polyval: detect avx+pclmulqdq CPU features on x86#347
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What we actually need support for is using PCLMULQDQ with 128-bit VEX operands. #317 switched to using: target_feature(enable = "avx", enable = "pclmulqdq") ...however `cpufeatures` were being used to detect `vpclmulqdq` which specifically refers to the AVX2 instruction with 256-bit VEX operands, which are only available on CPUs that are many years newer, and which we don't actually use. This switches the `cpufeatures` to detect `avx`+`pclmulqdq` which matches our `target_feature` attributes. Closes #346
This was referenced Jul 11, 2026
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What we actually need support for is using PCLMULQDQ with 128-bit VEX operands. #317 switched to using:
...however
cpufeatureswere being used to detectvpclmulqdqwhich specifically refers to the AVX2 instruction with 256-bit VEX operands, which are only available on CPUs that are many years newer, and which we don't actually use.This switches the
cpufeaturesto detectavx+pclmulqdqwhich matches ourtarget_featureattributes.Closes #346