fix: remove AVX dependency from SSE x1 implementation#64
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The Win64 epilog in sha256_sse_x1.S used vmovdqa (AVX) to restore callee-saved XMM registers while the prolog used movdqa (SSE). This would fault on CPUs with SSE but no AVX. Replace with movdqa to match. Also fix the CPU detection in hashtree.c where the SSE fallback had a duplicate bit_AVX check (dead code), replacing it with bit_SSSE3 which is what the SSE x1 implementation actually requires (pshufb, palignr). Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
james-prysm
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james-prysm
previously approved these changes
Mar 26, 2026
james-prysm
approved these changes
Mar 26, 2026
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Summary
vmovdqa(AVX) withmovdqa(SSE) in the XMM register restore ofsha256_sse_x1.S. The prolog already usedmovdqa; the epilog was inconsistent and would fault on CPUs with SSSE3 but no AVX.hashtree.chad a duplicatebit_AVXcheck, making it dead code. Changed tobit_SSSE3, which is the actual minimum requirement for the SSE x1 implementation (pshufb,palignr).🤖 Generated with Claude Code