sysdeps/m68k/__longjmp.c

   1 /* Copyright (C) 1991, 92, 93, 94, 95, 97 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, write to the Free
  16    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  17    02111-1307 USA.  */
  18
  19 #include <setjmp.h>
  20 #include <stdlib.h>
  21
  22 /* Jump to the position specified by ENV, causing the
  23    setjmp call there to return VAL, or 1 if VAL is 0.  */
  24 void
  25 __longjmp (__jmp_buf env, int val)
  26 {
  27   /* This restores the FP and SP that setjmp's caller had,
  28      and puts the return address into A0 and VAL into D0. */
  29
  30 #if     defined(__HAVE_68881__) || defined(__HAVE_FPU__)
  31   /* Restore the floating-point registers.  */
  32   asm volatile("fmovem%.x %0, %/fp0-%/fp7" :
  33                /* No outputs.  */ : "g" (env[0].__fpregs[0]));
  34 #endif
  35
  36   /* Put VAL in D0.  */
  37   asm volatile("move%.l %0, %/d0" : /* No outputs.  */ :
  38                "g" (val == 0 ? 1 : val) : "d0");
  39
  40   asm volatile(/* Restore the data and address registers.  */
  41                "movem%.l %0, %/d1-%/d7/%/a0-%/a7\n"
  42                /* Return to setjmp's caller.  */
  43 #ifdef __motorola__
  44                "jmp (%/a0)"
  45 #else
  46                "jmp %/a0@"
  47 #endif
  48                : /* No outputs.  */ : "g" (env[0].__dregs[0])
  49                /* We don't bother with the clobbers,
  50                   because this code always jumps out anyway.  */
  51                );
  52
  53   /* Avoid `volatile function does return' warnings.  */
  54   for (;;);
  55 }