FST
X87_ALU X87 x86_64
FST is an instruction of the x86_64 architecture (x86 / x86-64 (covers 16/32/64-bit modes)), category X87_ALU. This page lists its 4 encoding forms, distinguished by opcode bytes: D9, DD.
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_FST_X86_LEGACY_ONEBYTE_DD_10310
st(i)
XED_FST_X86_LEGACY_ONEBYTE_D9_689732
MEM0:w:mem32real REG0=XED_REG_ST0:r:IMPL:f80 REG1=XED_REG_X87STATUS:w:SUPP
XED_FST_X86_LEGACY_ONEBYTE_DD_155858
REG0=X87():w:f80 REG1=XED_REG_ST0:r:IMPL:f80 REG2=XED_REG_X87STATUS:w:SUPP
XED_FST_X86_LEGACY_ONEBYTE_DD_674784
MEM0:w:m64real REG0=XED_REG_ST0:r:IMPL:f80 REG1=XED_REG_X87STATUS:w:SUPP