glibc/sysdeps/hppa/start.S
John David Anglin 9765ffa710 hppa: fix loading of global pointer in _start [BZ #20277]
The patched change fixes a regression for executables compiled with the
-p option and linked with gcrt1.o.  The executables crash on startup.

This regression was introduced in 2.22 and was noticed in the gcc testsuite.
2016-06-30 11:37:08 -04:00

158 lines
4.4 KiB
ArmAsm

/* ELF startup code for HPPA.
Copyright (C) 2002-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
In addition to the permissions in the GNU Lesser 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 GNU Lesser 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.)
Note that people who make modified versions of this file are not
obligated to grant this special exception for their modified
versions; it is their choice whether to do so. The GNU Lesser
General Public License gives permission to release a modified
version without this exception; this exception also makes it
possible to release a modified version which carries forward this
exception.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<http://www.gnu.org/licenses/>. */
.import main, code
.import $global$, data
.import __libc_start_main, code
.import __libc_csu_fini, code
.import __libc_csu_init, code
/* Have the linker create plabel words so we get PLABEL32
relocs and not 21/14. The use of 21/14 relocs is only
supported in the latest dynamic linker. */
#ifdef SHARED
.section .data.rel.ro,"aw",@progbits
#else
.section .rodata,"a",@progbits
#endif
.align 4
.Lpmain:
.word P%main
.Lp__libc_start_main:
.word P%__libc_start_main
.Lp__libc_csu_fini:
.word P%__libc_csu_fini
.Lp__libc_csu_init:
.word P%__libc_csu_init
#ifdef SHARED
.Lp__global:
.word $global$
#endif
.text
.align 4
.globl _start
.export _start, ENTRY
.type _start,@function
_start:
/* At entry to the function we have:
r26 - Unused
r25 - argc
r24 - argv
r23 - False _dl_fini plabel address
This function is called from the lower half of RTLD_START.
The call to __libc_start_main expects:
1. r26 - Application main
2. r25 - argc
3. r24 - argv
4. r23 - __libc_csu_init
5. sp-52 - __libc_csu_fini
6. sp-56 - rtld_fini
7. sp-60 - stackend */
.proc
.callinfo
/* Clear previous-sp. */
stw %r0, -4(%sp)
/* Setup the stack and frame. */
stw %rp, -20(%sp)
ldo 64(%sp), %sp
stw %sp, -4(%sp)
stw %r19, -32(%sp)
/* argc and argv should be in 25 and 24 (2nd and 3rd argument) */
/* void (*rtld_fini) (void) (6th argument) */
stw %r23, -56(%sp)
/* Need to setup 1, 4, 5, and 7th arguments */
#ifdef SHARED
/* load main (1st argument) */
addil LT'.Lpmain, %r19
ldw RT'.Lpmain(%r1), %r26
ldw 0(%r26),%r26
/* void (*init) (void) (4th argument) */
addil LT'.Lp__libc_csu_init, %r19
ldw RT'.Lp__libc_csu_init(%r1), %r23
ldw 0(%r23), %r23
/* void (*fini) (void) (5th argument) */
addil LT'.Lp__libc_csu_fini, %r19
ldw RT'.Lp__libc_csu_fini(%r1), %r22
ldw 0(%r22), %r22
#else
/* load main (1st argument) */
ldil LR'.Lpmain, %r26
ldw RR'.Lpmain(%r26), %r26
/* void (*init) (void) (4th argument) */
ldil LR'.Lp__libc_csu_init, %r23
ldw RR'.Lp__libc_csu_init(%r23), %r23
/* void (*fini) (void) (5th argument) */
ldil LR'.Lp__libc_csu_fini, %r22
ldw RR'.Lp__libc_csu_fini(%r22), %r22
#endif
/* Store 5th argument */
stw %r22, -52(%sp)
/* void *stack_end (7th argument) */
stw %sp, -60(%sp)
#ifdef SHARED
/* load global */
addil LT'.Lp__global, %r19
ldw RT'.Lp__global(%r1), %dp
ldw 0(%dp), %dp
#else
/* load global */
ldil L%$global$, %dp
ldo R%$global$(%dp), %dp
#endif
bl __libc_start_main,%r2
nop
/* die horribly if it returned (it shouldn't) */
iitlbp %r0,(%sr0,%r0)
nop
.procend
/* Define a symbol for the first piece of initialized data. */
.data
.globl __data_start
__data_start:
.long 0
.weak data_start
data_start = __data_start