x86 Instruction Set

UMBC CMSC 211

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Instruction	Format	Description	O	D	I	S	Z	A	P	C
AAA	AAA	Adjust alter addition	?			?	?	*	P	*
AAD	AAD	ASCII adjust before division	?			*	*	?	*	?
AAM	AAM	ASCII adjust after multiply	?			*	*	?	*	?
AAS	AAS	ASCII adjust after subtraction	?			?	?	*	?	*
ADC	ADC reg, reg ADC mem, reg ADC reg, mem ADC reg, immed ADC accum, immed	Add with carry	*			*	*	*	*	*
ADD	ADC reg, reg ADC mem, reg ADC reg, mem ADC reg, immed ADC accum, immed	Add	*			*	*	*	*	*
AND	ADC reg, reg ADC mem, reg ADC reg, mem ADC mem, reg ADC reg, mem ADC reg, immed ADC accum, immed	Logical AND	*			*	*	?	*	0
CALL	CALL nearlabel CALL farlabel CALL reg CALL mem16 CALL mem32	Call a procedure
CBW	Convert byte to word
CLC	CLC	Clear carry flag								0
CLD	CLD	Clear direction flag		0
CLI	CLI	Clear interrupt flag			0
CMC	CMC	Complement carry flag								*
CMP	CMP	C
CMP	CMP reg, reg CMP mem, reg CMP reg, mem CMP reg, immed CMP mem, immed CMP accum, immed	Compare	*			*	*	*	*	*	*
CMPS	CMPS source, dest CMPS segreg:source, ES:dest	Compare strings	*			*	*	*	*	*
CMPSB	CMPSB	Compare strings	*			*	*	*	*	*
*
CMPSW	CMPSW	Compare strings	*			*	*	*	*	*
CWD	CWD	Convert word to doubleword
DAA	DAA	Decimal after addition		?			*	*	*	*	*
DAS	DAS	Decimal adjust after subtraction	?			*	*	*	*	*
DEC	Decrement		*			*	*	*	*	*
DIV	DIV reg DIV mem	Unsigned integer divide	?			?	?	?	?	?
ESC	ESC immed, reg ESC immed, mem	Escape
HLT	HLT	Halt
IDIV	IDIV reg IDIV mem	TD WIDTH="32%" VALIGN="TOP"> Signed integer division	?			?	?	?	?	?
IMUL	IMUL reg IMUL mem	Signed integer multiply	*			?	?	?	?	*
IN	IN accum, immed IN accum, DX	Input from port
INC	INC reg INC mem	Increment	*			*	*	*	*
INT	INT immed INT 3	Interrupt			O			">
INTO	INTO	Interrupt on overflow			*	*
IRET	IRET	Interrupt return	*	*	*	*	*	*	*	*
<	JA	JA shortlabel	Jump if above
JAE	JAE shortlabel	Jump if above or equal
JB	JB shortlabel	Jump if below
JBE	JBE shortlabel	Jump if below or equal
JC	JC shortlabel	Jump if carry
JE	JAE shortlabel	Jump if equal
JG	JG shortlabel	Jump if greater

JGE	JGE shortlabel	Jump if greater or equal
JL	JL shortlabel	Jump if less
JLE	JLE shortlabel	Jump if less or equal
JNA	JNA shortlabel	Jump if not above
JNAE	JNAE shortlabel	Jump if not above or equal
JNB	JNB shorVALIGN="TOP"> JNB shortlabel	Jump if not below
JNBE	JNBE shortlabel	Jump if not below or equal
JNC	JNC shortlabel	Jump if not carry
JNE	JNE shortlabel	Jump if not equal
JNG	JNG shortlabel	Jump if not greater
JNGE	JNGE shortlabel	Jump if not greater or equal Jump if not greater or equal
JNL	JNL shortlabel	Jump if not less
JNLTOP"> JNLE	JNLE shortlabel	Jump if not less or equal
JNO	JNO shortlabel	Jump if not overflow
JNP	JNP shortlabel	Jump if not parity				&nbs/TD>
JNS	JNS shortlabel	Jump if not sign
JNZ	JNZ shortlabel	Jump if not zero
JO	JO shortlabel		Jump if overflow
JP	JP shortlabel	Jump if parity
JPE	JPE shortlabel	Jump if parity even							TD>
JPO	JPO shortlabel	Jump if parity odd
JS	JS shortlabel	Jump if sign
JZ	JZ shortlabel	Jump if zero		&nbp;
JCXZ	JCXZ shortlabel	Jump if CX is zero
JMP	JMP shortlabel JMP nearlabel JMP farlabel JMP reg16 JMP mem16 JMP mem32	Jump unconditionally to label
LAHF	LAHF	Load flags into AH
LDS	LDS reg, mem32	Load register and DS
LEA	LEA reg, mem	Load effective address
LES	LES reg, mem32	Load register and ES
LOCK	LOCK instruction LOCK instruction	Lock the system bus
LODS	LODS mem LODS segreg:mem	Load string
LODSB	LODSB	Load string
LODSW	LODSW	Load string
LOOP	LOOP shortlabel	Loop
LOOPE	LOOPE shortlabel	Loop if equal
LOOPZ	LOOPZ shortlabel	Loop if zero
LOOPNE	LOOPNE shortlabel	Loop if not equal
LOOPNZ	LOOPNZ shortlabel	Loop if not zero
MOV	MOV reg, reg MOV mem, reg MOV reg, mem MOV reg16, segreg MOV segreg, reg16	Copies a byte or word
MOVS	MOVS dest, source MOVS ES:dest, segreg:source	Move string
MOVSB	MOVSB	Move string
MOVSW	WIDTH="30%" VALIGN="TOP"> MOVSW	Move string
MUL	MUL reg MUL mem	Unsigned integer multiply	*			?	?	?	?	*
NEG	NEG reg NEG mem	Negate	*	&nbFONT>			*	*	*	*	*
NOP	NOP	No operation
NOT	NOT reg NOT mem	Logical NOT								;
OR	OR reg, reg OR mem, reg OR reg, mem OR reg, immed OR mem, immed OR accum, immed	Logical OR	0			*	*	?	*	0
OUT	OUT immed8, accum OUT DX, accum	Output to port
POP	POP	POP reg16 POP mem16 POP segreg	Pop from stack
PUSH	PUSH reg16 PUSH mem16 PUSH segreg	Push on stack
PUSHF	PUSHF	Push flags
RCL	RCL reg, 1 RCL reg, CL RCL mem, 1 RCL mem, CL	Rotate carry left	*							*
RCR	RCR reg, 1 RCR reg, CL RCR mem, 1 RCR mem, CL	Rotate carry right	*							">	*
REP	REP MOVS dest, source	Repeat string
REPZ	REPZ SCAS dest REPZ SCASB	Conditional repeat string					*
REPE	REPE SCASW	Conditional repeat string					*
REPNZ	REPNZ SCAS dest REPNZ SCASW	Conditional repeat string					*

REPNE	REPNE SCASB	Conditional repeat string					*
RET	RET RET immed8	Return from procedure
RETN	RETN RETN immed8	Return from near procedure
RETF	RETF RETF immed8	Return from far procedure
ROL	ROL reg, 1 ROL reg, CL ROL mem, 1 ROL mem, CL	Rotate right	*								*
ROR	ROR reg, 1 ROR reg, CL ROR mem, 1 ROR mem, CL	Rotate right	*							*
SAHF	SAHF	Store AH into flags				*	*	*	*	*
SAL		SAL reg, 1 SAL reg, CL SAL mem, 1 SAL mem, CL	Shift arithmetic left	*			*	*	?	*	*
SAR	SAR reg, 1 SAR reg, CL SAR mem, 1 SAR mem, CL	Shift arithmetic right	*			*	*	?	*	*
SBB	SBB	SBB reg, reg SBB mem, reg SBB reg, mem SBB reg, immed SBB mem, immed SBB accum, immed	Subtract with borrow	*			*	*	*	*	*
SCAS	SCAS dest SCAS ES:dest	Scan string		*			*	*	*	*	*
SCASB	SCASB	Scan string	*			*	*	*	*	*
SCASW	SCASW	Scan string	*				*	*	*	*	*
SHL	SHL reg, 1 SHL reg, CL SHL mem, 1 SHL mem, CL	Shift left	*			*	*	?	*	*
SHR	SHR reg, 1 SHR reg, CL SHR mem, 1 SHR mem, CL	Shift right	*				*	*	?	*	*
STC	STC	Set carry flag								1
STD	STD	Set direction flag		1
STI	STI	Set interrupt flag			1
STOS	STOS mem STOS ES:mem	Store string
STOSB	STOSW	Store string			&bsp;
STOSB	STOSW	Store string
SUB	SUB reg, reg SUB mem, reg SUB reg, mem SUB reg, immed SUB mem, immed SUB accum, immed	Subtract	*			*	*	*		*	*
TEST	TEST reg, reg TEST mem, reg TEST reg, mem TEST reg, immed TEST mem, immed TEST accum, immed	Test individual bits	0			*	*	?	*	0
WAIT WAIT	WAIT	Wait for coprocessor
XCHG	XCHG reg, reg XCHG mem, reg XCHG reg, mem	Exchange
XLAT	XLAT XLAT mem XLAT segreg:mem	Translate byte
XOR	XOR reg, reg XOR mem, reg XOR reg, mem XOR reg, immed XOR mem, immed XOR accum, immed	Exclusive OR	0			*	*	?	*	0

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