x86

the Von Neumann architecture

머신 스택

*

> 범용 레지스터

AMD64는 범용 레지스터를 16개로 늘렸다

%eax # accumulator

%ebx

%ecx # count

%edx # data

%esi

%edi

%ebp

base pointer

프레임 포인터

스택 프레임

%esp

stack pointer

> can only be accessed through special instructions

인스트럭션 포인터

프로그램 카운터(pc, program counter)

%eip

플래그 레지스터

status register

%eglags

상태 플래그

* 오퍼랜드

> 값(immediate mode)

$숫자

to load direct values into registers or memory locations

can only be a source operand

c.f. direct addressing mode

> 레지스터(register addressing mode)

%..

> memory address references

ADDRESS_OR_OFFSET(%BASE_OR_OFFSET,%INDEX,MULTIPLIER)

FINAL ADDRESS = ADDRESS_OR_OFFSET + %BASE_OR_OFFSET + MULTIPLIER * %INDEX

- direct addressing mode

ADDRESS_OR_OFFSET # the value at memory address ADDRESS_OR_OFFSET

c.f. immediate mode

- indexed addressing mode

ADDRESS_OR_OFFSET(,%INDEX,WORDSIZE)

You can use any general-purpose register as the index register

a constant multiplier of 1, 2, or 4(8)

- indirect addressing mode

(%BASE_OR_OFFSET)

c.f. (%eax,%edi,1) # indexed indirect addressing mode

- base pointer addressing mode

포인터

ADDRESS_OR_OFFSET(%BASE_OR_OFFSET)

구조체 멤버 액세스?

ADDRESS_OR_OFFSET(%ebp)

access to the current stack frame elements(parameters, local variables)

* 전송 명령

mov(l)

값을 복사(대입)

movsx

movzx

push(l)

pop(l)

lea(l)

enter

leave

cltd(cdq) // ax -> dx

sete // Equal(ZF=1)

*

cmp(l) // Equal(ZF=1)

c.f. sub

the result of the comparison is stored in the status register

test

c.f. and

* 비트 연산 명령

and(l)

or(l)

xor(l)

not(l)

sal(l)

sar(l)

shr(l)

* 산술 연산 명령

add(l)

add the source operand from/to/by the destination operand and and save the result in the destination operand

캐리 플래그(CF)

sub(l)

imul(l)

idiv(l)

the dividend be in %eax, and %edx be zero, and the quotient is then transferred to %eax and the remainder to %edx. However, the divisor can be any register or memory location

inc(l)

dec(l)

neg(l)

* 연산의 제어

flow control instructions

jmp

conditional jump

jnz

unconditional jump

ZF(Zero Flag)

je

jg

jge

jl

jle

call

cdecl

stdcall

fastcall(or register call)

ret