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[/] [or1k/] [trunk/] [linux/] [uClibc/] [libc/] [sysdeps/] [linux/] [sh/] [crt0.S] - Rev 1765

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/* Startup code for SH & ELF.
   Copyright (C) 1999 Free Software Foundation, Inc.
   Copyright (C) 2001 Hewlett-Packard Australia
   Copyright (C) 2002 Stefan Allius

 This program 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.

 This program 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 this program; 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.

        At this entry point, most registers' values are unspecified, except:

   sp           The stack contains the arguments and environment:
                0(sp)                   argc
                4(sp)                   argv[0]
                ...
                (4*argc)(sp)            NULL
                (4*(argc+1))(sp)        envp[0]
                ...
                                        NULL
*/

#include <features.h>

        .file "crt0.S"
        .text
        .globl _start
        .type _start,@function
        .type main,@function
        .size _start,_start_end - _start
_start:
        /* Clear the frame pointer since this is the outermost frame. */
        mov #0, r14

        /* Pop argc off the stack and save a pointer to argv */
        mov.l @r15+,r4
        mov r15, r5

#if defined L_crt0 || ! defined __UCLIBC_CTOR_DTOR__
        /*
         * Setup the value for the environment pointer:
         * r6 = (argc + 1) * 4
         * r6 += argv (in delay slot)
         */
        mov r4,r6
        add #1,r6
        shll2 r6

        /* jump to __uClibc_main (argc, argv, envp) */
        mov.l L_main, r0
        jsr @r0
        add r5, r6 /* delay slot */

        /* We should not get here. */
        mov.l L_abort, r0
        jmp @r0
        nop

_start_end:     
        .align  2

L_main:
        .long   __uClibc_main /* in libuClibc.*.so */

#else /* (L_crt1 || L_gcrt1) && __UCLIBC_CTOR_DTOR__ */
        /* Push the finip argument to __uClibc_start_main() onto the stack */
        mov.l L_fini,r6
        mov.l r6,@-r15

        /* Setup the value for the initp argument */
        mov.l L_init, r7

        /*
         * Setup the value for the environment pointer:
         * r6 = (argc + 1) * 4
         * r6 += argv (in delay slot)
         */
        mov r4,r6
        add #1,r6
        shll2 r6

        /* jump to __uClibc_start_main (argc, argv, envp, app_init, app_fini) */
        mov.l L_main, r0
        jsr @r0
        add r5, r6  /* delay slot */
        /* We should not get here. */
        mov.l L_abort, r0
        jmp @r0
        nop
_start_end:     
        .align  2

L_main:
        .long   __uClibc_start_main /* in libuClibc.*.so */

        .weak   _init
        .type   _init,@function
_init:
        rts
        nop

        .size   _init,.-_init
        .weak   _fini
        .set    _fini,_init

L_init:
      .long   _init
L_fini:
      .long   _fini

#endif

L_abort: 
      .long   abort   

#if defined L_gcrt1 && defined __UCLIBC_PROFILING__
# include "./gmon-start.S"
#endif

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