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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 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 <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;
.align 4;
__longjmp: ; 
.type __longjmp ,@function; 

        /* 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