Stack

1. Push and pop operations

           push  longthing                       pop longthing
   ;equivalent code                      ;equivalent code
           subl  $4,%esp                         movl  (%esp),longthing
           movl  longthing,(%esp)                addl  $4,%esp

2. Call and return operations

           call function                         ret
    next:  ...                           ;equivalent code using %eax
    ;equivalent code                             pop   %eax
           subl  $4,%esp                         jmp   *eax
           lea   next,(%esp)             ;equivalent code using %eax
           jmp   function                        movl  %esp,%eax
    next:                                        addl  $4,%esp
                                                 jmp   *(%eax)




[stafford@localhost stack]$ cat hello.c
extern int printf (const char *, ...);
main()
{
    int i = 10, j = 20;
    printf("Hello  world, &i = %08x, &j = %08x, sp-12 = %08x, sp-16 = %08x, sp-20 = %08x, sp-24 = %08x\n\
           sp-28 = %08x, sp-32 = %08x, sp-36 = %08x, sp-40 = %08x, sp-44 = %08x, sp-48 = %08x\n\
           sp-52 = %08x, sp-56 = %08x, sp-60 = %08x, sp-64 = %08x, sp-68 = %08x, sp-70 = %08x\n", &i, &j);
}
[stafford@localhost stack]$ gcc -S -O0 hello.c
[stafford@localhost stack]$ gcc hello.s
[stafford@localhost stack]$ more hello.s
        .file   "hello.c"
        .section        .rodata
        .align 4
.LC0:
        .ascii  "Hello  world, *i = %08x,  "
        .string "  *j = %08x, sp-12 = %08x, sp-16 = %08x, sp-20 = %08x, sp-24 = %08x\n       
		 sp-28 = %08x, sp-32 = %08x, sp-36 = %08x, sp-40 = %08x, sp-44 = %08x, sp-48 = %08x\n           
		 sp-52 = %08x, sp-56 = %08x, sp-60 = %08x, sp-64 = %08x, sp-68 = %08x, sp-70 = %08x\n"
        .text
.globl main
        .type   main, @function
main:
        leal    4(%esp), %ecx
        andl    $-16, %esp
        pushl   -4(%ecx)
        pushl   %ebp
        movl    %esp, %ebp
        pushl   %ecx
        subl    $36, %esp
        movl    $10, -8(%ebp)
        movl    $20, -12(%ebp)
        leal    -12(%ebp), %eax
        movl    %eax, 8(%esp)
        leal    -8(%ebp), %eax
        movl    %eax, 4(%esp)
        movl    $.LC0, (%esp)
        call    printf
        addl    $36, %esp
        popl    %ecx
        popl    %ebp
        leal    -4(%ecx), %esp
        ret
        .size   main, .-main
        .ident  "GCC: (GNU) 4.1.2 20070925 (Red Hat 4.1.2-27)"
        .section        .note.GNU-stack,"",@progbits
[stafford@localhost stack]$ ./a.out
Hello  world, &i = bfd91d50,    &j = bfd91d4c, sp-12 = 08048419, sp-16 = 00667ce5, sp-20 = bfd91dfc, sp-24 = bfd91d68
           sp-28 = 00000014, sp-32 = 0000000a, sp-36 = bfd91d70, sp-40 = bfd91dc8, sp-44 = 00651f70, sp-48 = 00638ca0
           sp-52 = 08048400, sp-56 = bfd91dc8, sp-60 = 00651f70, sp-64 = 00000001, sp-68 = bfd91df4, sp-70 = bfd91dfc
[stafford@localhost stack]$