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Initial revision

/*
 * Copyright (c) 2005, Kohsuke Ohtani
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the author nor the names of any co-contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * crt0.S - C startup routine
 */

/**
 * Stack layout:
 *      argc            argument counter (integer)
 *      argv[0]         program name (pointer)
 *      argv[1...N]     program args (pointers)
 *      argv[argc-1]    end of args (integer)
 *      NULL
 *      env[0...N]      environment variables (pointers)
 *      NULL
 */

/*
 * Entry point called by kernel first
 */
	.text
	.global _start
_start:
	popl	%ecx			/* Get argc */
	movl	%esp, %ebx		/* Get argv */
	movl	%esp, %eax
	movl	%ecx, %edx
	leal	4(%eax,%edx,4), %eax	/* Get envp */

	xorl	%ebp, %ebp		/* NULL */
	pushl	%ebp			/* Set return address */
	pushl	%ebp

	pushl	%eax			/* Set envp */
	pushl	%ebx			/* Set argv */
	pushl	%ecx			/* Set argc */
	call	__prex_main