git://gcc.gnu.org / gcc.git / blame
| Commit | Line | Data |
|---|---|---|
| a0d66c8d | 1 | /* Special support for trampolines |
| eaf1bcf1 | 2 | * |
| a0d66c8d | 3 | * Copyright (C) 1996, 1997 Free Software Foundation, Inc. |
| eaf1bcf1 MM |
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, 59 Temple Place - Suite 330, | |
| 27 | * Boston, MA 02111-1307, 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 | .globl __trampoline_initial | |
| 43 | .type __trampoline_initial,@object | |
| 44 | .align 2 | |
| 45 | __trampoline_initial: | |
| 46 | mflr r0 | |
| 47 | bl 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 */ | |
| 52 | 1: 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 | ||
| 59 | __trampoline_size = .-__trampoline_initial | |
| 60 | .size __trampoline_initial,__trampoline_size | |
| 61 | ||
| 62 | .section ".got2","aw" | |
| 63 | .LCTOC1 = .+32768 | |
| 64 | .Ltramp = .-.LCTOC1 | |
| 65 | .long __trampoline_initial-4 | |
| 66 | ||
| 67 | .section ".text" | |
| 68 | .LCL0: | |
| 69 | .long .LCTOC1-.LCF0 | |
| 70 | ||
| 71 | /* R3 = stack address to store trampoline */ | |
| 72 | /* R4 = length of trampoline area */ | |
| 73 | /* R5 = function address */ | |
| 74 | /* R6 = static chain */ | |
| 75 | ||
| 76 | FUNC_START(__trampoline_setup) | |
| 77 | mflr r0 /* save return address */ | |
| 78 | bl .LCF0 /* load up __trampoline_initial into r7 */ | |
| 79 | .LCF0: | |
| 80 | mflr r11 | |
| 81 | lwz r12,(.LCL0-.LCF0)(r11) | |
| 82 | add r11,r12,r11 | |
| a0d66c8d | 83 | lwz r7,.Ltramp(r11) /* trampoline address -4 */ |
| eaf1bcf1 MM |
84 | |
| 85 | li r8,__trampoline_size /* verify that the trampoline is big enough */ | |
| 86 | cmpw cr1,r8,r4 | |
| 87 | srwi r4,r4,2 /* # words to move */ | |
| 88 | addi r9,r3,-4 /* adjust pointer for lwzu */ | |
| 89 | mtctr r4 | |
| 90 | blt cr1,.Labort | |
| 91 | ||
| 92 | mtlr r0 | |
| 93 | ||
| 94 | /* Copy the instructions to the stack */ | |
| 95 | .Lmove: | |
| 96 | lwzu r10,4(r7) | |
| 97 | stwu r10,4(r9) | |
| 98 | bdnz .Lmove | |
| 99 | ||
| 100 | /* Store correct function and static chain */ | |
| 101 | stw r5,.Lfunc(r3) | |
| 102 | stw r6,.Lchain(r3) | |
| 103 | ||
| 104 | /* Now flush both caches */ | |
| 105 | mtctr r4 | |
| 106 | .Lcache: | |
| 107 | icbi 0,r3 | |
| 108 | dcbf 0,r3 | |
| 109 | addi r3,r3,4 | |
| 110 | bdnz .Lcache | |
| 111 | ||
| 112 | /* Finally synchronize things & return */ | |
| 113 | sync | |
| 114 | isync | |
| 115 | blr | |
| 116 | ||
| 117 | .Labort: | |
| 118 | bl abort | |
| 119 | FUNC_END(__trampoline_setup) | |
| 120 | /* END CYGNUS LOCAL -- waiting for FSF sources to be restored/meissner */ |