/*
 * Copyright (c) 1993 Winning Strategies, Inc.
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by Winning Strategies, Inc.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
 */

/*
 * Written by:
 *	J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc.
 */

#include <machine/asm.h>
#include "errno.h"

/* e^x = 2^(x * log2(e)) */
ENTRY(exp)
	fldl	4(%esp)
#ifdef notyet
	fxam
	fstsw	%ax
	testw	$0x0100,%ax		/* Nan */
	jne	Lnan
	testw	$0x0500,%ax		/* Inf */
	jne	Linf
	testw	$0x????,%ax		/* Zero */
	jne	Lzero
#endif
	fldl2e
	fmulp				/* x * log2(e) */
	fstl	%st(1)
	frndint				/* int(x * log2(e)) */
	fstl	%st(2)
	fsubrp				/* fract(x * log2(e)) */
	f2xm1				/* 2^(fract(x * log2(e))) - 1 */ 
	fld1
	faddp				/* 2^(fract(x * log2(e))) */
	fscale				/* e^x */
	ret

#ifdef notyet
Lnan:
	movl	EDOM,_errno
	ret
Linf:
	movl	ERANGE,_errno
	ftst
	fstsw	%ax
	testw	$0x0100,%ax
	jne	Lminf
	ret
Lminf:
	fldz				
	fstpl	st,st(%1)
	ret
Lzero:
	fld1
	fstpl	st,%st(1)
	ret
#endif