Subversion Repositories openrisc_2011-10-31

/*
 * crt0.S -- startup file for D30V systems.
 *
 * Copyright (c) 1997 Cygnus Support
 *
 * The authors hereby grant permission to use, copy, modify, distribute,
 * and license this software and its documentation for any purpose, provided
 * that existing copyright notices are retained in all copies and that this
 * notice is included verbatim in any distributions. No written agreement,
 * license, or royalty fee is required for any of the authorized uses.
 * Modifications to this software may be copyrighted by their authors
 * and need not follow the licensing terms described here, provided that
 * the new terms are clearly indicated on the first page of each file where
 * they apply.
 */

        .file   "crt0.S"
        .text
        .globl  _start
        .extern main
        .extern exit
        .extern __stack
        .extern __sbss_start
        .extern __sbss_end
        .extern __ebss_start
        .extern __ebss_end
        .extern __bss_start
        .extern __bss_end
        .extern memset
        .type   _start,@function

_start: or.l    sp,r0,__stack

        /* Zero the .sbss area */
        or.l    r2,r0,__sbss_start
        or.l    r4,r0,__sbss_end
        sub     r4,r4,r2        || or.s r3,r0,0
        bsrtnz.l r4,(memset)

        /* Zero the .ebss area */
        or.l    r2,r0,__ebss_start
        or.l    r4,r0,__ebss_end
        sub     r4,r4,r2        || or.s r3,r0,0
        bsrtnz.l r4,(memset)

        /* Zero the .bss area */
        or.l    r2,r0,__bss_start
        or.l    r4,r0,__bss_end
        sub     r4,r4,r2        || or.s r3,r0,0
        bsrtnz.l r4,(memset)

        or.s    r2,r0,0         || or.s r3,r0,0
        or      r4,r0,0         || nop
        jsr.l   (main)
        jsr.l   (exit)
        .size   _start,.-_start