打印函數堆棧幀信息

例子

#include <stdio.h>
int func(int a, int b)
{
    int c = a * b;
    printf("c is %d\n", c);
}

int main(void) 
{
    func(1, 2);
    return 0;
}

技巧

使用gdb調試程序時，可以使用“i frame”命令（i是info命令縮寫）顯示函數堆棧幀信息。以上面程序為例：

Breakpoint 1, func (a=1, b=2) at a.c:5
5               printf("c is %d\n", c);
(gdb) i frame
Stack level 0, frame at 0x7fffffffe590:
 rip = 0x40054e in func (a.c:5); saved rip = 0x400577
 called by frame at 0x7fffffffe5a0
 source language c.
 Arglist at 0x7fffffffe580, args: a=1, b=2
 Locals at 0x7fffffffe580, Previous frame's sp is 0x7fffffffe590
 Saved registers:
  rbp at 0x7fffffffe580, rip at 0x7fffffffe588
(gdb) i registers
rax            0x2      2
rbx            0x0      0
rcx            0x0      0
rdx            0x7fffffffe688   140737488348808
rsi            0x2      2
rdi            0x1      1
rbp            0x7fffffffe580   0x7fffffffe580
rsp            0x7fffffffe560   0x7fffffffe560
r8             0x7ffff7dd4e80   140737351863936
r9             0x7ffff7dea560   140737351951712
r10            0x7fffffffe420   140737488348192
r11            0x7ffff7a35dd0   140737348066768
r12            0x400440 4195392
r13            0x7fffffffe670   140737488348784
r14            0x0      0
r15            0x0      0
rip            0x40054e 0x40054e <func+24>
eflags         0x202    [ IF ]
cs             0x33     51
ss             0x2b     43
ds             0x0      0
es             0x0      0
fs             0x0      0
gs             0x0      0
(gdb) disassemble func
Dump of assembler code for function func:
   0x0000000000400536 <+0>:     push   %rbp
   0x0000000000400537 <+1>:     mov    %rsp,%rbp
   0x000000000040053a <+4>:     sub    $0x20,%rsp
   0x000000000040053e <+8>:     mov    %edi,-0x14(%rbp)
   0x0000000000400541 <+11>:    mov    %esi,-0x18(%rbp)
   0x0000000000400544 <+14>:    mov    -0x14(%rbp),%eax
   0x0000000000400547 <+17>:    imul   -0x18(%rbp),%eax
   0x000000000040054b <+21>:    mov    %eax,-0x4(%rbp)
=> 0x000000000040054e <+24>:    mov    -0x4(%rbp),%eax
   0x0000000000400551 <+27>:    mov    %eax,%esi
   0x0000000000400553 <+29>:    mov    $0x400604,%edi
   0x0000000000400558 <+34>:    mov    $0x0,%eax
   0x000000000040055d <+39>:    callq  0x400410 <printf@plt>
   0x0000000000400562 <+44>:    leaveq
   0x0000000000400563 <+45>:    retq
End of assembler dump.

可以看到執行“i frame”命令後，輸出了當前函數堆棧幀的地址，指令寄存器的值，局部變量地址及值等信息，可以對照當前寄存器的值和函數的彙編指令看一下。
參見gdb手冊.

貢獻者

nanxiao