fp16.h revision 294783 
1/*-
2 * Copyright (c) 2015 Dag-Erling Sm��rgrav
3 * 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 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: stable/10/sys/dev/syscons/plasma/fp16.h 294783 2016-01-26 08:55:31Z des $
27 */
28
29#ifndef FP16_H_INCLUDED
30#define FP16_H_INCLUDED
31
32typedef signed long long fp16_t;
33
34#define ItoFP16(n)	((signed long long)(n) << 16)
35#define FP16toI(n)	((signed long long)(n) >> 16)
36
37#ifndef _KERNEL
38#define FP16toF(n)	((n) / 65536.0)
39#endif
40
41/* add a and b */
42static inline fp16_t
43fp16_add(fp16_t a, fp16_t b)
44{
45
46	return (a + b);
47}
48
49/* subtract b from a */
50static inline fp16_t
51fp16_sub(fp16_t a, fp16_t b)
52{
53
54	return (a - b);
55}
56
57/* multiply a by b */
58static inline fp16_t
59fp16_mul(fp16_t a, fp16_t b)
60{
61
62	return (a * b >> 16);
63}
64
65/* divide a by b */
66static inline fp16_t
67fp16_div(fp16_t a, fp16_t b)
68{
69
70	return ((a << 16) / b);
71}
72
73/* square root */
74fp16_t fp16_sqrt(fp16_t);
75
76#define FP16_2PI	 411774
77#define FP16_PI		 205887
78#define FP16_PI_2	 102943
79#define FP16_PI_4	  51471
80
81/* sine and cosine */
82fp16_t fp16_sin(fp16_t);
83fp16_t fp16_cos(fp16_t);
84
85#endif
86