Merge pull request #377 from rust-lang/bitmask-followup

Follow-up fixes for to_bitmask
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Caleb Zulawski 2023-11-19 10:47:32 -05:00 committed by GitHub
commit e0e9a4517f
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2 changed files with 47 additions and 50 deletions

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@ -295,6 +295,16 @@ pub fn from_bitmask(bitmask: u64) -> Self {
///
/// Each bit is set if the corresponding element in the mask is `true`.
/// The remaining bits are unset.
///
/// The bits are packed into the first N bits of the vector:
/// ```
/// # #![feature(portable_simd)]
/// # #[cfg(feature = "as_crate")] use core_simd::simd;
/// # #[cfg(not(feature = "as_crate"))] use core::simd;
/// # use simd::mask32x8;
/// let mask = mask32x8::from_array([true, false, true, false, false, false, true, false]);
/// assert_eq!(mask.to_bitmask_vector()[0], 0b01000101);
/// ```
#[inline]
#[must_use = "method returns a new integer and does not mutate the original value"]
pub fn to_bitmask_vector(self) -> Simd<u8, N> {
@ -304,6 +314,19 @@ pub fn to_bitmask_vector(self) -> Simd<u8, N> {
/// Create a mask from a bitmask vector.
///
/// For each bit, if it is set, the corresponding element in the mask is set to `true`.
///
/// The bits are packed into the first N bits of the vector:
/// ```
/// # #![feature(portable_simd)]
/// # #[cfg(feature = "as_crate")] use core_simd::simd;
/// # #[cfg(not(feature = "as_crate"))] use core::simd;
/// # use simd::{mask32x8, u8x8};
/// let bitmask = u8x8::from_array([0b01000101, 0, 0, 0, 0, 0, 0, 0]);
/// assert_eq!(
/// mask32x8::from_bitmask_vector(bitmask),
/// mask32x8::from_array([true, false, true, false, false, false, true, false]),
/// );
/// ```
#[inline]
#[must_use = "method returns a new mask and does not mutate the original value"]
pub fn from_bitmask_vector(bitmask: Simd<u8, N>) -> Self {

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@ -237,62 +237,36 @@ unsafe fn from_bitmask_impl<U: ReverseBits, const M: usize>(bitmask: U) -> Self
#[inline]
pub(crate) fn to_bitmask_integer(self) -> u64 {
// TODO modify simd_bitmask to zero-extend output, making this unnecessary
macro_rules! bitmask {
{ $($ty:ty: $($len:literal),*;)* } => {
match N {
$($(
// Safety: bitmask matches length
$len => unsafe { self.to_bitmask_impl::<$ty, $len>() as u64 },
)*)*
// Safety: bitmask matches length
_ => unsafe { self.to_bitmask_impl::<u64, 64>() },
}
}
}
#[cfg(all_lane_counts)]
bitmask! {
u8: 1, 2, 3, 4, 5, 6, 7, 8;
u16: 9, 10, 11, 12, 13, 14, 15, 16;
u32: 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32;
u64: 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64;
}
#[cfg(not(all_lane_counts))]
bitmask! {
u8: 1, 2, 4, 8;
u16: 16;
u32: 32;
u64: 64;
if N <= 8 {
// Safety: bitmask matches length
unsafe { self.to_bitmask_impl::<u8, 8>() as u64 }
} else if N <= 16 {
// Safety: bitmask matches length
unsafe { self.to_bitmask_impl::<u16, 16>() as u64 }
} else if N <= 32 {
// Safety: bitmask matches length
unsafe { self.to_bitmask_impl::<u32, 32>() as u64 }
} else {
// Safety: bitmask matches length
unsafe { self.to_bitmask_impl::<u64, 64>() }
}
}
#[inline]
pub(crate) fn from_bitmask_integer(bitmask: u64) -> Self {
// TODO modify simd_bitmask_select to truncate input, making this unnecessary
macro_rules! bitmask {
{ $($ty:ty: $($len:literal),*;)* } => {
match N {
$($(
// Safety: bitmask matches length
$len => unsafe { Self::from_bitmask_impl::<$ty, $len>(bitmask as $ty) },
)*)*
// Safety: bitmask matches length
_ => unsafe { Self::from_bitmask_impl::<u64, 64>(bitmask) },
}
}
}
#[cfg(all_lane_counts)]
bitmask! {
u8: 1, 2, 3, 4, 5, 6, 7, 8;
u16: 9, 10, 11, 12, 13, 14, 15, 16;
u32: 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32;
u64: 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64;
}
#[cfg(not(all_lane_counts))]
bitmask! {
u8: 1, 2, 4, 8;
u16: 16;
u32: 32;
u64: 64;
if N <= 8 {
// Safety: bitmask matches length
unsafe { Self::from_bitmask_impl::<u8, 8>(bitmask as u8) }
} else if N <= 16 {
// Safety: bitmask matches length
unsafe { Self::from_bitmask_impl::<u16, 16>(bitmask as u16) }
} else if N <= 32 {
// Safety: bitmask matches length
unsafe { Self::from_bitmask_impl::<u32, 32>(bitmask as u32) }
} else {
// Safety: bitmask matches length
unsafe { Self::from_bitmask_impl::<u64, 64>(bitmask) }
}
}