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Merge pull request #501 from folkertdev/simd-splat-intrinsic

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use `intrinsics::simd::simd_splat`
This commit is contained in:
Jacob Lifshay 2026-01-26 13:22:58 -08:00 • committed by GitHub
commit e3d85fb0ad
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GPG key ID: B5690EEEBB952194
2 changed files with 21 additions and 27 deletions
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46
crates/core_simd/src/vector.rs
View file

@ -1,5 +1,7 @@
use core::intrinsics::simd::SimdAlign;
use crate::simd::{
Mask, MaskElement, Swizzle,
Mask, MaskElement,
cmp::SimdPartialOrd,
num::SimdUint,
ptr::{SimdConstPtr, SimdMutPtr},
@ -147,28 +149,8 @@ where
#[inline]
#[rustc_const_unstable(feature = "portable_simd", issue = "86656")]
pub const fn splat(value: T) -> Self {
const fn splat_const<T, const N: usize>(value: T) -> Simd<T, N>
where
T: SimdElement,
{
Simd::from_array([value; N])
}
fn splat_rt<T, const N: usize>(value: T) -> Simd<T, N>
where
T: SimdElement,
{
// This is preferred over `[value; N]`, since it's explicitly a splat:
// https://github.com/rust-lang/rust/issues/97804
struct Splat;
impl<const N: usize> Swizzle<N> for Splat {
const INDEX: [usize; N] = [0; N];
}
Splat::swizzle::<T, 1>(Simd::<T, 1>::from([value]))
}
core::intrinsics::const_eval_select((value,), splat_const, splat_rt)
// SAFETY: T is a SimdElement, and the item type of Self.
unsafe { core::intrinsics::simd::simd_splat(value) }
}
/// Returns an array reference containing the entire SIMD vector.
@ -464,7 +446,7 @@ where
/// value from `or` is passed through.
///
/// # Safety
/// Enabled `ptr` elements must be safe to read as if by `std::ptr::read`.
/// Enabled `ptr` elements must be safe to read as if by `core::ptr::read`.
#[must_use]
#[inline]
pub unsafe fn load_select_ptr(
@ -473,7 +455,13 @@ where
or: Self,
) -> Self {
// SAFETY: The safety of reading elements through `ptr` is ensured by the caller.
unsafe { core::intrinsics::simd::simd_masked_load(enable.to_simd(), ptr, or) }
unsafe {
core::intrinsics::simd::simd_masked_load::<_, _, _, { SimdAlign::Element }>(
enable.to_simd(),
ptr,
or,
)
}
}
/// Reads from potentially discontiguous indices in `slice` to construct a SIMD vector.
@ -722,7 +710,13 @@ where
#[inline]
pub unsafe fn store_select_ptr(self, ptr: *mut T, enable: Mask<<T as SimdElement>::Mask, N>) {
// SAFETY: The safety of writing elements through `ptr` is ensured by the caller.
unsafe { core::intrinsics::simd::simd_masked_store(enable.to_simd(), ptr, self) }
unsafe {
core::intrinsics::simd::simd_masked_store::<_, _, _, { SimdAlign::Element }>(
enable.to_simd(),
ptr,
self,
)
}
}
/// Writes the values in a SIMD vector to potentially discontiguous indices in `slice`.

2
rust-toolchain.toml
View file

@ -1,3 +1,3 @@
[toolchain]
channel = "nightly-2025-09-30"
channel = "nightly-2026-01-26"
components = ["rustfmt", "clippy", "miri", "rust-src"]