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simd_scatter/gather: test OOB cases and the order of writes

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This commit is contained in:
Ralf Jung 2023-12-22 12:03:54 +01:00
parent 23efae075a
commit 84304fc00a
1 changed files with 39 additions and 6 deletions
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45
src/tools/miri/tests/pass/portable-simd.rs
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@ -1,6 +1,8 @@
//@compile-flags: -Zmiri-strict-provenance
#![feature(portable_simd, platform_intrinsics, adt_const_params, inline_const)]
#![feature(portable_simd, platform_intrinsics, adt_const_params, inline_const, core_intrinsics)]
#![allow(incomplete_features, internal_features)]
use std::intrinsics::simd as intrinsics;
use std::ptr;
use std::simd::{prelude::*, StdFloat};
fn simd_ops_f32() {
@ -421,6 +423,40 @@ fn simd_gather_scatter() {
let idxs = Simd::from_array([9, 3, 0, 0]);
Simd::from_array([-27, 82, -41, 124]).scatter(&mut vec, idxs);
assert_eq!(vec, vec![124, 11, 12, 82, 14, 15, 16, 17, 18]);
// We call the intrinsics directly to experiment with dangling pointers and masks.
let val = 42u8;
let ptrs: Simd<*const u8, 4> =
Simd::from_array([ptr::null(), ptr::addr_of!(val), ptr::addr_of!(val), ptr::addr_of!(val)]);
let default = u8x4::splat(0);
let mask = i8x4::from_array([0, !0, 0, !0]);
let vals = unsafe { intrinsics::simd_gather(default, ptrs, mask) };
assert_eq!(vals, u8x4::from_array([0, 42, 0, 42]),);
let mut val1 = 0u8;
let mut val2 = 0u8;
let ptrs: Simd<*mut u8, 4> = Simd::from_array([
ptr::null_mut(),
ptr::addr_of_mut!(val1),
ptr::addr_of_mut!(val1),
ptr::addr_of_mut!(val2),
]);
let vals = u8x4::from_array([1, 2, 3, 4]);
unsafe { intrinsics::simd_scatter(vals, ptrs, mask) };
assert_eq!(val1, 2);
assert_eq!(val2, 4);
// Also check what happens when `scatter` has multiple overlapping pointers.
let mut val = 0u8;
let ptrs: Simd<*mut u8, 4> = Simd::from_array([
ptr::addr_of_mut!(val),
ptr::addr_of_mut!(val),
ptr::addr_of_mut!(val),
ptr::addr_of_mut!(val),
]);
let vals = u8x4::from_array([1, 2, 3, 4]);
unsafe { intrinsics::simd_scatter(vals, ptrs, mask) };
assert_eq!(val, 4);
}
fn simd_round() {
@ -460,14 +496,11 @@ fn simd_round() {
}
fn simd_intrinsics() {
use intrinsics::*;
extern "platform-intrinsic" {
fn simd_eq<T, U>(x: T, y: T) -> U;
fn simd_reduce_any<T>(x: T) -> bool;
fn simd_reduce_all<T>(x: T) -> bool;
fn simd_select<M, T>(m: M, yes: T, no: T) -> T;
fn simd_shuffle_generic<T, U, const IDX: &'static [u32]>(x: T, y: T) -> U;
fn simd_shuffle<T, IDX, U>(x: T, y: T, idx: IDX) -> U;
}
unsafe {
// Make sure simd_eq returns all-1 for `true`
let a = i32x4::splat(10);