Question

I ran objdump -r on an object file and got the following output. What do each of the columns represent here? I might have missed it, but the documentation doesn’t specify.

simple.o:     file format elf64-x86-64


Disassembly of section .text:
0000000000000000 <main>:
   0:   55                      push   %rbp
   1:   48 89 e5                mov    %rsp,%rbp
   4:   48 83 ec 30             sub    $0x30,%rsp
   8:   64 48 8b 04 25 28 00    mov    %fs:0x28,%rax
   f:   00 00 
  11:   48 89 45 f8             mov    %rax,-0x8(%rbp)
  15:   31 c0                   xor    %eax,%eax
  17:   c7 45 d8 00 00 00 00    movl   $0x0,-0x28(%rbp)
  1e:   eb 64                   jmp    84 <main+0x84>
  20:   8b 45 d8                mov    -0x28(%rbp),%eax
  23:   89 c7                   mov    %eax,%edi
  25:   e8 00 00 00 00          callq  2a <main+0x2a>
                        26: R_X86_64_PC32       foo-0x4
  2a:   89 45 dc                mov    %eax,-0x24(%rbp)
  2d:   8b 55 dc                mov    -0x24(%rbp),%edx
  30:   48 8d 45 e0             lea    -0x20(%rbp),%rax

etc

Answer 1

Isn’t it self explanatory:

Offset, Machine code, Corresponding Assembly code