1.第一个at&a 64汇编

  1 .section    .data
  2 strFormat:
  3 .asciz "%s\n"
  4 strUseLibc:
  5 .asciz "Hi, If you see me, you called c lib :)"
  6 strUseSyscall:
  7 .asciz "And if you see me, you called syscall.\n"
  8 endOfStrUseSyscall:
  9 
 10 .section    .text
 11 .globl  _start
 12 _start:
 13 # 函数调用的传参已经不再单纯使用压栈的方式
 14 movq    $strFormat, %rdi
 15 movq    $strUseLibc, %rsi
 16 call    printf
 17 
 18 # 系统调用的寄存器已经改变，int 0x80 也被syscall 替代
 19 movq    $1, %rdi
 20 movq    $strUseSyscall, %rsi
 21 movq    $(endOfStrUseSyscall-strUseSyscall), %rdx
 22 movq    $1, %rax
 23 syscall
 24 
 25 #另外系统调用的编号也不同了
 26 movq    $127, %rdi      # 故意返回一个非0 值
 27 movq    $60, %rax
 28 syscall

 

2 从c 转成汇编，再编译成bin 

GCC 编译的背后

http://tinylab.org/behind-the-gcc-compiler/

1 #include <stdio.h>
2 #include <unistd.h>
3 
4 int  sum(int a) {
5         return a;
6 }
7 int main() {
8         int b = 0;
9         b = sum(1);
10         printf("hello:%d\n", b);
11         _exit(0);
12 }

1 gcc -S  test.c -fno-asynchronous-unwind-tables -fno-exceptions -fno-stack-protector
2 sed -i -e "s#main#_start#g" test.s
3 gcc -c test.s
4 #ld -o test test.o   /usr/lib/x86_64-linux-gnu/crt1.o /usr/lib/x86_64-linux-gnu/crti.o /usr/lib/x86_64-linux-gnu/crtn.o  -lc --dynamic-linker /lib64/ld-linux-x86-64.so.2
5 ld -o test test.o   -lc --dynamic-linker /lib64/ld-linux-x86-64.so.2

 

标签：汇编,x86,int,64,linux,test,movq
来源： https://www.cnblogs.com/mysqlinternal/p/12736401.html