FLDCW

MEM0:r:mem16 REG0=XED_REG_X87CONTROL:w:SUPP REG1=XED_REG_X87STATUS:w:SUPP

x86_64 X86_LEGACY X87_ALU X87 source: xed

XED_FLDCW_X86_LEGACY_ONEBYTE_D9_278318

Encoding

encoding_kindX86_LEGACY
opcode_bytesD9
opcode_mapONEBYTE
mandatory_prefix-
has_modrmTrue
modrm.reg = /5/5
attributesX87_CONTROL NOTSX
cpl3
raw_encoding0xD9 MOD[mm] MOD!=3 REG[0b101] RM[nnn] MODRM()

Operands (3)

# Role Kind Class / Reg Width Access Visibility Encoded in
0 MEM0 MEM R EXPLICIT MODRM_RM
1 REG0 REG w W SUPPRESSED MODRM_REG
2 REG1 REG w W SUPPRESSED MODRM_REG

Micro-ops sequence (0)

No micro-ops authored for this encoding. Emulator semantics not yet defined — decoder still works.