通过x86汇编语言

Question

我需要一些帮助来确定这些x86汇编语言的行。在第二个lea之后，％eax总是5并且％ebx会变成4吗？另外我不确定添加和比较是做什么的。任何帮助表示赞赏。

       mov    $0x5,%eax
       lea    -0x20(%ebp),%esi
       lea    -0x1(%eax),%ebx
       add    0x4(%esi,%ebx,4),%eax
       cmp    %eax,(%esi,%ebx,4)
       je     0x8048dce 

Answer 1

mov    $0x5,%eax             - sets eax to 5
lea    -0x20(%ebp),%esi      - loads the dword value at ebp-0x20 into esi
lea    -0x1(%eax),%ebx       - sets ebx to the value of eax-1 (i.e. 4)
add    0x4(%esi,%ebx,4),%eax - adds the dword value at esi+ebx*4+4 to eax
cmp    %eax,(%esi,%ebx,4)    - compares eax to the dword value at esi+ebx*4
je     0x8048dce             - branches if they are equal