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+/* Startup code for ARM & ELF
+ Copyright (C) 1995, 1996, 1997, 1998 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 Library General Public License as
+ published by the Free Software Foundation; either version 2 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
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public
+ License along with the GNU C Library; see the file COPYING.LIB. 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.
+
+ Note that the code in the .init section has already been run.
+ This includes _init and _libc_init
+
+
+ At this entry point, most registers' values are unspecified, except for:
+
+ r0 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.
+
+ sp 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
+*/
+
+ .text
+ .globl _start
+_start:
+ /* Clear the frame pointer. The Intel ABI suggests this be done,
+ to mark the outermost frame obviously. This seems like a
+ sensible thing to do */
+ mov fp, #0
+
+ /* r0 contains the address of the shared library termination
+ function, which we will register with `atexit' to be called by
+ `exit'. I suspect that on some systems, and when statically
+ linked, this will not be set by anything to any function
+ pointer; hopefully it will be zero so we don't try to call
+ random pointers. */
+ cmp r0,#0
+ blne atexit(PLT)
+
+ /* Do essential libc initialization. In statically linked
+ programs under the GNU Hurd, this is what sets up the
+ arguments on the stack for the code below. For dyn-link
+ programs, this has been run already, in the .init code. */
+#ifndef PIC
+ bl __libc_init_first
+
+ /* Extract the arguments and environment as encoded on the stack
+ and set up the arguments for `main': argc, argv, envp. */
+ ldr r0,[sp]
+ add r1,sp,#4
+ add r2,r1,r0,lsl #2
+ add r2,r2,#4
+ /* save a copy of envp while we have it */
+ ldr r3,L_environ
+ str r2,[r3]
+
+ /* Call `_init', which is the entry point to our own `.init'
+ section; and register with `atexit' to have `exit' call
+ `_fini', which is the entry point to our own `.fini' section. */
+ bl _init
+ ldr r0,L_fini
+ bl atexit
+ b L_pfini
+
+L_fini: .word _fini
+L_environ: .word _environ
+L_pfini:
+#endif
+ /* rebuild the arg list for main() */
+ ldr r0,[sp]
+ add r1,sp,#4
+ add r2,r1,r0,lsl #2
+ add r2,r2,#4
+
+ /* Call the user's main function, and exit with its value. */
+ bl main
+ bl exit
+ /* should never get here....*/
+ bl abort
+
+
+/* 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