/* Copyright (C) 1991, 93, 96, 97, 98, 99, 2000 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. */ #include <features.h> #include <sys/syscall.h> #define _ASM 1 #define _SETJMP_H #include <bits/setjmp.h> #define ENV(base,reg) [%base + (reg * 4)] #define ST_FLUSH_WINDOWS 3 #define RW_FP [%fp + 0x48] .global __longjmp .type __longjmp,%function .align 4 __longjmp: .register %g2, #scratch .register %g3, #scratch /* Store our arguments in global registers so we can still * use them while unwinding frames and their register windows. */ ld ENV(o0,JB_FP), %g3 /* Cache target FP in register %g3. */ mov %o0, %g1 /* ENV in %g1 */ orcc %o1, %g0, %g2 /* VAL in %g2 */ be,a 0f /* Branch if zero; else skip delay slot. */ mov 1, %g2 /* Delay slot only hit if zero: VAL = 1. */ 0: xor %fp, %g3, %o0 add %fp, 512, %o1 andncc %o0, 4095, %o0 bne .Lthread cmp %o1, %g3 bl .Lthread /* Now we will loop, unwinding the register windows up the stack * until the restored %fp value matches the target value in %g3. */ .Lloop: cmp %fp, %g3 /* Have we reached the target frame? */ bl,a .Lloop /* Loop while current fp is below target. */ restore /* Unwind register window in delay slot. */ be,a .Lfound /* Better have hit it exactly. */ ld ENV(g1,JB_SP), %o0 /* Delay slot: extract target SP. */ .Lthread: /* * Do a "flush register windows trap". The trap handler in the * kernel writes all the register windows to their stack slots, and * marks them all as invalid (needing to be sucked up from the * stack when used). This ensures that all information needed to * unwind to these callers is in memory, not in the register * windows. */ ta ST_FLUSH_WINDOWS ld ENV(g1,JB_PC), %o7 /* Set return PC. */ ld ENV(g1,JB_SP), %fp /* Set saved SP on restore below. */ sub %fp, 64, %sp /* Allocate a register frame. */ st %g3, RW_FP /* Set saved FP on restore below. */ retl restore %g2, 0, %o0 /* Restore values from above register frame. */ .Lfound: /* We have unwound register windows so %fp matches the target. */ mov %o0, %sp /* OK, install new SP. */ .Lsp_ok: ld ENV(g1,JB_PC), %o0 /* Extract target return PC. */ jmp %o0 + 8 /* Return there. */ mov %g2, %o0 /* Delay slot: set return value. */ .size __longjmp,.-__longjmp libc_hidden_def(__longjmp)