/* Special support for trampolines * * Copyright (C) 1996, 1997 Free Software Foundation, Inc. * Written By Michael Meissner * * This file is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2, or (at your option) any * later version. * * In addition to the permissions in the GNU General Public License, the * Free Software Foundation gives you unlimited permission to link the * compiled version of this file with other programs, and to distribute * those programs without any restriction coming from the use of this * file. (The General Public License restrictions do apply in other * respects; for example, they cover modification of the file, and * distribution when not linked into another program.) * * This file is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; see the file COPYING. If not, write to * the Free Software Foundation, 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. * * As a special exception, if you link this library with files * compiled with GCC to produce an executable, this does not cause * the resulting executable to be covered by the GNU General Public License. * This exception does not however invalidate any other reasons why * the executable file might be covered by the GNU General Public License. */ /* Set up trampolines */ .file "tramp.asm" .section ".text" #include "ppc-asm.h" .globl __trampoline_initial .type __trampoline_initial,@object .align 2 __trampoline_initial: mflr r0 bl 1f .Lfunc = .-__trampoline_initial .long 0 /* will be replaced with function address */ .Lchain = .-__trampoline_initial .long 0 /* will be replaced with static chain */ 1: mflr r11 mtlr r0 lwz r0,0(r11) /* function address */ lwz r11,4(r11) /* static chain */ mtctr r0 bctr __trampoline_size = .-__trampoline_initial .size __trampoline_initial,__trampoline_size .section ".got2","aw" .LCTOC1 = .+32768 .Ltramp = .-.LCTOC1 .long __trampoline_initial-4 .section ".text" .LCL0: .long .LCTOC1-.LCF0 /* R3 = stack address to store trampoline */ /* R4 = length of trampoline area */ /* R5 = function address */ /* R6 = static chain */ FUNC_START(__trampoline_setup) mflr r0 /* save return address */ bl .LCF0 /* load up __trampoline_initial into r7 */ .LCF0: mflr r11 lwz r12,(.LCL0-.LCF0)(r11) add r11,r12,r11 lwz r7,.Ltramp(r11) /* trampoline address -4 */ li r8,__trampoline_size /* verify that the trampoline is big enough */ cmpw cr1,r8,r4 srwi r4,r4,2 /* # words to move */ addi r9,r3,-4 /* adjust pointer for lwzu */ mtctr r4 blt cr1,.Labort mtlr r0 /* Copy the instructions to the stack */ .Lmove: lwzu r10,4(r7) stwu r10,4(r9) bdnz .Lmove /* Store correct function and static chain */ stw r5,.Lfunc(r3) stw r6,.Lchain(r3) /* Now flush both caches */ mtctr r4 .Lcache: icbi 0,r3 dcbf 0,r3 addi r3,r3,4 bdnz .Lcache /* Finally synchronize things & return */ sync isync blr .Labort: bl abort FUNC_END(__trampoline_setup) /* END CYGNUS LOCAL -- waiting for FSF sources to be restored/meissner */