xref: /titanic_41/usr/src/lib/libmvec/common/__vsincosbig.c (revision 8d62b2231107e557adb17ea75579d9c49511457b)
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 #include <sys/isa_defs.h>
31 
32 #ifdef _LITTLE_ENDIAN
33 #define HI(x)	*(1+(int*)x)
34 #define LO(x)	*(unsigned*)x
35 #else
36 #define HI(x)	*(int*)x
37 #define LO(x)	*(1+(unsigned*)x)
38 #endif
39 
40 #ifdef __RESTRICT
41 #define restrict _Restrict
42 #else
43 #define restrict
44 #endif
45 
46 extern const double __vlibm_TBL_sincos_hi[], __vlibm_TBL_sincos_lo[];
47 extern int __vlibm_rem_pio2m(double *, double *, int, int, int);
48 
49 static const double
50 	zero	= 0.0,
51 	one		= 1.0,
52 	two24	= 16777216.0,
53 	pp1		= -1.666666666605760465276263943134982554676e-0001,
54 	pp2		=  8.333261209690963126718376566146180944442e-0003,
55 	p1		= -1.666666666666629669805215138920301589656e-0001,
56 	p2		=  8.333333332390951295683993455280336376663e-0003,
57 	p3		= -1.984126237997976692791551778230098403960e-0004,
58 	p4		=  2.753403624854277237649987622848330351110e-0006,
59 	qq1		= -4.999999999977710986407023955908711557870e-0001,
60 	qq2		=  4.166654863857219350645055881018842089580e-0002,
61 	q1		= -4.999999999999931701464060878888294524481e-0001,
62 	q2		=  4.166666666394861917535640593963708222319e-0002,
63 	q3		= -1.388888552656142867832756687736851681462e-0003,
64 	q4		=  2.478519423681460796618128289454530524759e-0005;
65 
66 void
67 __vlibm_vsincos_big(int n, double * restrict x, int stridex,
68 	double * restrict ss, int stridess,
69 	double * restrict cc, int stridecc, int thresh)
70 {
71 	for (; n--; x += stridex, ss += stridess, cc += stridecc)
72 	{
73 		double		ts, tc, tx, tt[3], ty[2], t, w, z, c, s;
74 		unsigned	hx, xsb;
75 		int			e0, nx, j;
76 
77 		hx = HI(x);
78 		xsb = hx & 0x80000000;
79 		hx &= ~0x80000000;
80 		if (hx <= thresh || hx >= 0x7ff00000)
81 			continue;
82 
83 		/*
84 		 * Argument reduction part.
85 		 */
86 		e0 = (hx >> 20) - 1046;
87 		HI(&tx) = 0x41600000 | (hx & 0xfffff);
88 		LO(&tx) = LO(x);
89 		tt[0] = (double)((int) tx);
90 		tx = (tx - tt[0]) * two24;
91 		if (tx != zero)
92 		{
93 			nx = 2;
94 			tt[1] = (double)((int) tx);
95 			tt[2] = (tx - tt[1]) * two24;
96 			if (tt[2] != zero)
97 				nx = 3;
98 		}
99 		else
100 		{
101 			nx = 1;
102 			tt[1] = tt[2] = zero;
103 		}
104 		nx = __vlibm_rem_pio2m(tt, ty, e0, nx, 2);
105 		if (xsb)
106 		{
107 			nx = -nx;
108 			ty[0] = -ty[0];
109 			ty[1] = -ty[1];
110 		}
111 
112 		/* now nx and ty[*] are the quadrant and reduced arg */
113 		hx = HI(&ty[0]);
114 		xsb = 0;
115 		if (hx & 0x80000000)
116 		{
117 			ty[0] = -ty[0];
118 			ty[1] = -ty[1];
119 			hx &= ~0x80000000;
120 			xsb = 1;
121 		}
122 		if (hx < 0x3fc40000)
123 		{
124 			z = ty[0] * ty[0];
125 			t = z * (q1 + z * (q2 + z * (q3 + z * q4)));
126 			c = one + t;
127 			t = z * (p1 + z * (p2 + z * (p3 + z * p4)));
128 			s = ty[0] + (ty[1] + ty[0] * t);
129 		}
130 		else {
131 			j = (hx + 0x4000) & 0x7fff8000;
132 			HI(&t) = j;
133 			LO(&t) = 0;
134 			ty[0] = (ty[0] - t) + ty[1];
135 			z = ty[0] * ty[0];
136 			t = z * (qq1 + z * qq2);
137 			w = ty[0] * (one + z * (pp1 + z * pp2));
138 			j = ((j - 0x3fc40000) >> 13) & ~3;
139 
140 			c = __vlibm_TBL_sincos_hi[j+1];
141 			tc = __vlibm_TBL_sincos_lo[j+1] - (__vlibm_TBL_sincos_hi[j] * w - c * t);
142 			c += tc;
143 
144 			s = __vlibm_TBL_sincos_hi[j];
145 			ts = (__vlibm_TBL_sincos_hi[j+1] * w + s * t) + __vlibm_TBL_sincos_lo[j];
146 			s += ts;
147 		}
148 		if (xsb) {
149 			s = -s;
150 		}
151 
152 		switch (nx & 3) {
153 		case 0:
154 			*ss = s;
155 			*cc = c;
156 			break;
157 
158 		case 1:
159 			*ss = c;
160 			*cc = -s;
161 			break;
162 
163 		case 2:
164 			*ss = -s;
165 			*cc = -c;
166 			break;
167 
168 		case 3:
169 			*ss = -c;
170 			*cc = s;
171 			break;
172 		}
173 	}
174 }
175