怎样高效写汇编代码

C语言中有变量的概念,而汇编里没有。变量指定了内存中占用的字节数,对它的读写可以通过其地址来引用 ,所以我们可以像C语言一样定义数据类型,并将变量名写入汇编代码中。之后在将变量名替换为地址。
举例

.section .rodata
	.LC0:.string "%d,%d\n"

.text
.global main
main:
	pushl %ebp
	movl %esp,%ebp
	
	subl $12,%esp
	movl $1,a1
	movl $2,b1
	
	pushl b1
	pushl a1
	pushl $.LC0
	call printf
	addl $12,%esp
	
	movl a1,%eax
	movl %eax,tmp
	movl b1,%eax
	movl %eax,a1
	movl tmp,%eax
	movl %eax,b1
	
	pushl b1
	pushl a1
	pushl $.LC0
	call printf
	addl $12,%esp
	
	movl $0,%eax
	leave
	ret

将a1改为-4(%ebp),将b1改为-8(%ebp),将tmp改为-12(%ebp)

.section .rodata
	.LC0:.string "%d,%d\n"

.text
.global main
main:
	pushl %ebp
	movl %esp,%ebp
	
	subl $12,%esp
	movl $1,-4(%ebp)
	movl $2,-8(%ebp)
	
	pushl -8(%ebp)
	pushl -4(%ebp)
	pushl $.LC0
	call printf
	addl $12,%esp
	
	movl -4(%ebp),%eax
	movl %eax,-12(%ebp)
	movl -8(%ebp),%eax
	movl %eax,-4(%ebp)
	movl -12(%ebp),%eax
	movl %eax,-8(%ebp)
	
	pushl -8(%ebp)
	pushl -4(%ebp)
	pushl $.LC0
	call printf
	addl $12,%esp
	
	movl $0,%eax
	leave
	ret
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转载自blog.csdn.net/pk_20140716/article/details/103344905