- test %rsi,%rsi
- jz 1f /* if save == 0, just goto setjmp */
- movq %rsi,64(%rdi) /* move save -> jmp_buf[8] */
- addq $72,%rdi /* add sizeof(jmp_buf) to rdi */
- movl $0,%esi /* arg2 = 0 */
- movl $2,%edx /* arg3 = 2 */
- call sigprocmask /* sigprocmask(jmp_buf, 0, 2) */