ports/sysdeps/m68k/__longjmp.c

   1 /* Copyright (C) 1991, 1992, 1993, 1994, 1995, 1997, 2009
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library.  If not, see
  17    <http://www.gnu.org/licenses/>.  */
  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 #ifdef CHECK_SP
  31   CHECK_SP (env[0].__sp);
  32 #endif
  33
  34 #if     defined(__HAVE_68881__) || defined(__HAVE_FPU__)
  35   /* Restore the floating-point registers.  */
  36   asm volatile("fmovem%.x %0, %/fp0-%/fp7" :
  37                /* No outputs.  */ : "g" (env[0].__fpregs[0]));
  38 #elif defined (__mcffpu__)
  39   asm volatile("fmovem %0, %/fp0-%/fp7" :
  40                /* No outputs.  */ : "m" (env[0].__fpregs[0]));
  41 #endif
  42
  43   /* Put VAL in D0.  */
  44   asm volatile("move%.l %0, %/d0" : /* No outputs.  */ :
  45                "g" (val == 0 ? 1 : val) : "d0");
  46
  47   asm volatile(/* Restore the data and address registers.  */
  48                "movem%.l %0, %/d1-%/d7/%/a0-%/a7\n"
  49                /* Return to setjmp's caller.  */
  50 #ifdef __motorola__
  51                "jmp (%/a0)"
  52 #else
  53                "jmp %/a0@"
  54 #endif
  55                : /* No outputs.  */ : "g" (env[0].__dregs[0])
  56                /* We don't bother with the clobbers,
  57                   because this code always jumps out anyway.  */
  58                );
  59
  60   /* Avoid `volatile function does return' warnings.  */
  61   for (;;);
  62 }