Fix SHA-256 SHA-NI AV on unaligned K256 constants (closes #75)#76
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The SHA-NI SHA-256 compress routine added the round constants with a legacy-SSE `paddd xmm0, [r9 + offset]` memory operand. Such operands require 16-byte alignment, but K256 is a plain global const with no alignment guarantee, so a non-aligned layout triggered a #GP / access violation (0xC0000005) on x86-64. Load each constant quad with `movdqu` first and add register-to-register (`paddd` is commutative, so the result is unchanged). This drops the alignment requirement entirely, matching the SSE2/SSSE3/AVX2 backends, and leaves the xmm7 palignr scratch untouched.
beytullahakyuz
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beytullahakyuz
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I tested it on a Windows x64 system. The bug has been fixed. Thank you.
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The SHA-NI SHA-256 compress routine added the round constants with a legacy-SSE
paddd xmm0, [r9 + offset]memory operand. Such operands require 16-byte alignment, but K256 is a plain global const with no alignment guarantee, so a non-aligned layout triggered a #GP / access violation (0xC0000005) on x86-64.Load each constant quad with
movdqufirst and add register-to-register (padddis commutative, so the result is unchanged). This drops the alignment requirement entirely, matching the SSE2/SSSE3/AVX2 backends, and leaves the xmm7 palignr scratch untouched.