mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-27 04:41:02 +08:00
115 lines
3.2 KiB
ArmAsm
115 lines
3.2 KiB
ArmAsm
/* Copyright (C) 2011 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
|
|
|
|
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.
|
|
|
|
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, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
|
02111-1307 USA. */
|
|
|
|
#include <sysdep.h>
|
|
|
|
/* Get address of "sym" in "reg" assuming r51 holds ".Llink". */
|
|
.macro pic_addr reg, sym
|
|
#ifdef __tilegx__
|
|
moveli \reg, hw1_last(\sym - .Llink)
|
|
shl16insli \reg, \reg, hw0(\sym - .Llink)
|
|
ADD_PTR \reg, r51, \reg
|
|
#else
|
|
ADDLI_PTR \reg, r51, lo16(\sym - .Llink)
|
|
auli \reg, \reg, ha16(\sym - .Llink)
|
|
#endif
|
|
.endm
|
|
|
|
.text
|
|
ENTRY (_start)
|
|
/* Linux starts us with sp pointing at the conventional Elf layout,
|
|
but we need to allow two 'caller' words for our ABI convention. */
|
|
{
|
|
move r52, sp
|
|
andi sp, sp, -8
|
|
}
|
|
cfi_def_cfa_register (r52)
|
|
{
|
|
/* Point sp at base of ABI area; point r4 to the caller-sp word. */
|
|
ADDI_PTR sp, sp, -(2 * REGSIZE)
|
|
ADDI_PTR r4, sp, -REGSIZE
|
|
}
|
|
{
|
|
/* Save zero for caller sp in our 'caller' save area, and make
|
|
sure lr has a zero value, to limit backtraces. */
|
|
move lr, zero
|
|
ST r4, zero
|
|
}
|
|
{
|
|
move r0, r52
|
|
jal _dl_start
|
|
}
|
|
/* Save returned start of user program address for later. */
|
|
move r50, r0
|
|
|
|
/* See if we were invoked explicitly with the dynamic loader,
|
|
in which case we have to adjust the argument vector. */
|
|
lnk r51; .Llink:
|
|
pic_addr r4, _dl_skip_args
|
|
LD4U r4, r4
|
|
BEQZT r4, .Lno_skip
|
|
|
|
/* Load the argc word at the initial sp and adjust it.
|
|
We basically jump "sp" up over the first few argv entries
|
|
and write "argc" a little higher up in memory, to be the
|
|
base of the new kernel-initialized stack area. */
|
|
LD_PTR r0, r52
|
|
{
|
|
sub r0, r0, r4
|
|
SHL_PTR_ADD r52, r4, r52
|
|
}
|
|
{
|
|
ST_PTR r52, r0
|
|
SHL_PTR_ADD sp, r4, sp
|
|
}
|
|
|
|
.Lno_skip:
|
|
/* Call_dl_init (_dl_loaded, argc, argv, envp). See elf/start.s
|
|
for the layout of memory here; r52 is pointing to "+0". */
|
|
pic_addr r0, _rtld_local
|
|
{
|
|
LD_PTR r1, r52 /* load argc in r1 */
|
|
ADDLI_PTR r2, r52, __SIZEOF_POINTER__ /* point r2 at argv */
|
|
}
|
|
{
|
|
LD_PTR r0, r0 /* yields _rtld_global._ns_loaded */
|
|
addi r3, r1, 1
|
|
move lr, zero
|
|
}
|
|
{
|
|
SHL_PTR_ADD r3, r3, r2 /* point r3 at envp */
|
|
jal _dl_init_internal
|
|
}
|
|
|
|
/* Call user program whose address we saved in r50.
|
|
We invoke it just like a static binary, but with _dl_fini
|
|
in r0 so we can distinguish. */
|
|
|
|
pic_addr r0, _dl_fini
|
|
move lr, zero
|
|
{
|
|
move sp, r52
|
|
jr r50
|
|
}
|
|
|
|
/* Tell backtracer to give up (_start has no caller). */
|
|
info 2 /* INFO_OP_CANNOT_BACKTRACE */
|
|
|
|
END (_start)
|