This page is under construction. Even if I do get around to finishing it, Christian Ludloff's opcode maps will likely be better. Mine are simpler, though.
The IA-32 opcode is necessarily complex, and it's best broken up into many tables. I have finished most of them. Do the floating point table for me and you may get extra credit.
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | A | B | C | D | E | F | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 0 | ADD Eb,Gb |
ADD Ev,Gv |
ADD Gb,Eb |
ADD Gv,Ev |
ADD AL,Ib |
ADD eAX,Iv |
PUSH ES |
POP ES |
OR Eb,Gb |
OR Ev,Gv |
OR Gb,Eb |
OR Gv,Ev |
OR AL,Ib |
OR eAX,Iv |
PUSH CS |
two byte opcodes |
| 1 | ADC Eb,Gb |
ADC Ev,Gv |
ADC Gb,Eb |
ADC Gv,Ev |
ADC AL,Ib |
ADC eAX,Iv |
PUSH SS |
POP SS |
SBB Eb,Gb |
SBB Ev,Gv |
SBB Gb,Eb |
SBB Gv,Ev |
SBB AL,Ib |
SBB eAX,Iv |
PUSH DS |
POP DS |
| 2 | AND Eb,Gb |
AND Ev,Gv |
AND Gb,Eb |
AND Gv,Ev |
AND AL,Ib |
AND eAx,Iv |
ES: | DAA | SUB Eb,Gb |
SUB Ev,Gv |
SUB Gb,Eb |
SUB Gv,Ev |
SUB AL,Ib |
SUB eAX,Iv |
CS:/ Hint not taken: |
DAS |
| 3 | XOR Eb,Gb |
XOR Ev,Gv |
XOR Gb,Eb |
XOR Gv,Ev |
XOR AL,Ib |
XOR eAX,Iv |
SS: | AAA | CMP Eb,Gb |
CMP Ev,Gv |
CMP Gb,Eb |
CMP Gv,Ev |
CMP AL,Ib |
CMP eAX,Iv |
DS:/ Hint taken: |
AAS |
| 4 | INC eAX |
INC eCX |
INC eDX |
INC eBX |
INC eSP |
INC eBP |
INC eSI |
INC eDI |
DEC eAX |
DEC eCX |
DEC eDX |
DEC eBX |
DEC eSP |
DEC eBP |
DEC eSI |
DEC eDI |
| 5 | PUSH eAX |
PUSH eCX |
PUSH eDX |
PUSH eBX |
PUSH eSP |
PUSH eBP |
PUSH eSI |
PUSH eDI |
POP eAX |
POP eCX |
POP eDX |
POP eBX |
POP eSP |
POP eBP |
POP eSI |
POP eDI |
| 6 | PUSHA/ PUSHAD |
POPA/ POPAD |
BOUND Gv,Ma |
ARPL Ew,Rw |
FS: | GS: | OPSIZE: | ADSIZE: | PUSH Iv |
IMUL Gv,Ev,Iv |
PUSH Ib |
IMUL Gv,Ev,Ib |
INSB Yb,DX |
INSW/ INSD Yv,DX |
OUTSB DX,Xb |
OUTSW/ OUTSD DX,Xv |
| 7 | JO Jb |
JNO Jb |
JB/JC/ JNAE Jb |
JNB/JNC/ JAE Jb |
JZ/ JE Jb |
JNZ/ JNE Jb |
JBE/ JNA Jb |
JNBE/ JA Jb |
JS Jb |
JNS Jb |
JP/ JPE Jb |
JNP/ JPO Jb |
JL/ JNGE Jb |
JNL/ JGE Jb |
JLE/ JNG Jb |
JNLE/ JG Jb |
| 8 | group #1 Eb,Ib |
group #1 Ev,Iv |
group #1 Eb,Ib |
group #1 Ev,Ib |
TEST Eb,Gb |
TEST Ev,Gv |
XCHG Eb,Gb |
XCHG Ev,Gv |
MOV Eb,Gb |
MOV Ev,Gv |
MOV Gb,Eb |
MOV Gv,Ev |
MOV Ew,Sw |
LEA Gv,M |
MOV Sw,Ew |
group #10 |
| 9 | NOP/ (F3) PAUSE |
XCHG eCX,eAX |
XCHG eDX,eAX |
XCHG eBX,eAX |
XCHG eSP,eAX |
XCHG eBP,eAX |
XCHG eSI,eAX |
XCHG eDI,eAX |
CBW/ CWDE |
CWD/ CDQ |
CALL Ap |
WAIT/ FWAIT |
PUSHF Fv |
POPF Fv |
SAHF | LAHF |
| A | MOV AL,Ob |
MOV eAX,Ov |
MOV Ob,AL |
MOV Ov,eAX |
MOVSB Xb,Yb |
MOVSW/ MOVSD Xv,Yv |
CMPSB Xb,Yb |
CMPSW/ CMPSD Xv,Yv |
TEST AL,Ib |
TEST eAX,Iv |
STOSB Yb,AL |
STOSW/ STOSD Yv,eAX |
LODSB AL,Xb |
LODSW/ LODSD eAX,Xv |
SCASB AL,Yb |
SCASW/ SCASD eAX,Yv |
| B | MOV AL,Ib |
MOV CL,Ib |
MOV DL,Ib |
MOV BL,Ib |
MOV AH,Ib |
MOV CH,Ib |
MOV DH,Ib |
MOV BH,Ib |
MOV eAX,Iv |
MOV eCX,Iv |
MOV eDX,Iv |
MOV eBX,Iv |
MOV eSP,Iv |
MOV eBP,Iv |
MOV eSI,Iv |
MOV eDI,Iv |
| C | group #2 Eb,Ib |
group #2 Ev,Ib |
RET near Iw |
RET near | LES Gv,Mp |
LDS Gv,Mp |
group #12 Eb,Ib |
group #12 Ev,Iv |
ENTER Iw,Ib |
LEAVE | RET far Iw |
RET far | INT 3 | INT Ib |
INTO | IRET |
| D | group #2 Eb,1 |
group #2 Ev,1 |
group #2 Eb,CL |
group #2 Ev,CL |
AAM Ib |
AAD Ib |
XLAT | floating point instructions | ||||||||
| E | LOOPNE/ LOOPNZ Jb |
LOOPE/ LOOPZ Jb |
LOOP Jb |
JCXZ/ JECXZ Jb |
IN AL,Ib |
IN eAX,Ib |
OUT Ib,AL |
OUT Ib,eAX |
CALL Jv |
JMP Jv |
JMP Ap |
JMP Jb |
IN AL,DX |
IN eAX,DX |
OUT DX,AL |
OUT DX,eAX |
| F | LOCK: | REPNE: | REP:/ REPE: |
HLT | CMC | group #3 Eb |
group #3 Ev |
CLC | STC | CLI | STI | CLD | STD | group #4 | group #5 | |
| 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | ||
|---|---|---|---|---|---|---|---|---|---|
| n/a | 0 | group #6 | group #7 | LAR Gv,Ew |
LSL Gv,Ew |
CLTS | |||
| n/a | 1 | MOVUPS Vo,Wo (66) MOVUPD Vo,Wo (F3) MOVSS Vd,Wd (F2) MOVSD Vq,Wq |
MOVUPS Wo,Vo (66) MOVUPD Wo,Vo (F3) MOVSS Wd,Vd (F2) MOVSD Wq,Vq |
MOVLPS Vq,Mq MOVHLPS Vq,Vq (66) MOVLPD Vq,Mq |
MOVLPS Mq,Vq (66) MOVLPD Mq,Vq |
UNPCKLPS Vo,Wq (66) UNPCKLPD Vo,Wq |
UNPCKHPS Vo,Wo (66) UNPCKHPD Vo,Wo |
MOVHPS Vq,Mq MOVLHPS Vq,Vq (66) MOVHPD Vq,Mq |
MOVHPS Mq,Vq (66) MOVHPD Mq,Vq |
| n/a | 2 | MOV Rd,Cd |
MOV Rd,Dd |
MOV Cd,Rd |
MOV Dd,Rd |
MOV Rd,Td |
MOV Td,Rd |
||
| n/a | 3 | WRMSR | RDTSC | RDMSR | RDPMC | SYSENTER | SYSEXIT | ||
| n/a | 4 | CMOVO Gv,Ev |
CMOVNO Gv,Ev |
CMOVB/ CMOVNAE Gv,Ev |
CMOVNB/ CMOVAE Gv,Ev |
CMOVZ/ CMOVE Gv,Ev |
CMOVNZ/ CMOVNE Gv,Ev |
CMOVBE/ CMOVNA Gv,Ev |
CMOVNBE/ CMOVA Gv,Ev |
| n/a | 5 | MOVMSKPS Gd,Vo |
SQRTPS Vo,Wo |
RSQRTPS Vo,Wo |
RCPPS Vo,Wo |
ANDPS Vo,Wo |
ANDNPS Vo,Wo |
ORPS Vo,Wo |
XORPS Vo,Wo |
| F3 | SQRTSS Vd,Wd |
RSQRTSS Vd,Wd |
RCPSS Vd,Wd |
||||||
| 66 | MOVMSKPD Gd,Vo |
SQRTPD Vo,Wo |
ANDPD Vo,Wo |
ANDNPD Vo,Wo |
ORPD Vo,Wo |
XORPD Vo,Wo |
|||
| F2 | SQRTSD Vq,Wq |
||||||||
| n/a | 6 | PUNPCKL- BW Pq,Qd |
PUNPCKL- WD Pq,Qd |
PUNPCKL- DQ Pq,Qd |
PACKSSWB Pq,Qq |
PCMPGTB Pq,Qq |
PCMPGTW Pq,Qq |
PCMPGTD Pq,Qq |
PACKUSWB Pq,Qq |
| 66 | PUNPCKL- BW Vo,Wq |
PUNPCKL- WD Vo,Wq |
PUNPCKL- DQ Vo,Wq |
PACKSSWB Vo,Wo |
PCMPGTB Vo,Wo |
PCMPGTW Vo,Wo |
PCMPGTD Vo,Wo |
PACKUSWB Vo,Wo |
|
| n/a | 7 | PSHUFW Pq,Qq,Ib |
group #13 PSHIMW |
group #14 PSHIMD |
group #15 PSHIMQ |
PCMPEQB Pq,Qq |
PCMPEQW Pq,Qq |
PCMPEQD Pq,Qq |
EMMS |
| F3 | PSHUFHW Vo,Wo,Ib |
||||||||
| 66 | PSHUFD Vo,Wo,Ib |
group #13 PSHIMW |
group #14 PSHIMD |
group #15 PSHIMQ/DQ |
PCMPEQB Vo,Wo |
PCMPEQW Vo,Wo |
PCMPEQD Vo,Wo |
||
| F2 | PSHUFLW Vo,Wo,Ib |
||||||||
| n/a | 8 | JO Jv |
JNO Jv |
JB Jv |
JNB Jv |
JZ Jv |
JNZ Jv |
JBE Jv |
JNBE Jv |
| n/a | 9 | SETO Eb |
SETNO Eb |
SETB Eb |
SETNB Eb |
SETZ Eb |
SETNZ Eb |
SETBE Eb |
SETNBE Eb |
| n/a | A | PUSH FS |
POP FS |
CPUID | BT Ev,Gv |
SHLD Ev,Gv,Ib |
SHLD Ev,Gv,CL |
||
| n/a | B | CMPXCHG Eb,Gb |
CMPXCHG Ev,Gv |
LSS Gv,Mp |
BTR Ev,Gv |
LFS Gv,Mp |
LGS Gv,Mp |
MOVZX Gv,Eb |
MOVZX Gv,Ew |
| n/a | C | XADD Eb,Gb |
XADD Ev,Gv |
CMPccPS #2 Vo,Wo,Ib |
MOVNTI Md,Gd (SSE2-MEM) |
PINSRW Pq,Mw,Ib Pq,G[wd],Ib |
PEXTRW Gd,Pq,Ib |
SHUFPS Vo,Wo,Ib |
group #9 |
| F3 | CMPccSS #2 Vd,Wd,Ib |
||||||||
| 66 | CMPccPD #2 Vo,Wo,Ib |
PINSRW Vo,Mw,Ib Vo,G[wd],Ib |
PEXTRW Gd,Vo,Ib |
SHUFPD Vo,Wo,Ib |
|||||
| F2 | CMPccSD #2 Vq,Wq,Ib |
||||||||
| n/a | D | PSRLW Pq,Qq |
PSRLD Pq,Qq |
PSRLQ Pq,Qq |
PADDQ Pq,Qq (MMX-SSE2) |
PMULLW Pq,Qq |
PMOVMSKB Gd,Pq |
||
| F3 | MOVQ2DQ Vo,Pq |
||||||||
| 66 | PSRLW Vo,Wo (!) |
PSRLD Vo,Wo (!) |
PSRLQ Vo,Wo (!) |
PADDQ Vo,Wo |
PMULLW Vo,Wo |
MOVQ Mq,Vq Vq,Vq |
PMOVMSKB Gd,Vo |
||
| F2 | MOVDQ2Q Pq,Vq |
||||||||
| n/a | E | PAVGB Pq,Qq |
PSRAW Pq,Qq |
PSRAD Pq,Qq |
PAVGW Pq,Qq |
PMULHUW Pq,Qq |
PMULHW Pq,Qq |
MOVNTQ Mq,Pq |
|
| F3 | CVTDQ2PD Vo,Wq |
||||||||
| 66 | PAVGB Vo,Wo |
PSRAW Vo,Wo (!) |
PSRAD Vo,Wo (!) |
PAVGW Vo,Wo |
PMULHUW Vo,Wo |
PMULHW Vo,Wo |
CVTTPD2DQ Vo,Wo |
MOVNTDQ Mo,Vo |
|
| F2 | CVTPD2DQ Vo,Wo |
||||||||
| n/a | F | PSLLW Pq,Qq |
PSLLD Pq,Qq |
PSLLQ Pq,Qq |
PMULUDQ Pq,Qq (MMX-SSE2) |
PMADDWD Pq,Qq |
PSADBW Pq,Qq |
MASKMOVQ Pq,Pq |
|
| 66 | PSLLW Vo,Wo (!) |
PSLLD Vo,Wo (!) |
PSLLQ Vo,Wo (!) |
PMULUDQ Vo,Wo |
PMADDWD Vo,Wo |
PSADBW Vo,Wo |
MASKMOV- DQU Vo,Vo |
| 8 | 9 | A | B | C | D | E | F | ||
|---|---|---|---|---|---|---|---|---|---|
| n/a | 0 | INVD | WBINVD | UD2 | |||||
| n/a | 1 | group #17 | (hinting NOP) | (hinting NOP) | (hinting NOP) | (hinting NOP) | (hinting NOP) | (hinting NOP) | (hinting NOP) |
| n/a | 2 | MOVAPS Vo,Wo |
MOVAPS Wo,Vo |
CVTPI2PS Vq,Qq |
MOVNTPS Mo,Vo |
CVTTPS2PI Pq,Wq |
CVTPS2PI Pq,Wq |
UCOMISS Vd,Wd |
COMISS Vd,Wd |
| F3 | CVTSI2SS Vd,Ed |
CVTTSS2SI Gd,Wd |
CVTSS2SI Gd,Wd |
||||||
| 66 | MOVAPD Vo,Wo |
MOVAPD Wo,Vo |
CVTPI2PD Vo,Qq |
MOVNTPD Mo,Vo |
CVTTPD2PI Pq,Wo |
CVTPD2PI Pq,Wo |
UCOMISD Vq,Wq |
COMISD Vq,Wq |
|
| F2 | CVTSI2SD Vq,Ed |
CVTTSD2SI Gd,Wq |
CVTSD2SI Gd,Wq |
||||||
| n/a | 3 | ||||||||
| n/a | 4 | CMOVS Gv,Ev |
CMOVNS Gv,Ev |
CMOVP Gv,Ev |
CMOVNP Gv,Ev |
CMOVL Gv,Ev |
CMOVNL Gv,Ev |
CMOVLE Gv,Ev |
CMOVNLE Gv,Ev |
| n/a | 5 | ADDPS Vo,Wo |
MULPS Vo,Wo |
CVTPS2PD Vo,Wq |
CVTDQ2PS Vo,Wo |
SUBPS Vo,Wo |
MINPS Vo,Wo |
DIVPS Vo,Wo |
MAXPS Vo,Wo |
| F3 | ADDSS Vd,Wd |
MULSS Vd,Wd |
CVTSS2SD Vq,Wd |
CVTTPS2DQ Vo,Wo |
SUBSS Vd,Wd |
MINSS Vd,Wd |
DIVSS Vd,Wd |
MAXSS Vd,Wd |
|
| 66 | ADDPD Vo,Wo |
MULPD Vo,Wo |
CVTPD2PS Vo,Wo |
CVTPS2DQ Vo,Wo |
SUBPD Vo,Wo |
MINPD Vo,Wo |
DIVPD Vo,Wo |
MAXPD Vo,Wo |
|
| F2 | ADDSD Vq,Wq |
MULSD Vq,Wq |
CVTSD2SS Vd,Wq |
SUBSD Vq,Wq |
MINSD Vq,Wq |
DIVSD Vq,Wq |
MAXSD Vq,Wq |
||
| n/a | 6 | PUNPCKH- BW Pq,Qq |
PUNPCKH- WD Pq,Qq |
PUNPCKH- DQ Pq,Qq |
PACKSSDW Pq,Qq |
MOVD Pq,Ed |
MOVQ Pq,Qq |
||
| F3 | MOVDQU Vo,Wo |
||||||||
| 66 | PUNPCKH- BW Vo,Wo |
PUNPCKH- WD Vo,Wo |
PUNPCKH- DQ Vo,Wo |
PACKSSDW Vo,Wo |
PUNPCKL- QDQ Vo,Wq |
PUNPCKH- QDQ Vo,Wo |
MOVD Vo,Ed |
MOVDQA Vo,Wo |
|
| n/a | 7 | MOVD Ed,Pd |
MOVQ Qq,Pq |
||||||
| F3 | MOVQ Vo,Mq Vq,Vq |
MOVDQU Wo,Vo |
|||||||
| 66 | MOVD Ed,Vd |
MOVDQA Wo,Vo |
|||||||
| n/a | 8 | JS Jv |
JNS Jv |
JP Jv |
JNP Jv |
JL Jv |
JNL Jv |
JLE Jv |
JNLE Jv |
| n/a | 9 | SETS Eb |
SETNS Eb |
SETP Eb |
SETNP Eb |
SETL Eb |
SETNL Eb |
SETLE Eb |
SETNLE Eb |
| n/a | A | PUSH GS |
POP GS |
RSM | BTS Ev,Gv |
SHRD Ev,Gv,Ib |
SHRD Ev,Gv,CL |
group #16 | IMUL Gv,Ev |
| n/a | B | group #11 | group #8 Ev,Ib |
BTC Ev,Gv |
BSF Gv,Ev |
BSR Gv,Ev |
MOVSX Gv,Eb |
MOVSX Gv,Ew |
|
| n/a | C | BSWAP EAX |
BSWAP ECX |
BSWAP EDX |
BSWAP EBX |
BSWAP ESP |
BSWAP EBP |
BSWAP ESI |
BSWAP EDI |
| n/a | D | PSUBUSB Pq,Qq/ (66) Vo,Wo |
PSUBUSW Pq,Qq/ (66) Vo,Wo |
PMINUB Pq,Qq/ (66) Vo,Wo |
PAND Pq,Qq/ (66) Vo,Wo |
PADDUSB Pq,Qq/ (66) Vo,Wo |
PADDUSW Pq,Qq/ (66) Vo,Wo |
PMAXUB Pq,Qq/ (66) Vo,Wo |
PANDN Pq,Qq/ (66) Vo,Wo |
| n/a | E | PSUBSB Pq,Qq/ (66) Vo,Wo |
PSUBSW Pq,Qq/ (66) Vo,Wo |
PMINSW Pq,Qq/ (66) Vo,Wo |
POR Pq,Qq/ (66) Vo,Wo |
PADDSB Pq,Qq/ (66) Vo,Wo |
PADDSW Pq,Qq/ (66) Vo,Wo |
PMAXSW Pq,Qq/ (66) Vo,Wo |
PXOR Pq,Qq/ (66) Vo,Wo |
| n/a | F | PSUBB Pq,Qq/ (66) Vo,Wo |
PSUBW Pq,Qq/ (66) Vo,Wo |
PSUBD Pq,Qq/ (66) Vo,Wo |
PSUBQ Pq,Qq/ (66) Vo,Wo |
PADDB Pq,Qq/ (66) Vo,Wo |
PADDW Pq,Qq/ (66) Vo,Wo |
PADDD Pq,Qq/ (66) Vo,Wo |
Not finished
| |
spare=000 | spare=001 | spare=010 | spare=011 | spare=100 | spare=101 | spare=110 | spare=111 |
|---|---|---|---|---|---|---|---|---|
| group #1 (80..83) |
ADD | OR | ADC | SBB | AND | SUB | XOR | CMP |
| group #2 (C0..C1) (D0..D3) |
ROL | ROR | RCL | RCR | SHL | SHR | SAR | |
| group #3 (F6..F7) |
TEST Ib/Iv |
NOT | NEG | MUL AL/eAX |
IMUL AL/eAX |
DIV AL/eAX |
IDIV AL/eAX |
|
| group #4 (FE) |
INC Eb |
DEC Eb |
||||||
| group #5 (FF) |
INC Ev |
DEC Ev |
CALL Ev |
CALL Mp |
JMP Ev |
JMP Mp |
PUSH Ev |
|
| group #6 (0F00) |
SLDT Ew |
STR Ew |
LLDT Ew |
LTR Ew |
VERR Ew |
VERW Ew |
||
| group #7 (0F01) |
SGDT Ms |
SIDT Ms |
LGDT Ms |
LIDT Ms |
SMSW Ew |
LMSW Ew |
INVLPG Mb |
|
| group #8 (0FBA) |
BT | BTS | BTR | BTC | ||||
| group #9 (0FC7) |
CMPXCHG Mq |
|||||||
| group #10 (8F) |
POP Ev |
|||||||
| group #11 (0FB9) |
UD2 | UD2 | UD2 | UD2 | UD2 | UD2 | UD2 | UD2 |
| group #12 (C6..C7) |
MOV | |||||||
| group #13 (0F71) |
PSRLW Pq,Ib/ (66) PSRLW Vo,Ib |
PSRAW Pq,Ib/ (66) PSRAW Vo,Ib |
PSLLW Pq,Ib/ (66) PSLLW Vo,Ib |
|||||
| group #14 (0F72) |
PSRLD Pq,Ib/ (66) PSRLD Vo,Ib |
PSRAD Pq,Ib/ (66) PSRAD Vo,Ib |
PSLLD Pq,Ib/ (66) PSLLD Vo,Ib |
|||||
| group #15 (0F73) |
PSRLQ Pq,Ib/ (66) PSRLQ Vo,Ib |
(66) PSRLDQ Vo,Ib |
PSLLQ Pq,Ib/ (66) PSLLQ Vo,Ib |
(66) PSLLDQ Vo,Ib |
||||
| group #16 (0FAE) |
FXSAVE M512 |
FXRSTOR M512 |
LDMXCSR Md |
STMXCSR Md |
LFENCE | MFENCE | CLFLUSH M/ SFENCE |
|
| group #17 (0F18) |
PREFETCHNTA M |
PREFETCHT0 M |
PREFETCHT1 M |
PREFETCHT2 M |
| Operand Addressing Method Codes | |
|---|---|
| A | direct address; no mod R/M byte; address of operand is encoded in instruction; no base register, index register, or scaling factor can be applied; example: JMP (EA) |
| C | reg field of mod R/M byte selects a control register |
| D | reg field of mod R/M byte selects a debug register |
| E | mod R/M byte follows opcode and specifies operand; operand is either a general register or a memory address |
| F | flags register |
| G | reg field of mod R/M byte selects a general register |
| I | immediate data; value of operand is encoded in subsequent bytes of instruction |
| J | instruction contains a relative offset to be added to the instruction pointer register |
| M | mod R/M byte may refer only to memory |
| O | no mod R/M byte; offset of operand is coded as a word or double word (depending on address size attribute) in instruction; no base register, index register, or scaling factor can be applied; example: MOV (A0..A3) |
| P | reg field of mod R/M byte selects a 64-bit MMX register |
| Q | mod R/M byte follows opcode and specifies operand; operand is either an MMX register or a memory address |
| R | mod field of mod R/M byte may refer only to a general register |
| S | reg field of mod R/M byte selects a segment register |
| T | reg field of mod R/M byte selects a test register |
| V | reg field of mod R/M byte selects a 128-bit XMM register |
| W | mod R/M byte follows opcode and specifies operand; operand is either an XMM register or a memory address |
| X | memory addressed by DS:eSI register pair; eg. MOVS, CMPS, OUTS, LODS |
| Y | memory addressed by ES:eDI register pair; eg. MOVS, CMPS, INS, STOS, SCAS |
| Operand Type Codes | |
|---|---|
| b | byte (regardless of operand size attribute) |
| w | word (regardless of operand size attribute) |
| d | dword (regardless of operand size attribute) |
| q | qword (regardless of operand size attribute) |
| o | oword (regardless of operand size attribute) |
| c | byte or word, depending on operand size attribute |
| v | word or doubleword, depending on operand size attribute |
| a | two word or two doubleword operands in memory, depending on operand size attribute (used only by BOUND) |
| p | 32-bit or 48-bit pointer, depending on operand size attribute |
| s | six-byte pseudo-descriptor |