xref: /titanic_41/usr/src/lib/libm/common/LD/__sincosl.c (revision aa98ce2c4ecbce8afe8b7b253a911ab24fdded32)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
24  */
25 /*
26  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
27  * Use is subject to license terms.
28  */
29 
30 /* INDENT OFF */
31 /*
32  * long double __k_sincos( long double x, long double y, long double *c )
33  * kernel sincosl function on [-pi/4, pi/4], pi/4 ~ 0.785398164
34  * Input x is assumed to be bounded by ~pi/4 in magnitude.
35  * Input y is the tail of x.
36  * return sinl(x) with *c = cosl(x)
37  *
38  * Table look up algorithm
39  *	see __k_sinl() and __k_cosl()
40  */
41 
42 #include "libm.h"
43 
44 #include <sys/isa_defs.h>
45 
46 extern const long double _TBL_sinl_hi[], _TBL_sinl_lo[], _TBL_cosl_hi[],
47 	_TBL_cosl_lo[];
48 static const long double
49 one	= 1.0,
50 /*
51  * |sin(x) - (x+pp1*x^3+...+pp5*x^11)| <= 2^-122.32 for |x|<1/64
52  */
53 pp1	= -1.666666666666666666666666666586782940810e-0001L,
54 pp2	=  8.333333333333333333333003723660929317540e-0003L,
55 pp3	= -1.984126984126984076045903483778337804470e-0004L,
56 pp4	=  2.755731922361906641319723106210900949413e-0006L,
57 pp5	= -2.505198398570947019093998469135012057673e-0008L,
58 /*
59  * |(sin(x) - (x+p1*x^3+...+p8*x^17)|
60  * |------------------------------- | <= 2^-116.17 for |x|<0.1953125
61  * |                 x              |
62  */
63 p1	=  -1.666666666666666666666666666666211262297e-0001L,
64 p2	=   8.333333333333333333333333301497876908541e-0003L,
65 p3	=  -1.984126984126984126984041302881180621922e-0004L,
66 p4	=   2.755731922398589064100587351307269621093e-0006L,
67 p5	=  -2.505210838544163129378906953765595393873e-0008L,
68 p6	=   1.605904383643244375050998243778534074273e-0010L,
69 p7	=  -7.647162722800685516901456114270824622699e-0013L,
70 p8	=   2.810046428661902961725428841068844462603e-0015L,
71 /*
72  *
73  * |cos(x) - (1+qq1*x^2+...+ qq5*x^10)| <= 2^-123.84 for |x|<=1/128
74  */
75 qq1	=  -4.999999999999999999999999999999378373641e-0001L,
76 qq2	=   4.166666666666666666666665478399327703130e-0002L,
77 qq3	=  -1.388888888888888888058211230618051613494e-0003L,
78 qq4	=   2.480158730156105377771585658905303111866e-0005L,
79 qq5	=  -2.755728099762526325736488376695157008736e-0007L,
80 /*
81  *
82  * |cos(x) - (1+q1*x^2+...+ q8*x^16)| <= 2^-117.11 for |x|<= 0.15625
83  */
84 q1	=  -4.999999999999999999999999999999756416975e-0001L,
85 q2	=   4.166666666666666666666666664006066577258e-0002L,
86 q3	=  -1.388888888888888888888877700363937169637e-0003L,
87 q4	=   2.480158730158730158494468463031814083559e-0005L,
88 q5	=  -2.755731922398586276322819250356005542871e-0007L,
89 q6	=   2.087675698767424261441959760729854017855e-0009L,
90 q7	=  -1.147074481239662089072452129010790774761e-0011L,
91 q8	=   4.777761647399651599730663422263531034782e-0014L;
92 /* INDENT ON */
93 long double
94 __k_sincosl(long double x, long double y, long double *c) {
95 	long double a1, a2, t, t1, t2, z, w;
96 	int *pt = (int *) &t, *px = (int *) &x;
97 	int i, j, hx, ix;
98 
99 	t = 1.0;
100 #if defined(__i386) || defined(__amd64)
101 	XTOI(px, hx);
102 #else
103 	hx = px[0];
104 #endif
105 	ix = hx & 0x7fffffff;
106 	if (ix < 0x3ffc4000) {
107 		if (ix < 0x3fc60000)
108 			if (((int) x) == 0) {
109 				*c = one;
110 				return (x);
111 			}	/* generate inexact */
112 		z = x * x;
113 
114 		if (ix < 0x3ff80000) {
115 			*c = one + z * (qq1 + z * (qq2 + z * (qq3 + z * (qq4 +
116 				z * qq5))));
117 			t = z * (p1 + z * (p2 + z * (p3 + z * (p4 + z * (p5 +
118 				z * p6)))));
119 		} else {
120 			*c = one + z * (q1 + z * (q2 + z * (q3 + z * (q4 + z *
121 				(q5 + z * (q6 + z * (q7 + z * q8)))))));
122 			t = z * (p1 + z * (p2 + z * (p3 + z * (p4 + z * (p5 +
123 				z * (p6 + z * (p7 + z * p8)))))));
124 		}
125 
126 		t = y + x * t;
127 		return (x + t);
128 	}
129 	j = (ix + 0x400) & 0x7ffff800;
130 	i = (j - 0x3ffc4000) >> 11;
131 #if defined(__i386) || defined(__amd64)
132 	ITOX(j, pt);
133 #else
134 	pt[0] = j;
135 #endif
136 	if (hx > 0)
137 		x = y - (t - x);
138 	else
139 		x = (-y) - (t + x);
140 	a1 = _TBL_sinl_hi[i];
141 	z = x * x;
142 	t = z * (qq1 + z * (qq2 + z * (qq3 + z * (qq4 + z * qq5))));
143 	w = x * (one + z * (pp1 + z * (pp2 + z * (pp3 + z * (pp4 + z *
144 		pp5)))));
145 	a2 = _TBL_cosl_hi[i];
146 	t2 = _TBL_cosl_lo[i] - (a1 * w - a2 * t);
147 	*c = a2 + t2;
148 	t1 = a2 * w + a1 * t;
149 	t1 += _TBL_sinl_lo[i];
150 	if (hx < 0)
151 		return (-a1 - t1);
152 	else
153 		return (a1 + t1);
154 }
155