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/* Startup code compliant to the ELF Mips ABI.
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Copyright (C) 1995, 1997, 2000, 2001, 2002, 2003, 2004
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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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In addition to the permissions in the GNU Lesser General Public
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License, the Free Software Foundation gives you unlimited
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permission to link the compiled version of this file with other
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programs, and to distribute those programs without any restriction
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coming from the use of this file. (The GNU Lesser General Public
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License restrictions do apply in other respects; for example, they
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cover modification of the file, and distribution when not linked
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into another program.)
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Note that people who make modified versions of this file are not
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obligated to grant this special exception for their modified
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versions; it is their choice whether to do so. The GNU Lesser
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General Public License gives permission to release a modified
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version without this exception; this exception also makes it
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possible to release a modified version which carries forward this
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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, see
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<http://www.gnu.org/licenses/>. */
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#define __ASSEMBLY__ 1
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#error ENTRY_POINT needs to be defined for start.S on MIPS/ELF.
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/* This is the canonical entry point, usually the first thing in the text
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segment. The SVR4/Mips ABI (pages 3-31, 3-32) says that when the entry
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point runs, most registers' values are unspecified, except for:
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v0 ($2) 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 ($29) The stack contains the arguments and environment:
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(4*(argc+1))(%esp) envp[0]
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ra ($31) The return address register is set to zero so that programs
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that search backword through stack frames recognize the last
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__libc_start_main (int (*main) (int, char **, char **), int argc,
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char **argv, void (*init) (void), void (*fini) (void),
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void (*rtld_fini) (void), void *stack_end)
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.type ENTRY_POINT,@function
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PTR_LA $28, _gp /* Setup GP correctly if we're non-PIC. */
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PTR_LA $4, main /* main */
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PTR_L $5, 0($29) /* argc */
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PTR_ADDIU $6, $29, PTRSIZE /* argv */
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/* Allocate space on the stack for seven arguments (o32 only)
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and make sure the stack is aligned to double words (8 bytes)
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on o32 and quad words (16 bytes) on n32 and n64. */
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#if _MIPS_SIM == _ABIO32
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PTR_LA $7, __libc_csu_init /* init */
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PTR_LA $8, __libc_csu_fini
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#if _MIPS_SIM == _ABIO32
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PTR_S $8, 16($29) /* fini */
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PTR_S $2, 20($29) /* rtld_fini */
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PTR_S $29, 24($29) /* stack_end */
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move $9, $2 /* rtld_fini */
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move $10, $29 /* stack_end */
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jal __libc_start_main
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hlt: b hlt /* Crash if somehow it does return. */
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/* Define a symbol for the first piece of initialized data. */
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data_start = __data_start