x86-64 Reference Sheet (GNU assembler format)
Instructions
Data movement
movq Src, Dest Dest = Src
movsbq Src,Dest Dest (quad) = Src (byte), sign-extend
movzbq Src,Dest Dest (quad) = Src (byte), zero-extend
Conditional move
cmove Src, Dest Equal / zero
cmovne Src, Dest Not equal / not zero
cmovs Src, Dest Negative
cmovns Src, Dest Nonnegative
cmovg Src, Dest Greater (signed >)
cmovge Src, Dest Greater or equal (signed ≥)
cmovl Src, Dest Less (signed <)
cmovle Src, Dest Less or equal (signed ≤)
cmova Src, Dest Above (unsigned >)
cmovae Src, Dest Above or equal (unsigned ≥)
cmovb Src, Dest Below (unsigned <)
cmovbe Src, Dest Below or equal (unsigned ≤)
Control transfer
cmpq Src2, Src1 Sets CCs Src1 Src2
testq Src2, Src1 Sets CCs Src1 & Src2
jmp label jump
je label jump equal
jne label jump not equal
js label jump negative
jns label jump non-negative
jg label jump greater (signed >)
jge label jump greater or equal (signed ≥)
jl label jump less (signed <)
jle label jump less or equal (signed ≤)
ja label jump above (unsigned >)
jb label jump below (unsigned <)
pushq Src %rsp = %rsp 8, Mem[%rsp] = Src
popq Dest Dest = Mem[%rsp], %rsp = %rsp + 8
call label push address of next instruction, jmp label
ret %rip = Mem[%rsp], %rsp = %rsp + 8
Arithmetic operations
leaq Src, Dest Dest = address of Src
incq Dest Dest = Dest +1
decq Dest Dest = Dest −1
addq Src, Dest Dest = Dest +Src
subq Src, Dest Dest = Dest −Src
imulq Src, Dest Dest = Dest ∗Src
xorq Src, Dest Dest = Dest ˆSrc
orq Src, Dest Dest = Dest |Src
andq Src, Dest Dest = Dest &Src
negq Dest Dest = −Dest
notq Dest Dest = ∼Dest
salq k, Dest Dest = Dest ≪k
sarq k, Dest Dest = Dest ≫k(arithmetic)
shrq k, Dest Dest = Dest ≫k(logical)
Addressing modes
•Immediate
$val Val
val: constant integer value
movq $7, %rax
•Normal
(R) Mem[Reg[R]]
R: register R specifies memory address
movq (%rcx), %rax
•Displacement
D(R) Mem[Reg[R]+D]
R: register specifies start of memory region
D: constant displacement D specifies offset
movq 8(%rdi), %rdx
•Indexed
D(Rb,Ri,S) Mem[Reg[Rb]+S*Reg[Ri]+D]
D: constant displacement 1, 2, or 4 bytes
Rb: base register: any of 8 integer registers
Ri: index register: any, except %esp
S: scale: 1, 2, 4, or 8
movq 0x100(%rcx,%rax,4), %rdx
Instruction suffixes
bbyte
wword (2 bytes)
llong (4 bytes)
qquad (8 bytes)
Condition codes
CF Carry Flag
ZF Zero Flag
SF Sign Flag
OF Overflow Flag
Integer registers
%rax Return value
%rbx Callee saved
%rcx 4th argument
%rdx 3rd argument
%rsi 2nd argument
%rdi 1st argument
%rbp Callee saved
%rsp Stack pointer
%r8 5th argument
%r9 6th argument
%r10 Scratch register
%r11 Scratch register
%r12 Callee saved
%r13 Callee saved
%r14 Callee saved
%r15 Callee saved