rtld_start.S revision 1.4
1 /* $NetBSD: rtld_start.S,v 1.4 2001/09/26 04:06:43 mycroft Exp $ */ 2 3 /*- 4 * Copyright (C) 1998 Tsubai Masanari 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 27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #include <machine/asm.h> 31 32 .globl _rtld_start 33 .globl _rtld 34 35 .text 36 37 _rtld_start: 38 stwu 1,-48(1) 39 stw 3,12(1) # argc 40 stw 4,16(1) # argv 41 stw 5,20(1) # envp 42 /* stw 6,24(1) # obj (always 0) */ 43 /* stw 7,28(1) # cleanup (always 0) */ 44 stw 8,32(1) # ps_strings 45 46 bl 1f 47 .long _GLOBAL_OFFSET_TABLE_-.-4 48 1: 49 mflr 3 50 lwz 4,0(3) 51 add 3,3,4 # r3 = _GLOBAL_OFFSET_TABLE_ - 4 52 53 dcbst 0,3 # sync i-cache with d-cache 54 sync 55 icbi 0,3 56 isync 57 58 addi 11,3,4 # r11 = (real) GOT 59 lwz 10,_GLOBAL_OFFSET_TABLE_@got(11) 60 # the linker thought GOT were ... 61 subf 9,10,11 # r9 = displacement 62 63 lwz 8,_GOT_END_@got(11) 64 add 8,8,9 # add the displacement 65 66 1: lwz 3,0(11) 67 add 3,3,9 # add the displacement 68 stw 3,0(11) 69 addi 11,11,4 # r11++ 70 cmpl 0,11,8 # done? 71 blt 1b 72 73 lwz 4,16(1) 74 addi 3,4,-12 # sp = &argv[-3] /* XXX */ 75 76 bl _rtld@plt # _start = _rtld(sp) 77 mtlr 3 78 79 lwz 3,12(1) # argc 80 lwz 4,16(1) # argv 81 lwz 5,20(1) # envp 82 lwz 6,-8(4) # obj = sp[1] (== argv[-2]) 83 lwz 7,-12(4) # cleanup = sp[0] (== argv[-3]) 84 lwz 8,32(1) # ps_strings 85 86 addi 1,1,48 87 blrl # _start(argc, argv, envp, obj, cleanup, ps_strings) 88 89 li 0,1 # _exit() 90 sc 91 92 93 .globl _rtld_bind_start 94 .globl _rtld_bind_powerpc 95 96 _rtld_bind_start: 97 stwu 1,-160(1) 98 99 stw 0,20(1) 100 mflr 0 101 stw 0,16(1) # save lr 102 mfcr 0 103 stw 0,12(1) # save cr 104 stmw 3,24(1) # save r3-r31 105 106 mr 3,12 # obj 107 mr 4,11 # reloff 108 bl _rtld_bind_powerpc@plt # _rtld_bind(obj, reloff) 109 mtctr 3 110 111 lmw 3,24(1) # load r3-r31 112 lwz 0,12(1) # restore cr 113 mtcr 0 114 lwz 0,16(1) # restore lr 115 mtlr 0 116 lwz 0,20(1) 117 118 addi 1,1,160 119 bctr 120 121 .globl _rtld_powerpc_pltcall 122 .globl _rtld_powerpc_pltresolve 123 124 _rtld_powerpc_pltcall: 125 slwi 11,11,2 126 addis 11,11,0 # addis 11,11,jmptab@ha 127 lwz 11,0(11) # lwz 11,jmptab@l(11) 128 mtctr 11 129 bctr 130 131 _rtld_powerpc_pltresolve: 132 lis 12,0 # lis 12,_rtld_bind_start@ha 133 addi 12,12,0 # addi 12,12,_rtld_bind_start@l 134 mtctr 12 135 lis 12,0 # lis 12,obj@ha 136 addi 12,12,0 # addi 12,12,obj@l 137 bctr 138
Indexes created Mon Sep 29 21:09:56 GMT 2025