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/* 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <sysdep.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]
ENTRY(__longjmp)
/* 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 LOC(thread)
cmp %o1, %g3
bl LOC(thread)
/* Now we will loop, unwinding the register windows up the stack
until the restored %fp value matches the target value in %g3. */
LOC(loop):
cmp %fp, %g3 /* Have we reached the target frame? */
bl,a LOC(loop) /* Loop while current fp is below target. */
restore /* Unwind register window in delay slot. */
be,a LOC(found) /* Better have hit it exactly. */
ld ENV(g1,JB_SP), %o0 /* Delay slot: extract target SP. */
LOC(thread):
/*
* 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. */
LOC(found):
/* We have unwound register windows so %fp matches the target. */
mov %o0, %sp /* OK, install new SP. */
LOC(sp_ok):
ld ENV(g1,JB_PC), %o0 /* Extract target return PC. */
jmp %o0 + 8 /* Return there. */
mov %g2, %o0 /* Delay slot: set return value. */
END(__longjmp)
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