43 lines
1.3 KiB
Rust
43 lines
1.3 KiB
Rust
mod sealed {
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pub trait Sealed {}
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}
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use sealed::Sealed;
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/// Specifies the number of lanes in a SIMD vector as a type.
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pub struct LaneCount<const LANES: usize>;
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impl<const LANES: usize> LaneCount<LANES> {
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/// The number of bytes in a bitmask with this many lanes.
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pub const BITMASK_LEN: usize = (LANES + 7) / 8;
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}
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/// Statically guarantees that a lane count is marked as supported.
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///
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/// This trait is *sealed*: the list of implementors below is total.
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/// Users do not have the ability to mark additional `LaneCount<N>` values as supported.
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/// Only SIMD vectors with supported lane counts are constructable.
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pub trait SupportedLaneCount: Sealed {
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#[doc(hidden)]
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type BitMask: Copy + Default + AsRef<[u8]> + AsMut<[u8]>;
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}
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impl<const LANES: usize> Sealed for LaneCount<LANES> {}
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macro_rules! supported_lane_count {
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($($lanes:literal),+) => {
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$(
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impl SupportedLaneCount for LaneCount<$lanes> {
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type BitMask = [u8; ($lanes + 7) / 8];
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}
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)+
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};
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}
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supported_lane_count!(1, 2, 4, 8, 16, 32, 64);
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#[cfg(feature = "all_lane_counts")]
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supported_lane_count!(
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3, 5, 6, 7, 9, 10, 11, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30,
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31, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55,
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56, 57, 58, 59, 60, 61, 62, 63
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);
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