dotfiles/objdump at master · ivanria/dotfiles · GitHub

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ivr@nout:/tmp$ cat test.c
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main(int argc, char *argv[])
{
	char *string = "hello world\n";

	for (; *string != '\0'; string++)
		printf("%c", *string);
	return 0;
}
ivr@nout:/tmp$ gcc test.c
ivr@nout:/tmp$ ./a.out
hello world
ivr@nout:/tmp$ gcc -S test.c
ivr@nout:/tmp$
ivr@nout:/tmp$
ivr@nout:/tmp$ cat test.s
	.file	"test.c"
	.section	.rodata
.LC0:
	.string	"hello world\n"
	.text
	.globl	main
	.type	main, @function
main:
.LFB0:
	.cfi_startproc
	pushq	%rbp
	.cfi_def_cfa_offset 16
	.cfi_offset 6, -16
	movq	%rsp, %rbp
	.cfi_def_cfa_register 6
	subq	$32, %rsp
	movl	%edi, -20(%rbp)
	movq	%rsi, -32(%rbp)
	movq	$.LC0, -8(%rbp)
	jmp	.L2
.L3:
	movq	-8(%rbp), %rax
	movzbl	(%rax), %eax
	movsbl	%al, %eax
	movl	%eax, %edi
	call	putchar
	addq	$1, -8(%rbp)
.L2:
	movq	-8(%rbp), %rax
	movzbl	(%rax), %eax
	testb	%al, %al
	jne	.L3
	movl	$0, %eax
	leave
	.cfi_def_cfa 7, 8
	ret
	.cfi_endproc
.LFE0:
	.size	main, .-main
	.ident	"GCC: (Debian 4.7.2-5) 4.7.2"
	.section	.note.GNU-stack,"",@progbits
ivr@nout:/tmp$ objcopy --only-section=.text --output-target binary test.o test.bin
ivr@nout:/tmp$ objcopy --only-section=.text --output-target binary test.o test.bin
ivr@nout:/tmp$
ivr@nout:/tmp$ objdump -D -b binary -m i386:x86-64 test.bin

test.bin:     file format binary


Disassembly of section .data:

0000000000000000 <.data>:
   0:	55                   	push   %rbp
   1:	48 89 e5             	mov    %rsp,%rbp
   4:	48 83 ec 20          	sub    $0x20,%rsp
   8:	89 7d ec             	mov    %edi,-0x14(%rbp)
   b:	48 89 75 e0          	mov    %rsi,-0x20(%rbp)
   f:	48 c7 45 f8 00 00 00 	movq   $0x0,-0x8(%rbp)
  16:	00
  17:	eb 16                	jmp    0x2f
  19:	48 8b 45 f8          	mov    -0x8(%rbp),%rax
  1d:	0f b6 00             	movzbl (%rax),%eax
  20:	0f be c0             	movsbl %al,%eax
  23:	89 c7                	mov    %eax,%edi
  25:	e8 00 00 00 00       	callq  0x2a
  2a:	48 83 45 f8 01       	addq   $0x1,-0x8(%rbp)
  2f:	48 8b 45 f8          	mov    -0x8(%rbp),%rax
  33:	0f b6 00             	movzbl (%rax),%eax
  36:	84 c0                	test   %al,%al
  38:	75 df                	jne    0x19
  3a:	b8 00 00 00 00       	mov    $0x0,%eax
  3f:	c9                   	leaveq
  40:	c3                   	retq
ivr@nout:/tmp$