src/setjmp/x86_64/setjmp.s

   1 /* Copyright 2011-2012 Nicholas J. Kain, licensed under standard MIT license */
   2 .global __setjmp
   3 .global _setjmp
   4 .global setjmp
   5 .type __setjmp,@function
   6 .type _setjmp,@function
   7 .type setjmp,@function
   8 __setjmp:
   9 _setjmp:
  10 setjmp:
  11         mov %rbx,(%rdi)         /* rdi is jmp_buf, move registers onto it */
  12         mov %rbp,8(%rdi)
  13         mov %r12,16(%rdi)
  14         mov %r13,24(%rdi)
  15         mov %r14,32(%rdi)
  16         mov %r15,40(%rdi)
  17         lea 8(%rsp),%rdx        /* this is our rsp WITHOUT current ret addr */
  18         mov %rdx,48(%rdi)
  19         mov (%rsp),%rdx         /* save return addr ptr for new rip */
  20         mov %rdx,56(%rdi)
  21         xor %eax,%eax           /* always return 0 */
  22         ret