jmp.S

.global psetjmp
.type psetjmp,@function
psetjmp:
	mov %rbx,(%rdi)         /* rdi is jmp_buf, move registers onto it */
	mov %rbp,8(%rdi)
	mov %r12,16(%rdi)
	mov %r13,24(%rdi)
	mov %r14,32(%rdi)
	mov %r15,40(%rdi)
	lea 8(%rsp),%rdx        /* this is our rsp WITHOUT current ret addr */
	mov %rdx,48(%rdi)
	mov (%rsp),%rdx         /* save return addr ptr for new rip */
	mov %rdx,56(%rdi)
	xor %eax,%eax           /* always return 0 */
	ret

.global plongjmp
.type plongjmp,@function
plongjmp:
	xor %eax,%eax
	cmp $1,%esi             /* CF = val ? 0 : 1 */
	adc %esi,%eax           /* eax = val + !val */
	mov (%rdi),%rbx         /* rdi is the jmp_buf, restore regs from it */
	mov 8(%rdi),%rbp
	mov 16(%rdi),%r12
	mov 24(%rdi),%r13
	mov 32(%rdi),%r14
	mov 40(%rdi),%r15
	mov 48(%rdi),%rsp
	jmp *56(%rdi)