1/* $NetBSD: rtld_start64.S,v 1.2 2014/03/06 19:19:40 matt Exp $ */ 2 3/*- 4 * Copyright (C) 1998 Tsubai Masanari 5 * Portions copyright 2002 Charles M. Hannum <root@ihack.net> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31#include <machine/asm.h> 32 33 .globl _rtld_relocate_nonplt_self 34 .globl _rtld 35 36 .text 37ENTRY_NOPROFILE(_rtld_start) 38 mr %r23,%r3 // argc 39 mr %r24,%r4 // argv 40 mr %r25,%r5 // envp 41/* mr %r26,%r6 // obj (always 0) */ 42/* mr %r27,%r7 // cleanup (always 0) */ 43 mr %r28,%r8 // ps_strings 44 li %r0,0 45 stdu %r0,-64(%r1) // terminate stack chain 46 std %r2,40(%r1) // save TOC 47 std %r0,16(%r1) // ditto 48 49 bcl 20,31,1f 501: mflr %r30 51 ld %r3,0(%r2) // TOC[0] = &TOC 52 sub %r29,%r2,%r3 // compute relocbase 53 54 addis %r3,%r3,_DYNAMIC-1b@ha // get _DYNAMIC actual address 55 addi %r3,%r3,_DYNAMIC-1b@l 56 mr %r4,%r29 // r4 = relocbase 57 CALL(_rtld_relocate_nonplt_self) 58 59 addi %r3,%r1,48 // sp = <local variable space> 60 mr %r4,%r29 // r4 = relocbase 61 CALL(_rtld) // _start = _rtld(sp, relocbase) 62 63 ld %r0,0(%r3) // func address 64 ld %r2,8(%r3) // TOC address 65 ld %r11,16(%r3) // environment pointer 66 mtctr %r0 // so we can call it. 67 68 mr %r3,%r23 // argc 69 mr %r4,%r24 // argv 70 mr %r5,%r25 // envp 71 ld %r6,56(%r1) // obj = <localvar>[1] 72 ld %r7,48(%r1) // cleanup = <localvar>[0] 73 mr %r8,%r28 // ps_strings 74 75 bctrl // _start(argc, argv, envp, obj, cleanup, ps_strings) 76 nop 77 78 li %r0,1 // _exit() 79 sc 80END(_rtld_start) 81 82 .globl _rtld_bind 83 84/* 85 * %r0 has the index of the rela, %r12 has a pointer to the plt entry. 86 */ 87ENTRY_NOPROFILE(_rtld_bind_start) 88 std %r3,-72(%r1) // save argument register 89 std %r4,-64(%r1) // save argument register 90 std %r5,-56(%r1) // save argument register 91 std %r6,-48(%r1) // save argument register 92 std %r7,-40(%r1) // save argument register 93 std %r8,-32(%r1) // save argument register 94 std %r9,-24(%r1) // save argument register 95 std %r10,-16(%r1) // save argument register 96 std %r31,-8(%r1) // save register 97 stdu %r1,-(48+80)(%r1) // create back chain 98 mflr %r10 99 std %r10,16(%r1) // save LR 100 mfcr %r9 101 std %r9,8(%r1) // save CR to be safe 102 103 mr %r31, %r12 // save this across bind call 104 mr %r3, %r11 // obj 105 mr %r4, %r0 // reloff 106 107 CALL(_rtld_bind) // _rtld_bind(obj, reloff) 108 109 mtctr %r3 110 mr %r12,%r31 // restore r12 111 112 ld %r0,8(%r1) // get saved CR 113 mtcr %r0 // restore it 114 ld %r0,16(%r1) // get saved LR 115 mtlr %r0 // restore it 116 117 addi %r1,%r1,(48+80) // adjust stack 118 ld %r3,-72(%r1) // restore argument register 119 ld %r4,-64(%r1) // restore argument register 120 ld %r5,-56(%r1) // restore argument register 121 ld %r6,-48(%r1) // restore argument register 122 ld %r7,-40(%r1) // restore argument register 123 ld %r8,-32(%r1) // restore argument register 124 ld %r9,-24(%r1) // restore argument register 125 ld %r10,-16(%r1) // restore argument register 126 ld %r31,-8(%r1) // restore register 127 bctr 128END(_rtld_bind_start) 129