1 /*-
2 * Copyright (c) 2017,2023 Steven G. Kargl
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 unmodified, this list of conditions, and the following
10 * disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25 */
26
27 #include <sys/cdefs.h>
28
29 /*
30 * See ../src/s_sinpi.c for implementation details.
31 */
32
33 #define INLINE_KERNEL_SINDF
34 #define INLINE_KERNEL_COSDF
35
36 #include "namespace.h"
37 __weak_alias(sinpif, _sinpif)
38
39 #include "math.h"
40 #include "math_private.h"
41 #include "k_cosdf.c"
42 #include "k_sindf.c"
43
44 #define __kernel_cospif(x) (__kernel_cosdf(M_PI * (x)))
45 #define __kernel_sinpif(x) (__kernel_sindf(M_PI * (x)))
46
47 static const float
48 pi_hi = 3.14160156e+00F, /* 0x40491000 */
49 pi_lo = -8.90890988e-06F; /* 0xb715777a */
50
51 static volatile const float vzero = 0;
52
53 float
sinpif(float x)54 sinpif(float x)
55 {
56 float ax, hi, lo, s;
57 uint32_t hx, ix, j0;
58
59 GET_FLOAT_WORD(hx, x);
60 ix = hx & 0x7fffffff;
61 SET_FLOAT_WORD(ax, ix);
62
63 if (ix < 0x3f800000) { /* |x| < 1 */
64 if (ix < 0x3e800000) { /* |x| < 0.25 */
65 if (ix < 0x38800000) { /* |x| < 0x1p-14 */
66 if (x == 0)
67 return (x);
68 SET_FLOAT_WORD(hi, hx & 0xffff0000);
69 hi *= 0x1p23F;
70 lo = x * 0x1p23F - hi;
71 s = (pi_lo + pi_hi) * lo + pi_lo * hi +
72 pi_hi * hi;
73 return (s * 0x1p-23F);
74 }
75
76 s = __kernel_sinpif(ax);
77 return ((hx & 0x80000000) ? -s : s);
78 }
79
80 if (ix < 0x3f000000) /* |x| < 0.5 */
81 s = __kernel_cospif(0.5F - ax);
82 else if (ix < 0x3f400000) /* |x| < 0.75 */
83 s = __kernel_cospif(ax - 0.5F);
84 else
85 s = __kernel_sinpif(1 - ax);
86 return ((hx & 0x80000000) ? -s : s);
87 }
88
89 if (ix < 0x4b000000) { /* 1 <= |x| < 0x1p23 */
90 FFLOORF(x, j0, ix); /* Integer part of ax. */
91 ax -= x;
92 GET_FLOAT_WORD(ix, ax);
93
94 if (ix == 0)
95 s = 0;
96 else {
97 if (ix < 0x3f000000) { /* |x| < 0.5 */
98 if (ix < 0x3e800000) /* |x| < 0.25 */
99 s = __kernel_sinpif(ax);
100 else
101 s = __kernel_cospif(0.5F - ax);
102 } else {
103 if (ix < 0x3f400000) /* |x| < 0.75 */
104 s = __kernel_cospif(ax - 0.5F);
105 else
106 s = __kernel_sinpif(1 - ax);
107 }
108
109 j0 = (uint32_t)x;
110 s = (j0 & 1) ? -s : s;
111 }
112 return ((hx & 0x80000000) ? -s : s);
113 }
114
115 /* x = +-inf or nan. */
116 if (ix >= 0x7f800000)
117 return (vzero / vzero);
118
119 /*
120 * |x| >= 0x1p23 is always an integer, so return +-0.
121 */
122 return (copysignf(0, x));
123 }
124