__longjmp.c

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/* Copyright (C) 1991, 1992, 1993 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., 675 Mass Ave,
Cambridge, MA 02139, USA.  */

#include <ansidecl.h>
#include <setjmp.h>
#include <stdlib.h>

#ifndef	__GNUC__
  #error This file uses GNU C extensions; you must compile with GCC.
#endif

/* Jump to the position specified by ENV, causing the
   setjmp call there to return VAL, or 1 if VAL is 0.  */
__NORETURN
void
DEFUN(__longjmp, (env, val), CONST jmp_buf env AND int val)
{
  /* This restores the FP and SP that setjmp's caller had,
     and puts the return address into A0 and VAL into D0. */

#if	defined(__HAVE_68881__) || defined(__HAVE_FPU__)
  /* Restore the floating-point registers.  */
  asm volatile("fmovem%.x %0, fp0-fp7" :
	       /* No outputs.  */ : "g" (env[0].__fpregs[0]) :
	       "fp0", "fp1", "fp2", "fp3", "fp4", "fp5", "fp6", "fp7");
#endif

  /* Put VAL in D0.  */
  asm volatile("move%.l %0, d0" : /* No outputs.  */ :
	       "g" (val == 0 ? 1 : val) : "d0");

  asm volatile(/* Restore the data and address registers.  */
	       "movem%.l %0, d1-d7/a0-a7\n"
	       /* Return to setjmp's caller.  */
#ifdef __motorola__
	       "jmp (a0)"
#else
	       "jmp a0@"
#endif
	       : /* No outputs.  */ : "g" (env[0].__dregs[0])
	       /* We don't bother with the clobbers,
		  because this code always jumps out anyway.  */
	       );

  /* This call avoids `volatile function does return' warnings.  */
  abort ();
}