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 #pragma weak __sinhl = sinhl 31 32 #include "libm.h" 33 #include "longdouble.h" 34 35 /* 36 * sinhl(X) 37 * RETURN THE HYPERBOLIC SINE OF X 38 * 39 * Method : 40 * 1. reduce x to non-negative by sinhl(-x) = - sinhl(x). 41 * 2. 42 * 43 * expm1l(x) + expm1l(x)/(expm1l(x)+1) 44 * 0 <= x <= lnovft : sinhl(x) := -------------------------------- 45 * 2 46 * 47 * lnovft <= x < INF : sinhl(x) := expl(x-MEP1*ln2)*2**ME 48 * 49 * here 50 * lnovft: logrithm of the overflow threshold 51 * = MEP1*ln2 chopped to machine precision. 52 * ME maximum exponent 53 * MEP1 maximum exponent plus 1 54 * 55 * Special cases: 56 * sinhl(x) is x if x is +INF, -INF, or NaN. 57 * only sinhl(0)=0 is exact for finite argument. 58 * 59 */ 60 61 #define ME 16383 62 #define MEP1 16384 63 #define LNOVFT 1.135652340629414394949193107797076342845e+4L 64 /* last 32 bits of LN2HI is zero */ 65 #define LN2HI 6.931471805599453094172319547495844850203e-0001L 66 #define LN2LO 1.667085920830552208890449330400379754169e-0025L 67 68 static const long double 69 half = 0.5L, 70 one = 1.0L, 71 ln2hi = LN2HI, 72 ln2lo = LN2LO, 73 lnovftL = LNOVFT; 74 75 long double 76 sinhl(long double x) { 77 long double r, t; 78 79 if (!finitel(x)) 80 return (x + x); /* sinh of NaN or +-INF is itself */ 81 r = fabsl(x); 82 if (r < lnovftL) { 83 t = expm1l(r); 84 r = copysignl((t + t / (one + t)) * half, x); 85 } else { 86 r = copysignl(expl((r - MEP1 * ln2hi) - MEP1 * ln2lo), x); 87 r = scalbnl(r, ME); 88 } 89 return (r); 90 } 91