Simplify SVE table lookup #494
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solidpixel
commented
Aug 10, 2024
solidpixel
commented
Aug 10, 2024
bengaineyarm
previously approved these changes
Aug 15, 2024
bengaineyarm
approved these changes
Aug 15, 2024
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The design of the SVE vtbl allows us to simply bitwise OR successive lookups for a multi-lookup table because, unlike x86 shuffles, it's guaranteed that high values outside of the active 32-bit slice return zero.
This has no impact on compression, but gives a small (0.5%) improvement to decompression performance.