lib/x86/crc32: target pclmul,sse4.1 instead of pclmul #397
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In practice, all CPUs that support PCLMULQDQ also support SSE4.1:
Intel: Westmere and later + Silvermont and later
AMD: Bulldozer and later
Therefore, make crc32_x86_pclmulqdq() use SSE4.1 instructions.
To be safe, add an explicit check for SSE4.1 support. Though as per the
above, this is unnecessary in practice (as far as I can tell).
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In practice, all CPUs that support PCLMULQDQ also support SSE4.1:
Therefore, make crc32_x86_pclmulqdq() use SSE4.1 instructions.
To be safe, add an explicit check for SSE4.1 support. Though as per the above, this is unnecessary in practice (as far as I can tell).