xref: /freebsd/lib/msun/bsdsrc/mathimpl.h (revision ad30f8e79bd1007cc2476e491bd21b4f5e389e0a)
1 /*
2  * Copyright (c) 1988, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)mathimpl.h	8.1 (Berkeley) 6/4/93
34  * $FreeBSD$
35  */
36 
37 #ifndef _MATHIMPL_H_
38 #define	_MATHIMPL_H_
39 
40 #include <sys/cdefs.h>
41 #include <math.h>
42 
43 #include "../src/math_private.h"
44 
45 /*
46  * TRUNC() is a macro that sets the trailing 27 bits in the mantissa of an
47  * IEEE double variable to zero.  It must be expression-like for syntactic
48  * reasons, and we implement this expression using an inline function
49  * instead of a pure macro to avoid depending on the gcc feature of
50  * statement-expressions.
51  */
52 #define	TRUNC(d)	(_b_trunc(&(d)))
53 
54 static __inline void
55 _b_trunc(volatile double *_dp)
56 {
57 	uint32_t _lw;
58 
59 	GET_LOW_WORD(_lw, *_dp);
60 	SET_LOW_WORD(*_dp, _lw & 0xf8000000);
61 }
62 
63 struct Double {
64 	double	a;
65 	double	b;
66 };
67 
68 /*
69  * Functions internal to the math package, yet not static.
70  */
71 double	__exp__D(double, double);
72 struct Double __log__D(double);
73 
74 #endif /* !_MATHIMPL_H_ */
75