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 * Copyright 2011 Nexenta Systems, Inc. All rights reserved. 23 */ 24 /* 25 * Copyright 2005 Sun Microsystems, Inc. All rights reserved. 26 * Use is subject to license terms. 27 */ 28 29 #pragma weak __tanf = tanf 30 31 #include "libm.h" 32 33 extern const int _TBL_ipio2_inf[]; 34 extern int __rem_pio2m(double *, double *, int, int, int, const int *); 35 #if defined(__i386) && !defined(__amd64) 36 extern int __swapRP(int); 37 #endif 38 39 static const double C[] = { 40 1.0, 41 4.46066928428959230679140546271810308098793029785e-0003, 42 4.92165316309189027066395283327437937259674072266e+0000, 43 -7.11410648161473480044492134766187518835067749023e-0001, 44 4.08549808374053391446523164631798863410949707031e+0000, 45 2.50411070398050927821032018982805311679840087891e+0000, 46 1.11492064560251158411574579076841473579406738281e+0001, 47 -1.50565540968422650891511693771462887525558471680e+0000, 48 -1.81484378878349295050043110677506774663925170898e+0000, 49 3.333335997532835641297409611782510896641e-0001, 50 2.999997598248363761541668282006867229939e+00, 51 0.636619772367581343075535, /* 2^ -1 * 1.45F306DC9C883 */ 52 0.5, 53 1.570796326734125614166, /* 2^ 0 * 1.921FB54400000 */ 54 6.077100506506192601475e-11, /* 2^-34 * 1.0B4611A626331 */ 55 }; 56 57 #define one C[0] 58 #define P0 C[1] 59 #define P1 C[2] 60 #define P2 C[3] 61 #define P3 C[4] 62 #define P4 C[5] 63 #define P5 C[6] 64 #define P6 C[7] 65 #define P7 C[8] 66 #define T0 C[9] 67 #define T1 C[10] 68 #define invpio2 C[11] 69 #define half C[12] 70 #define pio2_1 C[13] 71 #define pio2_t C[14] 72 73 float 74 tanf(float x) 75 { 76 double y, z, w; 77 float f; 78 int n, ix, hx, hy; 79 volatile int i; 80 81 hx = *((int *)&x); 82 ix = hx & 0x7fffffff; 83 84 y = (double)x; 85 86 if (ix <= 0x4016cbe4) { /* |x| < 3*pi/4 */ 87 if (ix <= 0x3f490fdb) { /* |x| < pi/4 */ 88 if (ix < 0x3c000000) { /* |x| < 2**-7 */ 89 if (ix <= 0x39800000) { /* |x| < 2**-12 */ 90 i = (int)y; 91 #ifdef lint 92 i = i; 93 #endif 94 return (x); 95 } 96 return ((float)((y * T0) * (T1 + y * y))); 97 } 98 z = y * y; 99 return ((float)(((P0 * y) * (P1 + z * (P2 + z)) * 100 (P3 + z * (P4 + z))) * 101 (P5 + z * (P6 + z * (P7 + z))))); 102 } 103 if (hx > 0) 104 y = (y - pio2_1) - pio2_t; 105 else 106 y = (y + pio2_1) + pio2_t; 107 hy = ((int *)&y)[HIWORD] & ~0x80000000; 108 if (hy < 0x3f800000) { /* |y| < 2**-7 */ 109 z = (y * T0) * (T1 + y * y); 110 return ((float)(-one / z)); 111 } 112 z = y * y; 113 w = ((P0 * y) * (P1 + z * (P2 + z)) * (P3 + z * (P4 + z))) * 114 (P5 + z * (P6 + z * (P7 + z))); 115 return ((float)(-one / w)); 116 } 117 118 if (ix <= 0x49c90fdb) { /* |x| < 2^19*pi */ 119 #if defined(__i386) && !defined(__amd64) 120 int rp; 121 122 rp = __swapRP(fp_extended); 123 #endif 124 w = y * invpio2; 125 if (hx < 0) 126 n = (int)(w - half); 127 else 128 n = (int)(w + half); 129 y = (y - n * pio2_1) - n * pio2_t; 130 #if defined(__i386) && !defined(__amd64) 131 if (rp != fp_extended) 132 (void) __swapRP(rp); 133 #endif 134 } else { 135 if (ix >= 0x7f800000) 136 return (x / x); /* sin(Inf or NaN) is NaN */ 137 hy = ((int *)&y)[HIWORD]; 138 n = ((hy >> 20) & 0x7ff) - 1046; 139 ((int *)&w)[HIWORD] = (hy & 0xfffff) | 0x41600000; 140 ((int *)&w)[LOWORD] = ((int *)&y)[LOWORD]; 141 n = __rem_pio2m(&w, &y, n, 1, 0, _TBL_ipio2_inf); 142 if (hy < 0) { 143 y = -y; 144 n = -n; 145 } 146 } 147 148 hy = ((int *)&y)[HIWORD] & ~0x80000000; 149 if (hy < 0x3f800000) { /* |y| < 2**-7 */ 150 z = (y * T0) * (T1 + y * y); 151 f = ((n & 1) == 0)? (float)z : (float)(-one / z); 152 return (f); 153 } 154 z = y * y; 155 w = ((P0 * y) * (P1 + z * (P2 + z)) * (P3 + z * (P4 + z))) * 156 (P5 + z * (P6 + z * (P7 + z))); 157 f = ((n & 1) == 0)? (float)w : (float)(-one / w); 158 return (f); 159 } 160