CMPXCHG_LOCK
MEM0:rcw:b REG0=GPR8_R():r REG1=XED_REG_AL:rcw:SUPP
x86_64 X86_LEGACY SEMAPHORE I486REAL source: xed
XED_CMPXCHG_LOCK_X86_LEGACY_0F_B0_545035
Encoding
| encoding_kind | X86_LEGACY |
| opcode_bytes | B0 |
| opcode_map | 0F |
| mandatory_prefix | - |
| has_modrm | True |
| attributes | BYTEOP LOCKED HLE_ACQ_ABLE HLE_REL_ABLE |
| cpl | 3 |
| raw_encoding | 0x0F 0xB0 MOD[mm] MOD!=3 REG[rrr] RM[nnn] MODRM() lock_prefix |
Operands (3)
| # | Role | Kind | Class / Reg | Width | Access | Visibility | Encoded in |
|---|---|---|---|---|---|---|---|
| 0 | MEM0 | MEM | b | R | EXPLICIT | MODRM_RM | |
| 1 | REG0 | REG | R | EXPLICIT | MODRM_REG | ||
| 2 | REG1 | REG | (=AL) | R | SUPPRESSED | MODRM_REG |
Flag effects (6)
CF = WRITE
PF = WRITE
AF = WRITE
ZF = WRITE
SF = WRITE
OF = WRITE
Micro-ops sequence (0)
No micro-ops authored for this encoding. Emulator semantics not yet defined — decoder still works.