1/* $NetBSD: rtld_start.S,v 1.7 2002/02/24 01:06:22 matt Exp $ */ 2 3/* 4 * Copyright 1996 Matt Thomas <matt@3am-software.com> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30#include <machine/asm.h> 31 32/* R9 contains the address of PS_STRINGS and since its caller saved, 33 * we can just use it. R6 has a backup copy of the stack pointer which 34 * we can use as well. Since the VAX has perfectly PIC code, we don't 35 * need to relocate anything upon startup. 36 */ 37ENTRY(_rtld_start, 0) 38 39 /* Allocate space on the stack for the cleanup and obj_main 40 * entries that _rtld() will provide for us. 41 */ 42 clrl %fp 43 subl2 $8,%sp 44 pushl %sp 45 46 calls $1,_rtld 47 48 movq (%sp)+,%r7 /* grab cleanup and obj_main into %r7/%r8 */ 49 jmp 2(%r0) /* jump to entry point + 2 */ 50 51/* 52 * Lazy binding entry point, called via PLT. 53 */ 54ALTENTRY(_rtld_bind_start) 55 pushr $0xff /* save R0-R7 */ 56 movq 32(%sp),%r0 /* get addresses of plt.got & reloc index */ 57 pushl (%r1) /* push relocation index */ 58 pushl %r0 /* push address of obj entry */ 59 calls $2,_rtld_bind 60 movpsl -(%sp) /* flush the instruction cache */ 61 pushab 1f /* by issuing an */ 62 rei /* rei. */ 631: movl %r0,36(%sp) /* save return address onto stack */ 642: bicw3 6(%fp),(%r0),%r0 /* does the entry mask save any additional regs */ 65 popr $0xff /* restore R0-R7 (cond flags not modified) */ 66 bneq 4f /* yes? do it the hard way */ 673: addl2 $4,%sp /* no? skip past plt.got on stack */ 68 addl2 $2,(%sp) /* skip past the mask */ 69 rsb /* and jump to it */ 704: addl2 $4,%sp 71 callg (%ap),*(%sp)+ /* return value from _rtld_bind() == actual */ 72 ret 73