Don't use direct field access in Simd functions

This commit is contained in:
Markus Everling 2023-04-22 21:12:35 +00:00
parent ceb2611592
commit afad9c3f64
2 changed files with 20 additions and 8 deletions

View File

@ -1,6 +1,8 @@
#![no_std] #![no_std]
#![feature( #![feature(
const_ptr_read, const_ptr_read,
const_refs_to_cell,
const_transmute_copy,
convert_float_to_int, convert_float_to_int,
decl_macro, decl_macro,
intra_doc_pointers, intra_doc_pointers,

View File

@ -135,22 +135,32 @@ impl<const LANES: usize> Swizzle<1, LANES> for Splat {
/// assert_eq!(v.as_array(), &[0, 1, 2, 3]); /// assert_eq!(v.as_array(), &[0, 1, 2, 3]);
/// ``` /// ```
pub const fn as_array(&self) -> &[T; LANES] { pub const fn as_array(&self) -> &[T; LANES] {
&self.0 // SAFETY: Transmuting between `Simd<T, LANES>` and `[T; LANES]`
// is always valid and `Simd<T, LANES>` never has a lower alignment
// than `[T; LANES]`.
unsafe { &*(self as *const Self as *const [T; LANES]) }
} }
/// Returns a mutable array reference containing the entire SIMD vector. /// Returns a mutable array reference containing the entire SIMD vector.
pub fn as_mut_array(&mut self) -> &mut [T; LANES] { pub fn as_mut_array(&mut self) -> &mut [T; LANES] {
&mut self.0 // SAFETY: Transmuting between `Simd<T, LANES>` and `[T; LANES]`
// is always valid and `Simd<T, LANES>` never has a lower alignment
// than `[T; LANES]`.
unsafe { &mut *(self as *mut Self as *mut [T; LANES]) }
} }
/// Converts an array to a SIMD vector. /// Converts an array to a SIMD vector.
pub const fn from_array(array: [T; LANES]) -> Self { pub const fn from_array(array: [T; LANES]) -> Self {
Self(array) // SAFETY: Transmuting between `Simd<T, LANES>` and `[T; LANES]`
// is always valid.
unsafe { core::mem::transmute_copy(&array) }
} }
/// Converts a SIMD vector to an array. /// Converts a SIMD vector to an array.
pub const fn to_array(self) -> [T; LANES] { pub const fn to_array(self) -> [T; LANES] {
self.0 // SAFETY: Transmuting between `Simd<T, LANES>` and `[T; LANES]`
// is always valid.
unsafe { core::mem::transmute_copy(&self) }
} }
/// Converts a slice to a SIMD vector containing `slice[..LANES]`. /// Converts a slice to a SIMD vector containing `slice[..LANES]`.
@ -735,7 +745,7 @@ fn hash<H>(&self, state: &mut H)
{ {
#[inline] #[inline]
fn as_ref(&self) -> &[T; LANES] { fn as_ref(&self) -> &[T; LANES] {
&self.0 self.as_array()
} }
} }
@ -746,7 +756,7 @@ fn hash<H>(&self, state: &mut H)
{ {
#[inline] #[inline]
fn as_mut(&mut self) -> &mut [T; LANES] { fn as_mut(&mut self) -> &mut [T; LANES] {
&mut self.0 self.as_mut_array()
} }
} }
@ -758,7 +768,7 @@ impl<T, const LANES: usize> AsRef<[T]> for Simd<T, LANES>
{ {
#[inline] #[inline]
fn as_ref(&self) -> &[T] { fn as_ref(&self) -> &[T] {
&self.0 self.as_array()
} }
} }
@ -769,7 +779,7 @@ impl<T, const LANES: usize> AsMut<[T]> for Simd<T, LANES>
{ {
#[inline] #[inline]
fn as_mut(&mut self) -> &mut [T] { fn as_mut(&mut self) -> &mut [T] {
&mut self.0 self.as_mut_array()
} }
} }