diff --git a/tests/run-pass/float.rs b/tests/run-pass/float.rs index fc513ead8dd8..3347b0a07c26 100644 --- a/tests/run-pass/float.rs +++ b/tests/run-pass/float.rs @@ -1,4 +1,4 @@ -#![feature(track_caller)] +#![feature(track_caller, stmt_expr_attributes)] use std::fmt::Debug; // Helper function to avoid promotion so that this tests "run-time" casts, not CTFE. @@ -78,6 +78,7 @@ fn test_both_cast(x: F, y: I) fn main() { basic(); casts(); + more_casts(); ops(); } @@ -334,3 +335,113 @@ fn ops() { assert_eq((-3.5_f64).copysign(-0.42), -3.5_f64); assert!(f64::NAN.copysign(1.0).is_nan()); } + +/// Tests taken from rustc test suite. +/// + +// Poor-man's black-box +#[inline(never)] +fn black_box(x: T) -> T { x } + +macro_rules! test { + ($val:expr, $src_ty:ident -> $dest_ty:ident, $expected:expr) => ( + // black_box disables constant evaluation to test run-time conversions: + assert_eq!(black_box::<$src_ty>($val) as $dest_ty, $expected, + "run-time {} -> {}", stringify!($src_ty), stringify!($dest_ty)); + + { + const X: $src_ty = $val; + const Y: $dest_ty = X as $dest_ty; + assert_eq!(Y, $expected, + "const eval {} -> {}", stringify!($src_ty), stringify!($dest_ty)); + } + ); + + ($fval:expr, f* -> $ity:ident, $ival:expr) => ( + test!($fval, f32 -> $ity, $ival); + test!($fval, f64 -> $ity, $ival); + ) +} + +macro_rules! common_fptoi_tests { + ($fty:ident -> $($ity:ident)+) => ({ $( + test!($fty::NAN, $fty -> $ity, 0); + test!($fty::INFINITY, $fty -> $ity, $ity::MAX); + test!($fty::NEG_INFINITY, $fty -> $ity, $ity::MIN); + // These two tests are not solely float->int tests, in particular the latter relies on + // `u128::MAX as f32` not being UB. But that's okay, since this file tests int->float + // as well, the test is just slightly misplaced. + test!($ity::MIN as $fty, $fty -> $ity, $ity::MIN); + test!($ity::MAX as $fty, $fty -> $ity, $ity::MAX); + test!(0., $fty -> $ity, 0); + test!($fty::MIN_POSITIVE, $fty -> $ity, 0); + test!(-0.9, $fty -> $ity, 0); + test!(1., $fty -> $ity, 1); + test!(42., $fty -> $ity, 42); + )+ }); + + (f* -> $($ity:ident)+) => ({ + common_fptoi_tests!(f32 -> $($ity)+); + common_fptoi_tests!(f64 -> $($ity)+); + }) +} + +macro_rules! fptoui_tests { + ($fty: ident -> $($ity: ident)+) => ({ $( + test!(-0., $fty -> $ity, 0); + test!(-$fty::MIN_POSITIVE, $fty -> $ity, 0); + test!(-0.99999994, $fty -> $ity, 0); + test!(-1., $fty -> $ity, 0); + test!(-100., $fty -> $ity, 0); + test!(#[allow(overflowing_literals)] -1e50, $fty -> $ity, 0); + test!(#[allow(overflowing_literals)] -1e130, $fty -> $ity, 0); + )+ }); + + (f* -> $($ity:ident)+) => ({ + fptoui_tests!(f32 -> $($ity)+); + fptoui_tests!(f64 -> $($ity)+); + }) +} + +fn more_casts() { + common_fptoi_tests!(f* -> i8 i16 i32 i64 u8 u16 u32 u64); + fptoui_tests!(f* -> u8 u16 u32 u64); + common_fptoi_tests!(f* -> i128 u128); + fptoui_tests!(f* -> u128); + + // The following tests cover edge cases for some integer types. + + // # u8 + test!(254., f* -> u8, 254); + test!(256., f* -> u8, 255); + + // # i8 + test!(-127., f* -> i8, -127); + test!(-129., f* -> i8, -128); + test!(126., f* -> i8, 126); + test!(128., f* -> i8, 127); + + // # i32 + // -2147483648. is i32::MIN (exactly) + test!(-2147483648., f* -> i32, i32::MIN); + // 2147483648. is i32::MAX rounded up + test!(2147483648., f32 -> i32, 2147483647); + // With 24 significand bits, floats with magnitude in [2^30 + 1, 2^31] are rounded to + // multiples of 2^7. Therefore, nextDown(round(i32::MAX)) is 2^31 - 128: + test!(2147483520., f32 -> i32, 2147483520); + // Similarly, nextUp(i32::MIN) is i32::MIN + 2^8 and nextDown(i32::MIN) is i32::MIN - 2^7 + test!(-2147483904., f* -> i32, i32::MIN); + test!(-2147483520., f* -> i32, -2147483520); + + // # u32 + // round(MAX) and nextUp(round(MAX)) + test!(4294967040., f* -> u32, 4294967040); + test!(4294967296., f* -> u32, 4294967295); + + // # u128 + // float->int: + test!(f32::MAX, f32 -> u128, 0xffffff00000000000000000000000000); + // nextDown(f32::MAX) = 2^128 - 2 * 2^104 + const SECOND_LARGEST_F32: f32 = 340282326356119256160033759537265639424.; + test!(SECOND_LARGEST_F32, f32 -> u128, 0xfffffe00000000000000000000000000); +}