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authorEric Andersen <andersen@codepoet.org>2005-05-27 00:23:45 +0000
committerEric Andersen <andersen@codepoet.org>2005-05-27 00:23:45 +0000
commit00422f5696652c04b919d6984adb2cdc21fd6955 (patch)
tree3cfd69e809fc3d9ee6e82652535382cb7134ffa2 /libc/sysdeps/linux/mips/crt1.S
parentabf812568a177684a3c14bcf76d5b379a38b1b6d (diff)
With a bit of luck, this might just get mips working again
Diffstat (limited to 'libc/sysdeps/linux/mips/crt1.S')
-rw-r--r--libc/sysdeps/linux/mips/crt1.S124
1 files changed, 124 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/mips/crt1.S b/libc/sysdeps/linux/mips/crt1.S
new file mode 100644
index 000000000..b9a206e01
--- /dev/null
+++ b/libc/sysdeps/linux/mips/crt1.S
@@ -0,0 +1,124 @@
+/* Startup code compliant to the ELF Mips ABI.
+ Copyright (C) 1995, 1997, 2000, 2001, 2002, 2003, 2004
+ 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.
+
+ In addition to the permissions in the GNU Lesser General Public
+ License, the Free Software Foundation gives you unlimited
+ permission to link the compiled version of this file with other
+ programs, and to distribute those programs without any restriction
+ coming from the use of this file. (The GNU Lesser General Public
+ License restrictions do apply in other respects; for example, they
+ cover modification of the file, and distribution when not linked
+ into another program.)
+
+ Note that people who make modified versions of this file are not
+ obligated to grant this special exception for their modified
+ versions; it is their choice whether to do so. The GNU Lesser
+ General Public License gives permission to release a modified
+ version without this exception; this exception also makes it
+ possible to release a modified version which carries forward this
+ exception.
+
+ 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. */
+
+
+#include <features.h>
+#include <sys/regdef.h>
+
+
+
+/* This is the canonical entry point, usually the first thing in the text
+ segment. The SVR4/Mips ABI (pages 3-31, 3-32) says that when the entry
+ point runs, most registers' values are unspecified, except for:
+
+ v0 ($2) 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 ($29) 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
+ ra ($31) The return address register is set to zero so that programs
+ that search backword through stack frames recognize the last
+ stack frame.
+*/
+
+
+/* We need to call:
+ __uClibc_start_main (int (*main) (int, char **, char **), int argc,
+ char **argv, void (*init) (void), void (*fini) (void),
+ void (*rtld_fini) (void), void *stack_end)
+*/
+
+.text
+ .global _start
+ .type _start,%function
+ .type _init,%function
+ .type _fini,%function
+ .type main,%function
+ .type __uClibc_start_main,%function
+
+__start:
+#ifdef __PIC__
+ .set noreorder
+ move $0, $31 /* Save old ra. */
+ bal 10f /* Find addr of cpload. */
+ nop
+10:
+ .cpload $31;
+ move $31, $0;
+ .set reorder
+#else
+ la $28, _gp /* Setup GP correctly if we're non-PIC. */
+ move $31, $0
+#endif
+
+
+ la $4, main /* main */
+ lw $5, 0($29) /* argc */
+ addiu $6, $29, 4 /* argv */
+
+ /* Allocate space on the stack for seven arguments (o32 only)
+ and make sure the stack is aligned to double words (8 bytes)
+ on o32 and quad words (16 bytes) on n32 and n64. */
+ and $29, -2 * 4
+ subu $29, 32
+ la $7, _init /* init */
+ la $8, _fini
+ sw $8, 16($29) /* fini */
+ sw $2, 20($29) /* rtld_fini */
+ sw $29, 24($29) /* stack_end */
+ jal __uClibc_start_main
+hlt:
+ /* Crash if somehow `__uClibc_start_main' returns anyway. */
+ b hlt
+
+/* 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
+
+