glibc/sysdeps/i386/__longjmp.c
1995-02-18 01:27:10 +00:00

67 lines
1.9 KiB
C

/* Copyright (C) 1991, 1992, 1994, 1995 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. */
#ifndef __GNUC__
#error This file uses GNU C extensions; you must compile with GCC.
#endif
/* Put these global register declarations first, because we get an error if
they come after any function definition, including inlines which might
be in some header. */
#define REGS \
REG (bx);\
REG (si);\
REG (di);\
REG (bp);\
REG (sp)
#define REG(xx) register long int xx asm (#xx)
REGS;
#undef REG
#include <ansidecl.h>
#include <errno.h>
#include <setjmp.h>
#include <stdlib.h>
/* Jump to the position specified by ENV, causing the
setjmp call there to return VAL, or 1 if VAL is 0. */
void
DEFUN(__longjmp, (env, val),
__jmp_buf env AND int val)
{
/* We specify explicit registers because, when not optimizing,
the compiler will generate code that uses the frame pointer
after it's been munged. */
register CONST __typeof (env[0]) *e asm ("cx");
register int v asm ("ax");
e = env;
v = val == 0 ? 1 : val;
#define REG(xx) xx = (long int) e->__##xx
REGS;
asm volatile ("jmp %*%0" : : "g" (e->__pc), "a" (v));
/* NOTREACHED */
abort ();
}