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/*	$NetBSD: rtld_start.S,v 1.9 2002/10/05 11:59:05 mycroft Exp $	*/
/* $FreeBSD$ */

/*
 * Copyright 1997 Michael L. Hitch <mhitch@montana.edu>
 * Portions copyright 2002 Charles M. Hannum <root@ihack.net>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <machine/asm.h>

.globl _C_LABEL(_rtld_relocate_nonplt_self)
.globl _C_LABEL(_rtld)

LEAF(rtld_start)
	.abicalls
	.set	noreorder

	.cpload t9
	addu	sp, sp, -16		/* adjust stack pointer		*/
					/*	keep it aligned		*/
	.cprestore 0			/* -> 0(sp) for gp		*/
					/* -> 4(sp) for atexit		*/
					/* -> 8(sp) for obj_main	*/
	move	s0,a0			/* save stack pointer from a0	*/
	move	s1,a3			/* save ps_strings pointer	*/

	la	a1, 1f
	bal	1f
	nop
1:	subu	a1, ra, a1		/* relocbase */
	la	t9,_C_LABEL(_rtld_relocate_nonplt_self)
	move	s2,a1
	la	a0,_DYNAMIC
	addu	t9, a1, t9
	jalr	t9
	addu	a0, a1, a0		/* &_DYNAMIC */


	move	a0, s0			/* stack pointer		*/
	addu	a1, sp, 4		/* &exit_proc			*/
	addu	a2, sp, 8		/* &objp			*/
	addu	sp, sp, -16		/* arguments slot		*/
	jal	_C_LABEL(_rtld)		/* v0 = _rtld(sp, exit_proc, objp) */
	nop
	addu	sp, sp, 16		

	move	a0, s0			/* arguments pointer		*/
	move	a3, s1			/* arguments pointer		*/
	lw	a1, 4(sp)		/* our atexit function		*/
	lw	a2, 8(sp)		/* obj_main entry		*/
	addu	sp, sp, 16		/* readjust stack		*/
	move	t9,v0
	move	a2,s1			/* restore ps_strings		*/
	jr	t9			/* _start(ap, cleanup, obj, ps_strings);	*/
	nop

END(rtld_start)

	.globl	_rtld_bind_start
	.ent	_rtld_bind_start
_rtld_bind_start:
	/* ABI conventions for stubs:
	 *   t8 contains symbol index 
	 *   t7 contains return address 
	 */
	.frame sp, 0, ra		/* satisfy compiler		*/

	move	v1,gp			/* save old GP			*/
	add	t9,8			/* modify T9 to point at .cpload */
	.cpload	t9
	subu	sp,48			/* save arguments and sp value	*/
	.cprestore 36
	sw	a0,16(sp)
	sw	a1,20(sp)
	sw	a2,24(sp)
	sw	a3,28(sp)
	sw	s0,32(sp)
	sw	t7,40(sp)
	move	s0,sp
	move	a0,v1			/* old GP			*/
	subu	a0,a0,0x7ff0		/* The offset of $gp from the	*/
					/* beginning of the .got section: */
					/* $gp = .got + 0x7ff0, so	*/
					/* .got = $gp - 0x7ff0		*/
					/* Simple math as you can see.	*/

	lw	a0,4(a0)		/* object = pltgot[1] & 0x7fffffff */
	and	a0,a0,0x7fffffff
	move	a1,t8			/* symbol index */
					
	jal	_C_LABEL(_mips_rtld_bind)
	nop
	move	sp,s0
	lw	ra,40(sp)
	lw	a0,16(sp)
	lw	a1,20(sp)
	lw	a2,24(sp)
	lw	a3,28(sp)
	lw	s0,32(sp)
	addu	sp,48
	move	t9,v0
	jr	t9
	nop
	.end	_rtld_bind_start
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