FNSTSW
MEM0:w:mem16 REG0=XED_REG_X87STATUS:rw:SUPP
x86_64 X86_LEGACY X87_ALU X87 source: xed
XED_FNSTSW_X86_LEGACY_ONEBYTE_DD_716326
Encoding
| encoding_kind | X86_LEGACY |
| opcode_bytes | DD |
| opcode_map | ONEBYTE |
| mandatory_prefix | - |
| has_modrm | True |
| modrm.reg = /7 | /7 |
| attributes | X87_NOWAIT X87_CONTROL NOTSX |
| cpl | 3 |
| raw_encoding | 0xDD MOD[mm] MOD!=3 REG[0b111] RM[nnn] MODRM() |
Operands (2)
| # | Role | Kind | Class / Reg | Width | Access | Visibility | Encoded in |
|---|---|---|---|---|---|---|---|
| 0 | MEM0 | MEM | w | W | EXPLICIT | MODRM_RM | |
| 1 | REG0 | REG | RW | SUPPRESSED | MODRM_REG |
Micro-ops sequence (0)
No micro-ops authored for this encoding. Emulator semantics not yet defined — decoder still works.