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public text v1 · immutableloop:
movd mm0, [esi]
punpcklbw mm0, mm7
movd mm2, [esi + ebx]
punpcklbw mm2, mm7
paddusw mm4, mm2
psubusw mm4, mm0
movq mm6, mm4
psrlw mm6, mm3
packuswb mm6, mm7
movd [edi], mm6
paddusw mm4, mm2
psubusw mm4, mm0
add edi, eax
add esi, 4
sub ecx, 1
jnz loop