xref: /illumos-gate/usr/src/lib/libmvec/common/__vsinbig.c (revision 25c28e83beb90e7c80452a7c818c5e6f73a07dc8)
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
__vlibm_vsin_big(int n,double * restrict x,int stridex,double * restrict y,int stridey,int thresh)67 __vlibm_vsin_big(int n, double * restrict x, int stridex, double * restrict y,
68 	int stridey, int thresh)
69 {
70 	for (; n--; x += stridex, y += stridey)
71 	{
72 		double		tx, tt[3], ty[2], t, w, z, a;
73 		unsigned	hx, xsb;
74 		int			e0, nx, j;
75 
76 		hx = HI(x);
77 		xsb = hx & 0x80000000;
78 		hx &= ~0x80000000;
79 		if (hx <= thresh || hx >= 0x7ff00000)
80 			continue;
81 		e0 = (hx >> 20) - 1046;
82 		HI(&tx) = 0x41600000 | (hx & 0xfffff);
83 		LO(&tx) = LO(x);
84 		tt[0] = (double)((int) tx);
85 		tx = (tx - tt[0]) * two24;
86 		if (tx != zero)
87 		{
88 			nx = 2;
89 			tt[1] = (double)((int) tx);
90 			tt[2] = (tx - tt[1]) * two24;
91 			if (tt[2] != zero)
92 				nx = 3;
93 		}
94 		else
95 		{
96 			nx = 1;
97 			tt[1] = tt[2] = zero;
98 		}
99 		nx = __vlibm_rem_pio2m(tt, ty, e0, nx, 2);
100 		if (xsb)
101 		{
102 			nx = -nx;
103 			ty[0] = -ty[0];
104 			ty[1] = -ty[1];
105 		}
106 
107 		/* now nx and ty[*] are the quadrant and reduced arg */
108 		xsb = (nx & 2) << 30;
109 		hx = HI(&ty[0]);
110 		if (nx & 1)
111 		{
112 			if (hx & 0x80000000)
113 			{
114 				ty[0] = -ty[0];
115 				ty[1] = -ty[1];
116 				hx &= ~0x80000000;
117 			}
118 			if (hx < 0x3fc40000)
119 			{
120 				z = ty[0] * ty[0];
121 				t = z * (q1 + z * (q2 + z * (q3 + z * q4)));
122 				a = one + t;
123 			}
124 			else
125 			{
126 				j = (hx + 0x4000) & 0x7fff8000;
127 				HI(&t) = j;
128 				LO(&t) = 0;
129 				ty[0] = (ty[0] - t) + ty[1];
130 				z = ty[0] * ty[0];
131 				t = z * (qq1 + z * qq2);
132 				w = ty[0] * (one + z * (pp1 + z * pp2));
133 				j = ((j - 0x3fc40000) >> 13) & ~3;
134 				a = __vlibm_TBL_sincos_hi[j+1];
135 				t = __vlibm_TBL_sincos_lo[j+1] - (__vlibm_TBL_sincos_hi[j] * w - a * t);
136 				a += t;
137 			}
138 		}
139 		else
140 		{
141 			if (hx & 0x80000000)
142 			{
143 				ty[0] = -ty[0];
144 				ty[1] = -ty[1];
145 				hx &= ~0x80000000;
146 				xsb ^= 0x80000000;
147 			}
148 			if (hx < 0x3fc90000)
149 			{
150 				z = ty[0] * ty[0];
151 				t = z * (p1 + z * (p2 + z * (p3 + z * p4)));
152 				a = ty[0] + (ty[1] + ty[0] * t);
153 			}
154 			else
155 			{
156 				j = (hx + 0x4000) & 0x7fff8000;
157 				HI(&t) = j;
158 				LO(&t) = 0;
159 				ty[0] = (ty[0] - t) + ty[1];
160 				z = ty[0] * ty[0];
161 				t = z * (qq1 + z * qq2);
162 				w = ty[0] * (one + z * (pp1 + z * pp2));
163 				j = ((j - 0x3fc40000) >> 13) & ~3;
164 				a = __vlibm_TBL_sincos_hi[j];
165 				t = (__vlibm_TBL_sincos_hi[j+1] * w + a * t) + __vlibm_TBL_sincos_lo[j];
166 				a += t;
167 			}
168 		}
169 		if (xsb) a = -a;
170 		*y = a;
171 	}
172 }
173