Assembly cmpl和jge未按exected运行,x86

Assembly cmpl和jge未按exected运行,x86,assembly,x86,cmp,Assembly,X86,Cmp,我必须翻译以下简单的C代码: int add(int a, int b); int main() { int a,b; a = 0; while(a<5) { a++; printi(a); prints("\n"); } return 0; } int add(int a, int b) { char cx = 'a'; int x = a-b; return x;

我必须翻译以下简单的C代码:

int add(int a, int b);

int main()
{
    int a,b;
    a = 0;
    while(a<5)
    {
        a++;
        printi(a);
        prints("\n");
    }
    return 0;
}

int add(int a, int b)
{
    char cx = 'a';
    int x = a-b;
    return x;
}
但是,该程序不输出任何内容。似乎我在while的check表达式附近犯了一个错误

指令
cmpl%edx,%eax
应将标志设置为0-5,即-5。因此,jge不应将其分支到.CH1。因此
-16(%ebp)
应该设置为1,然后它应该进入.CH2。像我一样=0,则应进入L1。我不知道我哪里做错了

指令
cmpl%edx,%eax
应将标志设置为0-5,即-5。j

没有。请记住,在AT&T语法中,操作数顺序是源、目标。您得到了
eax=5
edx=0
,因此
cmpl%edx,%eax
基于5-0设置标志,然后
jge
应该跳转

.section    .rodata
.LC0:
    .string "\n"
    .text
    .globl  main
    .type   main, @function
main:
    pushl   %ebp
    movl    %esp, %ebp
    andl    $-16, %esp
    movl    $0, -4(%ebp)
    movl    -4(%ebp), %eax
    movl    %eax, -12(%ebp)
.L0:
    movl    $5, %eax
    movl    -4(%ebp), %edx
    cmpl    %edx, %eax
    jge .CH1
.CH0:
    movl    $1, -16(%ebp)
    jmp .CH2
.CH1:
    movl    $0, -16(%ebp)
.CH2:
    movl    $0, %eax
    cmpl    -16(%ebp), %eax
    je  .L2
    jmp .L1
.L1:
    movl    -4(%ebp), %eax
    movl    %eax, -20(%ebp)
    movl    -20(%ebp), %eax
    movl    $1, %edx
    addl    %edx, %eax
    movl    %eax, -4(%ebp)
    movl    -4(%ebp), %eax
    movl    %eax, (%esp)
    call    printi
    movl    %eax, -24(%ebp)
    movl    $.LC0, (%esp)
    call    prints
    movl    %eax, -28(%ebp)
    jmp .L0
.L2:
    movl    $0, %eax
    leave
    ret
    .size   main, .-main
    .globl  add
    .type   add, @function
add:
    pushl   %ebp
    movl    %esp, %ebp
    movb    $97, -1(%ebp)
    movl    4(%ebp), %eax
    movl    8(%ebp), %edx
    subl    %edx, %eax
    movl    %eax, -9(%ebp)
    movl    -9(%ebp), %eax
    movl    %eax, -5(%ebp)
    movl    -5(%ebp), %eax
    leave
    ret
    .size   add, .-add