glibc/sysdeps/alpha/bsd-_setjmp.S

/* BSD `_setjmp' entry point to `sigsetjmp (..., 0)'.  Alpha version.
Copyright (C) 1994, 1996 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.  */

/* This just does a tail-call to `__sigsetjmp (ARG, 0)'.
   We cannot do it in C because it must be a tail-call, so frame-unwinding
   in setjmp doesn't clobber the state restored by longjmp.  */

#include <sysdep.h>

ENTRY(_setjmp)
	ldgp	$29,0($27)
	.prologue 1
	bis	$31, $31, $17		/* Pass a second argument of zero.  */
	jmp	$31, __sigsetjmp	/* Call __sigsetjmp.  */
	END(_setjmp)