86 lines
2.4 KiB
ArmAsm
86 lines
2.4 KiB
ArmAsm
/* Startup code for ARM & ELF
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Copyright (C) 1995, 1996, 1997, 1998, 2001, 2002 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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/* This is the canonical entry point, usually the first thing in the text
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segment.
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Note that the code in the .init section has already been run.
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This includes _init and _libc_init
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At this entry point, most registers' values are unspecified, except:
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a1 Contains a function pointer to be registered with `atexit'.
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This is how the dynamic linker arranges to have DT_FINI
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functions called for shared libraries that have been loaded
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before this code runs.
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sp The stack contains the arguments and environment:
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0(sp) argc
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4(sp) argv[0]
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...
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(4*argc)(sp) NULL
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(4*(argc+1))(sp) envp[0]
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...
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NULL
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*/
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.text
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.globl _start
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.type _start,#function
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_start:
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/* Fetch address of fini */
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ldr ip, =__libc_csu_fini
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/* Clear the frame pointer since this is the outermost frame. */
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mov fp, #0
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/* Pop argc off the stack and save a pointer to argv */
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ldr a2, [sp], #4
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mov a3, sp
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/* Push stack limit */
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str a3, [sp, #-4]!
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/* Push rtld_fini */
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str a1, [sp, #-4]!
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/* Set up the other arguments in registers */
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ldr a1, =main
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ldr a4, =__libc_csu_init
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/* Push fini */
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str ip, [sp, #-4]!
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/* __libc_start_main (main, argc, argv, init, fini, rtld_fini, stack_end) */
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/* Let the libc call main and exit with its return code. */
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bl __libc_start_main
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/* should never get here....*/
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bl abort
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/* Define a symbol for the first piece of initialized data. */
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.data
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.globl __data_start
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__data_start:
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.long 0
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.weak data_start
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data_start = __data_start
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