NetBSD/libexec/ld.aout_so/arch/arm32/mdprologue.S

93 lines
3.1 KiB
ArmAsm
Raw Normal View History

/* $NetBSD: mdprologue.S,v 1.1 1997/10/17 21:25:59 mark Exp $ */
/*
* Copyright (C) 1996 Wolfgang Solfrank
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Wolfgang Solfrank.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* arm run-time link editor entry points.
*/
#include <machine/asm.h>
#include <sys/syscall.h>
.text
/*
* _rtl(int version, struct crt_ldso *crtp)
*/
.align 0
.type _rtl,#function
_rtl: @ crt0 calls us here
mov ip, sp @ Allocate stack frame
stmfd sp!, {sl, fp, ip, lr, pc}
sub fp, ip, #4
ldr r3, [r1, #0] @ base address of ld.so (first field)
@ setup arguments for rtld()
ldr sl, GOTaddr @ get pc-rel offset for GOT
add sl, pc, sl @ here is the GOT
L1:
ldr r2, DYNAMICaddr
ldr r2, [sl, r2] @ 1st entry in GOT is our __DYNAMIC
add r2, r2, r3 @ add load address
ldr lr, rtldaddr @ get GOT offset for function
ldr lr, [sl, lr] @ get function address
add r3, lr, r3 @ and relocate
mov lr, pc
mov pc, r3 @ _rtld(version, crtp, DYNAMIC)
ldmea fp, {sl, fp, ip, pc}
.align 0
GOTaddr:
.word __GLOBAL_OFFSET_TABLE_ + (. - (L1+4) )
DYNAMICaddr:
.word __DYNAMIC
rtldaddr:
.word _rtld
@ First call to a procedure generally comes through here for
@ binding.
ENTRY(binder_entry)
stmfd sp!, {r0-fp, ip, lr, pc} @ save all regs in standard frame
@ (ip and lr to be fixed later)
add fp, sp, #(15-1)*4 @ get new fp
add r0, fp, #4 @ compute old sp
str r0, [fp, #-8] @ fixup saved ip
sub r0, ip, #(8+12) @ make it point to the jmpslot
bl _binder
str r0, [fp] @ return value from _binder()
@ == actual address of function
ldmfa fp, {r0-fp, sp, lr, pc} @ restore regs