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41 lines
1022 B
Rust
41 lines
1022 B
Rust
// run-pass
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// only-x86_64
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#![feature(const_eval_select)]
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#![feature(core_intrinsics)]
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use std::intrinsics::const_eval_select;
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use std::arch::x86_64::*;
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use std::mem::transmute;
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const fn eq_ct(x: [i32; 4], y: [i32; 4]) -> bool {
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x[0] == y[0] && x[1] == y[1] && x[2] == y[2] && x[3] == y[3]
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}
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fn eq_rt(x: [i32; 4], y: [i32; 4]) -> bool {
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unsafe {
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let x = _mm_loadu_si128(&x as *const _ as *const _);
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let y = _mm_loadu_si128(&y as *const _ as *const _);
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let r = _mm_cmpeq_epi32(x, y);
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let r = _mm_movemask_ps(transmute(r) );
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r == 0b1111
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}
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}
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const fn eq(x: [i32; 4], y: [i32; 4]) -> bool {
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unsafe {
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const_eval_select((x, y), eq_ct, eq_rt)
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}
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}
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fn main() {
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const X: bool = eq([0, 1, 2, 3], [0, 1, 2, 3]);
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assert_eq!(X, true);
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let x = eq([0, 1, 2, 3], [0, 1, 2, 3]);
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assert_eq!(x, true);
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const Y: bool = eq([0, 1, 2, 3], [0, 1, 3, 2]);
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assert_eq!(Y, false);
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let y = eq([0, 1, 2, 3], [0, 1, 3, 2]);
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assert_eq!(y, false);
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}
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