glibc/sysdeps/i386/elf/start.S
Roland McGrath 06b31ad3ef * elf/Makefile (tests): Uncomment tst-array[123].
* Makeconfig (CPPFLAGS-.oS): Add -DLIBC_NONSHARED=1.
	* csu/elf-init.c: New file.
	* csu/Makefile (routines, static-only-routines): Add elf-init.
	* sysdeps/alpha/elf/start.S: Use __libc_csu_init in place of _init
	and __libc_csu_fini in place of _fini.
	* sysdeps/arm/elf/start.S: Likewise.
	* sysdeps/cris/elf/start.S: Likewise.
	* sysdeps/hppa/elf/start.S: Likewise.
	* sysdeps/i386/elf/start.S: Likewise.
	* sysdeps/ia64/elf/start.S: Likewise.
	* sysdeps/m68k/elf/start.S: Likewise.
	* sysdeps/mach/hurd/powerpc/static-start.S: Likewise.
	* sysdeps/mips/elf/start.S: Likewise.
	* sysdeps/powerpc/powerpc32/elf/start.S: Likewise.
	* sysdeps/powerpc/powerpc64/elf/start.S: Likewise.
	* sysdeps/s390/s390-32/elf/start.S: Likewise.
	* sysdeps/s390/s390-64/elf/start.S: Likewise.
	* sysdeps/sh/elf/start.S: Likewise.
	* sysdeps/sparc/sparc32/elf/start.S: Likewise.
	* sysdeps/sparc/sparc64/elf/start.S: Likewise.
	* sysdeps/x86_64/elf/start.S: Likewise.
2002-12-09 20:37:37 +00:00

100 lines
3.2 KiB
ArmAsm

/* Startup code compliant to the ELF i386 ABI.
Copyright (C) 1995,1996,1997,1998,2000,2001, 2002 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.
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. */
/* This is the canonical entry point, usually the first thing in the text
segment. The SVR4/i386 ABI (pages 3-31, 3-32) says that when the entry
point runs, most registers' values are unspecified, except for:
%edx Contains a function pointer to be registered with `atexit'.
This is how the dynamic linker arranges to have DT_FINI
functions called for shared libraries that have been loaded
before this code runs.
%esp The stack contains the arguments and environment:
0(%esp) argc
4(%esp) argv[0]
...
(4*argc)(%esp) NULL
(4*(argc+1))(%esp) envp[0]
...
NULL
*/
#include "bp-sym.h"
.text
.globl _start
.type _start,@function
_start:
/* Clear the frame pointer. The ABI suggests this be done, to mark
the outermost frame obviously. */
xorl %ebp, %ebp
/* Extract the arguments as encoded on the stack and set up
the arguments for `main': argc, argv. envp will be determined
later in __libc_start_main. */
popl %esi /* Pop the argument count. */
movl %esp, %ecx /* argv starts just at the current stack top.*/
/* Before pushing the arguments align the stack to a 16-byte
(SSE needs 16-byte alignment) boundary to avoid penalties from
misaligned accesses. Thanks to Edward Seidl <seidl@janed.com>
for pointing this out. */
andl $0xfffffff0, %esp
pushl %eax /* Push garbage because we allocate
28 more bytes. */
/* Provide the highest stack address to the user code (for stacks
which grow downwards). */
pushl %esp
pushl %edx /* Push address of the shared library
termination function. */
/* Push address of our own entry points to .fini and .init. */
pushl $__libc_csu_fini
pushl $__libc_csu_init
pushl %ecx /* Push second argument: argv. */
pushl %esi /* Push first argument: argc. */
pushl $BP_SYM (main)
/* Call the user's main function, and exit with its value.
But let the libc call main. */
call BP_SYM (__libc_start_main)
hlt /* Crash if somehow `exit' does return. */
/* To fulfill the System V/i386 ABI we need this symbol. Yuck, it's so
meaningless since we don't support machines < 80386. */
.section .rodata
.globl _fp_hw
_fp_hw: .long 3
.size _fp_hw, 4
.type _fp_hw,@object
/* 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