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@@ -0,0 +1,124 @@
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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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+
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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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+
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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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+
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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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+ exception.
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+
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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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+
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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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+
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+
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+#include <features.h>
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+#include <sys/regdef.h>
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+
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+
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+
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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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+
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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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+
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+ sp ($29) The stack contains the arguments and environment:
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+ 0(%esp) argc
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+ 4(%esp) argv[0]
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+ ...
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+ (4*argc)(%esp) NULL
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+ (4*(argc+1))(%esp) envp[0]
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+ ...
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+ NULL
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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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+ stack frame.
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+*/
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+
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+
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+/* We need to call:
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+ __uClibc_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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+*/
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+
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+.text
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+ .global _start
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+ .type _start,%function
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+ .type _init,%function
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+ .type _fini,%function
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+ .type main,%function
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+ .type __uClibc_start_main,%function
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+
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+__start:
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+#ifdef __PIC__
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+ .set noreorder
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+ move $0, $31 /* Save old ra. */
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+ bal 10f /* Find addr of cpload. */
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+ nop
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+10:
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+ .cpload $31;
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+ move $31, $0;
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+ .set reorder
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+#else
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+ la $28, _gp /* Setup GP correctly if we're non-PIC. */
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+ move $31, $0
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+#endif
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+
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+
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+ la $4, main /* main */
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+ lw $5, 0($29) /* argc */
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+ addiu $6, $29, 4 /* argv */
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+
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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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+ and $29, -2 * 4
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+ subu $29, 32
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+ la $7, _init /* init */
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+ la $8, _fini
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+ sw $8, 16($29) /* fini */
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+ sw $2, 20($29) /* rtld_fini */
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+ sw $29, 24($29) /* stack_end */
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+ jal __uClibc_start_main
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+hlt:
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+ /* Crash if somehow `__uClibc_start_main' returns anyway. */
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+ b hlt
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+
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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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+
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+
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Eric Andersen