1/* Special support for trampolines 2 * 3 * Copyright (C) 1996, 1997, 2000 Free Software Foundation, Inc. 4 * Written By Michael Meissner 5 * 6 * This file is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License as published by the 8 * Free Software Foundation; either version 2, or (at your option) any 9 * later version. 10 * 11 * In addition to the permissions in the GNU General Public License, the 12 * Free Software Foundation gives you unlimited permission to link the 13 * compiled version of this file with other programs, and to distribute 14 * those programs without any restriction coming from the use of this 15 * file. (The General Public License restrictions do apply in other 16 * respects; for example, they cover modification of the file, and 17 * distribution when not linked into another program.) 18 * 19 * This file is distributed in the hope that it will be useful, but 20 * WITHOUT ANY WARRANTY; without even the implied warranty of 21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 22 * General Public License for more details. 23 * 24 * You should have received a copy of the GNU General Public License 25 * along with this program; see the file COPYING. If not, write to 26 * the Free Software Foundation, 51 Franklin Street, Fifth Floor, 27 * Boston, MA 02110-1301, USA. 28 * 29 * As a special exception, if you link this library with files 30 * compiled with GCC to produce an executable, this does not cause 31 * the resulting executable to be covered by the GNU General Public License. 32 * This exception does not however invalidate any other reasons why 33 * the executable file might be covered by the GNU General Public License. 34 */ 35 36/* Set up trampolines. */ 37 38 .file "tramp.asm" 39 .section ".text" 40 #include "ppc-asm.h" 41 42#ifndef __powerpc64__ 43 .type trampoline_initial,@object 44 .align 2 45trampoline_initial: 46 mflr r0 47 bcl 20,31,1f 48.Lfunc = .-trampoline_initial 49 .long 0 /* will be replaced with function address */ 50.Lchain = .-trampoline_initial 51 .long 0 /* will be replaced with static chain */ 521: mflr r11 53 mtlr r0 54 lwz r0,0(r11) /* function address */ 55 lwz r11,4(r11) /* static chain */ 56 mtctr r0 57 bctr 58 59trampoline_size = .-trampoline_initial 60 .size trampoline_initial,trampoline_size 61 62 63/* R3 = stack address to store trampoline */ 64/* R4 = length of trampoline area */ 65/* R5 = function address */ 66/* R6 = static chain */ 67 68FUNC_START(__trampoline_setup) 69 mflr r0 /* save return address */ 70 bcl 20,31,.LCF0 /* load up __trampoline_initial into r7 */ 71.LCF0: 72 mflr r11 73 addi r7,r11,trampoline_initial-4-.LCF0 /* trampoline address -4 */ 74 75 li r8,trampoline_size /* verify that the trampoline is big enough */ 76 cmpw cr1,r8,r4 77 srwi r4,r4,2 /* # words to move */ 78 addi r9,r3,-4 /* adjust pointer for lwzu */ 79 mtctr r4 80 blt cr1,.Labort 81 82 mtlr r0 83 84 /* Copy the instructions to the stack */ 85.Lmove: 86 lwzu r10,4(r7) 87 stwu r10,4(r9) 88 bdnz .Lmove 89 90 /* Store correct function and static chain */ 91 stw r5,.Lfunc(r3) 92 stw r6,.Lchain(r3) 93 94 /* Now flush both caches */ 95 mtctr r4 96.Lcache: 97 icbi 0,r3 98 dcbf 0,r3 99 addi r3,r3,4 100 bdnz .Lcache 101 102 /* Finally synchronize things & return */ 103 sync 104 isync 105 blr 106 107.Labort: 108#if defined SHARED && defined HAVE_AS_REL16 109 bcl 20,31,1f 1101: mflr r30 111 addis r30,r30,_GLOBAL_OFFSET_TABLE_-1b@ha 112 addi r30,r30,_GLOBAL_OFFSET_TABLE_-1b@l 113#endif 114 bl JUMP_TARGET(abort) 115FUNC_END(__trampoline_setup) 116 117#endif 118 119 .section .note.GNU-stack,"",%progbits 120