rtld_start.S revision 1.2
1 /* $NetBSD: rtld_start.S,v 1.2 1999/04/18 19:40:07 ws 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 addi 11,3,4 # r11 = (real) GOT 54 lwz 10,_GLOBAL_OFFSET_TABLE_@got(11) 55 # the linker thought GOT were ... 56 subf 9,10,11 # r9 = displacement 57 58 lwz 8,_GOT_END_@got(11) 59 add 8,8,9 # add the displacement 60 61 1: lwz 3,0(11) 62 add 3,3,9 # add the displacement 63 stw 3,0(11) 64 addi 11,11,4 # r11++ 65 cmpl 0,11,8 # done? 66 blt 1b 67 68 lwz 4,16(1) 69 addi 3,4,-12 # sp = &argv[-3] /* XXX */ 70 71 bl _rtld@plt # _start = _rtld(sp) 72 mtlr 3 73 74 lwz 3,12(1) # argc 75 lwz 4,16(1) # argv 76 lwz 5,20(1) # envp 77 lwz 6,-8(4) # obj = sp[1] (== argv[-2]) 78 lwz 7,-12(4) # cleanup = sp[0] (== argv[-3]) 79 lwz 8,32(1) # ps_strings 80 81 addi 1,1,48 82 blrl # _start(argc, argv, envp, obj, cleanup, ps_strings) 83 84 li 0,1 # _exit() 85 sc 86 87 88 .globl _rtld_bind_start 89 .globl _rtld_bind_powerpc 90 91 _rtld_bind_start: 92 stwu 1,-160(1) 93 stw 0,20(1) 94 mflr 0 95 stw 0,16(1) # save lr 96 stmw 3,24(1) # save r3-r31 97 98 mr 3,12 # obj 99 mr 4,11 # reloff 100 bl _rtld_bind_powerpc@plt # _rtld_bind(obj, reloff) 101 mtctr 3 102 103 lwz 0,16(1) # restore lr 104 mtlr 0 105 lwz 0,20(1) 106 lmw 3,24(1) # load r3-r31 107 addi 1,1,160 108 bctr 109 110 .globl _rtld_powerpc_pltcall 111 .globl _rtld_powerpc_pltresolve 112 113 _rtld_powerpc_pltcall: 114 slwi 11,11,2 115 addis 11,11,0 # addis 11,11,jmptab@ha 116 lwz 11,0(11) # lwz 11,jmptab@l(11) 117 mtctr 11 118 bctr 119 120 _rtld_powerpc_pltresolve: 121 lis 12,0 # lis 12,_rtld_bind_start@ha 122 addi 12,12,0 # addi 12,12,_rtld_bind_start@l 123 mtctr 12 124 lis 12,0 # lis 12,obj@ha 125 addi 12,12,0 # addi 12,12,obj@l 126 bctr 127
Indexes created Tue Oct 14 01:09:49 GMT 2025