1 /*-
2 * ====================================================
3 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
4 *
5 * Developed at SunPro, a Sun Microsystems, Inc. business.
6 * Permission to use, copy, modify, and distribute this
7 * software is freely granted, provided that this notice
8 * is preserved.
9 * ====================================================
10 */
11
12 /* s_sincosf.c -- float version of s_sincos.c.
13 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
14 * Optimized by Bruce D. Evans.
15 * Merged s_sinf.c and s_cosf.c by Steven G. Kargl.
16 */
17
18 #include <sys/cdefs.h>
19 #if 0
20 __FBSDID("$FreeBSD: head/lib/msun/src/s_sincosf.c 319047 2017-05-28 06:13:38Z mmel $");
21 #endif
22 #if defined(LIBM_SCCS) && !defined(lint)
23 __RCSID("$NetBSD: s_sincosf.c,v 1.1 2022/08/27 08:31:59 christos Exp $");
24 #endif
25
26 #include "namespace.h"
27 #include <float.h>
28
29 #include "math.h"
30 #define INLINE_REM_PIO2F
31 #include "math_private.h"
32 #include "e_rem_pio2f.h"
33 #include "k_sincosf.h"
34
35 /* Small multiples of pi/2 rounded to double precision. */
36 static const double
37 p1pio2 = 1*M_PI_2, /* 0x3FF921FB, 0x54442D18 */
38 p2pio2 = 2*M_PI_2, /* 0x400921FB, 0x54442D18 */
39 p3pio2 = 3*M_PI_2, /* 0x4012D97C, 0x7F3321D2 */
40 p4pio2 = 4*M_PI_2; /* 0x401921FB, 0x54442D18 */
41
42 #ifdef __weak_alias
__weak_alias(sincosf,_sincosf)43 __weak_alias(sincosf,_sincosf)
44 #endif
45
46 void
47 sincosf(float x, float *sn, float *cs)
48 {
49 float c, s;
50 double y;
51 int32_t n, hx, ix;
52
53 GET_FLOAT_WORD(hx, x);
54 ix = hx & 0x7fffffff;
55
56 if (ix <= 0x3f490fda) { /* |x| ~<= pi/4 */
57 if (ix < 0x39800000) { /* |x| < 2**-12 */
58 if ((int)x == 0) {
59 *sn = x; /* x with inexact if x != 0 */
60 *cs = 1;
61 return;
62 }
63 }
64 __kernel_sincosdf(x, sn, cs);
65 return;
66 }
67
68 if (ix <= 0x407b53d1) { /* |x| ~<= 5*pi/4 */
69 if (ix <= 0x4016cbe3) { /* |x| ~<= 3pi/4 */
70 if (hx > 0) {
71 __kernel_sincosdf(x - p1pio2, cs, sn);
72 *cs = -*cs;
73 } else {
74 __kernel_sincosdf(x + p1pio2, cs, sn);
75 *sn = -*sn;
76 }
77 } else {
78 if (hx > 0)
79 __kernel_sincosdf(x - p2pio2, sn, cs);
80 else
81 __kernel_sincosdf(x + p2pio2, sn, cs);
82 *sn = -*sn;
83 *cs = -*cs;
84 }
85 return;
86 }
87
88 if (ix <= 0x40e231d5) { /* |x| ~<= 9*pi/4 */
89 if (ix <= 0x40afeddf) { /* |x| ~<= 7*pi/4 */
90 if (hx > 0) {
91 __kernel_sincosdf(x - p3pio2, cs, sn);
92 *sn = -*sn;
93 } else {
94 __kernel_sincosdf(x + p3pio2, cs, sn);
95 *cs = -*cs;
96 }
97 } else {
98 if (hx > 0)
99 __kernel_sincosdf(x - p4pio2, sn, cs);
100 else
101 __kernel_sincosdf(x + p4pio2, sn, cs);
102 }
103 return;
104 }
105
106 /* If x = Inf or NaN, then sin(x) = NaN and cos(x) = NaN. */
107 if (ix >= 0x7f800000) {
108 *sn = x - x;
109 *cs = x - x;
110 return;
111 }
112
113 /* Argument reduction. */
114 n = __ieee754_rem_pio2fd(x, &y);
115 __kernel_sincosdf(y, &s, &c);
116
117 switch(n & 3) {
118 case 0:
119 *sn = s;
120 *cs = c;
121 break;
122 case 1:
123 *sn = c;
124 *cs = -s;
125 break;
126 case 2:
127 *sn = -s;
128 *cs = -c;
129 break;
130 default:
131 *sn = -c;
132 *cs = s;
133 }
134 }
135
136
137