2 // Tests saturating float->int casts. See u128-as-f32.rs for the opposite direction.
3 // compile-flags: -Z saturating-float-casts
5 #![feature(test, stmt_expr_attributes)]
6 #![deny(overflowing_literals)]
10 use std::{u8, i8, u16, i16, u32, i32, u64, i64};
11 #[cfg(not(target_os="emscripten"))]
12 use std::{u128, i128};
16 ($val:expr, $src_ty:ident -> $dest_ty:ident, $expected:expr) => (
17 // black_box disables constant evaluation to test run-time conversions:
18 assert_eq!(black_box::<$src_ty>($val) as $dest_ty, $expected,
19 "run-time {} -> {}", stringify!($src_ty), stringify!($dest_ty));
22 ($fval:expr, f* -> $ity:ident, $ival:expr) => (
23 test!($fval, f32 -> $ity, $ival);
24 test!($fval, f64 -> $ity, $ival);
28 // This macro tests const eval in addition to run-time evaluation.
29 // If and when saturating casts are adopted, this macro should be merged with test!() to ensure
30 // that run-time and const eval agree on inputs that currently trigger a const eval error.
32 ($val:expr, $src_ty:ident -> $dest_ty:ident, $expected:expr) => ({
33 test!($val, $src_ty -> $dest_ty, $expected);
35 const X: $src_ty = $val;
36 const Y: $dest_ty = X as $dest_ty;
37 assert_eq!(Y, $expected,
38 "const eval {} -> {}", stringify!($src_ty), stringify!($dest_ty));
42 ($fval:expr, f* -> $ity:ident, $ival:expr) => (
43 test_c!($fval, f32 -> $ity, $ival);
44 test_c!($fval, f64 -> $ity, $ival);
48 macro_rules! common_fptoi_tests {
49 ($fty:ident -> $($ity:ident)+) => ({ $(
50 test!($fty::NAN, $fty -> $ity, 0);
51 test!($fty::INFINITY, $fty -> $ity, $ity::MAX);
52 test!($fty::NEG_INFINITY, $fty -> $ity, $ity::MIN);
53 // These two tests are not solely float->int tests, in particular the latter relies on
54 // `u128::MAX as f32` not being UB. But that's okay, since this file tests int->float
55 // as well, the test is just slightly misplaced.
56 test!($ity::MIN as $fty, $fty -> $ity, $ity::MIN);
57 test!($ity::MAX as $fty, $fty -> $ity, $ity::MAX);
58 test_c!(0., $fty -> $ity, 0);
59 test_c!($fty::MIN_POSITIVE, $fty -> $ity, 0);
60 test!(-0.9, $fty -> $ity, 0);
61 test_c!(1., $fty -> $ity, 1);
62 test_c!(42., $fty -> $ity, 42);
65 (f* -> $($ity:ident)+) => ({
66 common_fptoi_tests!(f32 -> $($ity)+);
67 common_fptoi_tests!(f64 -> $($ity)+);
71 macro_rules! fptoui_tests {
72 ($fty: ident -> $($ity: ident)+) => ({ $(
73 test!(-0., $fty -> $ity, 0);
74 test!(-$fty::MIN_POSITIVE, $fty -> $ity, 0);
75 test!(-0.99999994, $fty -> $ity, 0);
76 test!(-1., $fty -> $ity, 0);
77 test!(-100., $fty -> $ity, 0);
78 test!(#[allow(overflowing_literals)] -1e50, $fty -> $ity, 0);
79 test!(#[allow(overflowing_literals)] -1e130, $fty -> $ity, 0);
82 (f* -> $($ity:ident)+) => ({
83 fptoui_tests!(f32 -> $($ity)+);
84 fptoui_tests!(f64 -> $($ity)+);
89 common_fptoi_tests!(f* -> i8 i16 i32 i64 u8 u16 u32 u64);
90 fptoui_tests!(f* -> u8 u16 u32 u64);
91 // FIXME emscripten does not support i128
92 #[cfg(not(target_os="emscripten"))] {
93 common_fptoi_tests!(f* -> i128 u128);
94 fptoui_tests!(f* -> u128);
97 // The following tests cover edge cases for some integer types.
100 test_c!(254., f* -> u8, 254);
101 test!(256., f* -> u8, 255);
104 test_c!(-127., f* -> i8, -127);
105 test!(-129., f* -> i8, -128);
106 test_c!(126., f* -> i8, 126);
107 test!(128., f* -> i8, 127);
110 // -2147483648. is i32::MIN (exactly)
111 test_c!(-2147483648., f* -> i32, i32::MIN);
112 // 2147483648. is i32::MAX rounded up
113 test!(2147483648., f32 -> i32, 2147483647);
114 // With 24 significand bits, floats with magnitude in [2^30 + 1, 2^31] are rounded to
115 // multiples of 2^7. Therefore, nextDown(round(i32::MAX)) is 2^31 - 128:
116 test_c!(2147483520., f32 -> i32, 2147483520);
117 // Similarly, nextUp(i32::MIN) is i32::MIN + 2^8 and nextDown(i32::MIN) is i32::MIN - 2^7
118 test!(-2147483904., f* -> i32, i32::MIN);
119 test_c!(-2147483520., f* -> i32, -2147483520);
122 // round(MAX) and nextUp(round(MAX))
123 test_c!(4294967040., f* -> u32, 4294967040);
124 test!(4294967296., f* -> u32, 4294967295);
127 #[cfg(not(target_os="emscripten"))]
130 test_c!(f32::MAX, f32 -> u128, 0xffffff00000000000000000000000000);
131 // nextDown(f32::MAX) = 2^128 - 2 * 2^104
132 const SECOND_LARGEST_F32: f32 = 340282326356119256160033759537265639424.;
133 test_c!(SECOND_LARGEST_F32, f32 -> u128, 0xfffffe00000000000000000000000000);