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 __ctanhf = ctanhf 31 32 #include "libm.h" /* expf/expm1f/fabsf/sincosf/sinf/tanhf */ 33 #include "complex_wrapper.h" 34 35 /* INDENT OFF */ 36 static const float four = 4.0F, two = 2.0F, one = 1.0F, zero = 0.0F; 37 /* INDENT ON */ 38 39 fcomplex 40 ctanhf(fcomplex z) { 41 float r, u, v, t, x, y, S, C; 42 int hx, ix, hy, iy; 43 fcomplex ans; 44 45 x = F_RE(z); 46 y = F_IM(z); 47 hx = THE_WORD(x); 48 ix = hx & 0x7fffffff; 49 hy = THE_WORD(y); 50 iy = hy & 0x7fffffff; 51 x = fabsf(x); 52 y = fabsf(y); 53 54 if (iy == 0) { /* ctanh(x,0) = (x,0) for x = 0 or NaN */ 55 F_RE(ans) = tanhf(x); 56 F_IM(ans) = zero; 57 } else if (iy >= 0x7f800000) { /* y is inf or NaN */ 58 if (ix < 0x7f800000) /* catanh(finite x,inf/nan) is nan */ 59 F_RE(ans) = F_IM(ans) = y - y; 60 else if (ix == 0x7f800000) { /* x is inf */ 61 F_RE(ans) = one; 62 F_IM(ans) = zero; 63 } else { 64 F_RE(ans) = x + y; 65 F_IM(ans) = y - y; 66 } 67 } else if (ix >= 0x41600000) { 68 /* 69 * |x| > 14 = prec/2 (14,28,34,60) 70 * ctanh z ~ 1 + i (sin2y)/(exp(2x)) 71 */ 72 F_RE(ans) = one; 73 if (iy < 0x7f000000) /* t = sin(2y) */ 74 S = sinf(y + y); 75 else { 76 (void) sincosf(y, &S, &C); 77 S = (S + S) * C; 78 } 79 if (ix >= 0x7f000000) { /* |x| > max/2 */ 80 if (ix >= 0x7f800000) { /* |x| is inf or NaN */ 81 if (ix > 0x7f800000) /* x is NaN */ 82 F_RE(ans) = F_IM(ans) = x + y; 83 else 84 F_IM(ans) = zero * S; /* x is inf */ 85 } else 86 F_IM(ans) = S * expf(-x); /* underflow */ 87 } else 88 F_IM(ans) = (S + S) * expf(-(x + x)); 89 /* 2 sin 2y / exp(2x) */ 90 } else { 91 /* INDENT OFF */ 92 /* 93 * t*t+2t 94 * ctanh z = --------------------------- 95 * t*t+[4(t+1)(cos y)](cos y) 96 * 97 * [4(t+1)(cos y)]*(sin y) 98 * i -------------------------- 99 * t*t+[4(t+1)(cos y)](cos y) 100 */ 101 /* INDENT ON */ 102 (void) sincosf(y, &S, &C); 103 t = expm1f(x + x); 104 r = (four * C) * (t + one); 105 u = t * t; 106 v = one / (u + r * C); 107 F_RE(ans) = (u + two * t) * v; 108 F_IM(ans) = (r * S) * v; 109 } 110 if (hx < 0) 111 F_RE(ans) = -F_RE(ans); 112 if (hy < 0) 113 F_IM(ans) = -F_IM(ans); 114 return (ans); 115 } 116