ref: 8188b4f4f0e07b6669e6ae3c6c1099af917eaab4
dir: /sys/src/libc/amd64/setjmp.s/
TEXT longjmp(SB), $0 MOVL r+8(FP), AX CMPL AX, $0 JNE ok /* ansi: "longjmp(0) => longjmp(1)" */ MOVL $1, AX /* bless their pointed heads */ ok: MOVQ 0(RARG), SP /* restore sp */ MOVQ 8(RARG), BX /* put return pc on the stack */ MOVQ BX, 0(SP) RET TEXT setjmp(SB), $0 MOVQ SP, 0(RARG) /* store sp */ MOVQ 0(SP), BX /* store return pc */ MOVQ BX, 8(RARG) MOVL $0, AX /* return 0 */ RET