gcc-papermario/config/rs6000/tramp.asm
2020-09-20 21:06:00 -04:00

121 lines
3.4 KiB
NASM

/* 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 */