert!(u32::from_be_bytes(1f32.to_be_bytes()), 0x3f800000);
both_assert!((12.5f32).to_bits(), 0x41480000);
both_assert!(u32::from_le_bytes(12.5f32.to_le_bytes()), 0x41480000);
both_assert!((1337f32).to_bits(), 0x44a72000);
both_assert!(u32::from_ne_bytes(1337f32.to_ne_bytes()), 0x44a72000);
both_assert!((-14.25f32).to_bits(), 0xc1640000);
both_assert!(f32::from_bits(0x3f800000), 1.0);
both_assert!(f32::from_be_bytes(0x3f800000u32.to_be_bytes()), 1.0);
both_assert!(f32::from_bits(0x41480000), 12.5);
both_assert!(f32::from_le_bytes(0x41480000u32.to_le_bytes()), 12.5);
both_assert!(f32::from_bits(0x44a72000), 1337.0);
both_assert!(f32::from_ne_bytes(0x44a72000u32.to_ne_bytes()), 1337.0);
both_assert!(f32::from_bits(0xc1640000), -14.25);
// Check that NaNs roundtrip their bits regardless of signalingness
// 0xA is 0b1010; 0x5 is 0b0101 -- so these two together clobbers all the mantissa bits
// NOTE: These names assume `f{BITS}::NAN` is a quiet NAN and IEEE754-2008's NaN rules apply!
const QUIET_NAN: u32 = f32::NAN.to_bits() ^ 0x002A_AAAA;
const SIGNALING_NAN: u32 = f32::NAN.to_bits() ^ 0x0055_5555;
both_assert!(f32::from_bits(QUIET_NAN).is_nan());
both_assert!(f32::from_bits(SIGNALING_NAN).is_nan());
both_assert!(f32::from_bits(QUIET_NAN).to_bits(), QUIET_NAN);
if !has_broken_floats() {
both_assert!(f32::from_bits(SIGNALING_NAN).to_bits(), SIGNALING_NAN);
}
}
fn f64() {
both_assert!((1f64).to_bits(), 0x3ff0000000000000);
both_assert!(u64::from_be_bytes(1f64.to_be_bytes()), 0x3ff0000000000000);
both_assert!((12.5f64).to_bits(), 0x4029000000000000);
both_assert!(u64::from_le_bytes(12.5f64.to_le_bytes()), 0x4029000000000000);
both_assert!((1337f64).to_bits(), 0x4094e40000000000);
both_assert!(u64::from_ne_bytes(1337f64.to_ne_bytes()), 0x4094e40000000000);
both_assert!((-14.25f64).to_bits(), 0xc02c800000000000);
both_assert!(f64::from_bits(0x3ff0000000000000), 1.0);
both_assert!(f64::from_be_bytes(0x3ff0000000000000u64.to_be_bytes()), 1.0);
both_assert!(f64::from_bits(0x4029000000000000), 12.5);
both_assert!(f64::from_le_bytes(0x4029000000000000u64.to_le_bytes()), 12.5);
both_assert!(f64::from_bits(0x4094e40000000000), 1337.0);
both_assert!(f64::from_ne_bytes(0x4094e40000000000u64.to_ne_bytes()), 1337.0);
both_assert!(f64::from_bits(0xc02c800000000000), -14.25);
// Check that NaNs roundtrip their bits regardless of signalingness
// 0xA is 0b1010; 0x5 is 0b0101 -- so these two together clobbers all the mantissa bits
// NOTE: These names assume `f{BITS}::NAN` is a quiet NAN and IEEE754-2008's NaN rules apply!
const QUIET_NAN: u64 = f64::NAN.to_bits() ^ 0x0005_5555_5555_5555;
const SIGNALING_NAN: u64 = f64::NAN.to_bits() ^ 0x000A_AAAA_AAAA_AAAA;
both_assert!(f64::from_bits(QUIET_NAN).is_nan());
both_assert!(f64::from_bits(SIGNALING_NAN).is_nan());
both_assert!(f64::from_bits(QUIET_NAN).to_bits(), QUIET_NAN);
if !has_broken_floats() {
both_assert!(f64::from_bits(SIGNALING_NAN).to_bits(), SIGNALING_NAN);
}
}
#[cfg(target_arch = "x86_64")]
fn f128() {
both_assert!((1f128).to_bits(), 0x3fff0000000000000000000000000000);
both_assert!(u128::from_be_bytes(1f128.to_be_bytes()), 0x3fff0000000000000000000000000000);
both_assert!((12.5f128).to_bits(), 0x40029000000000000000000000000000);
both_assert!(u128::from_le_bytes(12.5f128.to_le_bytes()), 0x40029000000000000000000000000000);
both_assert!((1337f128).to_bits(), 0x40094e40000000000000000000000000);
both_assert!(u128::from_ne_bytes(1337f128.to_ne_bytes()), 0x40094e40000000000000000000000000);
both_assert!((-14.25f128).to_bits(), 0xc002c800000000000000000000000000);
both_assert!(f128::from_bits(0x3fff0000000000000000000000000000), 1.0);
both_assert!(f128::from_be_bytes(0x3fff0000000000000000000000000000u128.to_be_bytes()), 1.0);
both_assert!(f128::from_bits(0x40029000000000000000000000000000), 12.5);
both_assert!(f128::from_le_bytes(0x40029000000000000000000000000000u128.to_le_bytes()), 12.5);
both_assert!(f128::from_bits(0x40094e40000000000000000000000000), 1337.0);
assert_eq!(f128::from_ne_bytes(0x40094e40000000000000000000000000u128.to_ne_bytes()), 1337.0);
both_assert!(f128::from_bits(0xc002c800000000000000000000000000), -14.25);
// Check that NaNs roundtrip their bits regardless of signalingness
// 0xA is 0b1010; 0x5 is 0b0101 -- so these two together clobbers all the mantissa bits
// NOTE: These names assume `f{BITS}::NAN` is a quiet NAN and IEEE754-2008's NaN rules apply!
const QUIET_NAN: u128 = f128::NAN.to_bits() | 0x0000_AAAA_AAAA_AAAA_AAAA_AAAA_AAAA_AAAA;
const SIGNALING_NAN: u128 = f128::NAN.to_bits() ^ 0x0000_5555_5555_5555_5555_5555_5555_5555;
both_assert!(f128::from_bits(QUIET_NAN).is_nan());
both_assert!(f128::from_bits(SIGNALING_NAN).is_nan());
both_assert!(f128::from_bits(QUIET_NAN).to_bits(), QUIET_NAN);
if !has_broken_floats() {
both_assert!(f128::from_bits(SIGNALING_NAN).to_bits(), SIGNALING_NAN);
}
}
fn main() {
f32();
f64();
#[cfg(target_arch = "x86_64")]
{
f16();
f128();
}
}
|
