PCMPEQB

MMX PENTIUMMMX x86_64

PCMPEQB is an instruction of the x86_64 architecture (x86 / x86-64 (covers 16/32/64-bit modes)), category MMX. This page lists its 4 encoding forms, distinguished by opcode bytes: 0F, 74.

Each form below links to its full decode: the operand roles and where each one is encoded in the instruction, the flag and register effects, and any micro-op sequence authored for it.

X86_PCMPEQB_X86_LEGACY_0F_74_242698
mm, mm/m64
X86_LEGACY 74 /r MMX
X86_PCMPEQB_X86_LEGACY_0F_74_898451
xmm, xmm/m128
X86_LEGACY 74 /r SSE2
XED_PCMPEQB_X86_LEGACY_0F_74_189841
REG0=MMX_R():rw:q:i8 MEM0:r:q:i8 REG0=MMX_R():rw:q:i8 REG1=MMX_B():r:q:i8
X86_LEGACY 74 0F 74 /r PENTIUMMMX
XED_PCMPEQB_X86_LEGACY_0F_74_864582
REG0=XMM_R():rw:dq:i8 MEM0:r:dq:i8 REG0=XMM_R():rw:dq:i8 REG1=XMM_B():r:dq:i8
X86_LEGACY 74 0F 74 /r SSE2