FNINIT

REG0=XED_REG_X87CONTROL:w:SUPP REG1=XED_REG_X87TAG:w:SUPP REG2=XED_REG_X87STATUS:w:SUPP

x86_64 X86_LEGACY X87_ALU X87 source: xed

XED_FNINIT_X86_LEGACY_ONEBYTE_DB_583945

Encoding

encoding_kindX86_LEGACY
opcode_bytesDB
opcode_mapONEBYTE
mandatory_prefix-
has_modrmTrue
modrm.reg = /4/4
attributesx87_mmx_state_w X87_NOWAIT X87_CONTROL NOTSX
cpl3
raw_encoding0xDB MOD[0b11] MOD=3 REG[0b100] RM[0b011]

Operands (3)

# Role Kind Class / Reg Width Access Visibility Encoded in
0 REG0 REG w W SUPPRESSED MODRM_REG
1 REG1 REG w W SUPPRESSED MODRM_REG
2 REG2 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.