1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2005 Bruce D. Evans and Steven G. Kargl 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice unmodified, this list of conditions, and the following 12 * disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 */ 28 29 /* 30 * Float version of ccosh(). See s_ccosh.c for details. 31 */ 32 33 #include <sys/cdefs.h> 34 __FBSDID("$FreeBSD$"); 35 36 #include <complex.h> 37 #include <math.h> 38 39 #include "math_private.h" 40 41 static const float huge = 0x1p127; 42 43 float complex 44 ccoshf(float complex z) 45 { 46 float x, y, h; 47 int32_t hx, hy, ix, iy; 48 49 x = crealf(z); 50 y = cimagf(z); 51 52 GET_FLOAT_WORD(hx, x); 53 GET_FLOAT_WORD(hy, y); 54 55 ix = 0x7fffffff & hx; 56 iy = 0x7fffffff & hy; 57 58 if (ix < 0x7f800000 && iy < 0x7f800000) { 59 if (iy == 0) 60 return (CMPLXF(coshf(x), x * y)); 61 if (ix < 0x41100000) /* |x| < 9: normal case */ 62 return (CMPLXF(coshf(x) * cosf(y), sinhf(x) * sinf(y))); 63 64 /* |x| >= 9, so cosh(x) ~= exp(|x|) */ 65 if (ix < 0x42b17218) { 66 /* x < 88.7: expf(|x|) won't overflow */ 67 h = expf(fabsf(x)) * 0.5F; 68 return (CMPLXF(h * cosf(y), copysignf(h, x) * sinf(y))); 69 } else if (ix < 0x4340b1e7) { 70 /* x < 192.7: scale to avoid overflow */ 71 z = __ldexp_cexpf(CMPLXF(fabsf(x), y), -1); 72 return (CMPLXF(crealf(z), cimagf(z) * copysignf(1, x))); 73 } else { 74 /* x >= 192.7: the result always overflows */ 75 h = huge * x; 76 return (CMPLXF(h * h * cosf(y), h * sinf(y))); 77 } 78 } 79 80 if (ix == 0) /* && iy >= 0x7f800000 */ 81 return (CMPLXF(y - y, x * copysignf(0, y))); 82 83 if (iy == 0) /* && ix >= 0x7f800000 */ 84 return (CMPLXF(x * x, copysignf(0, x) * y)); 85 86 if (ix < 0x7f800000) /* && iy >= 0x7f800000 */ 87 return (CMPLXF(y - y, x * (y - y))); 88 89 if (ix == 0x7f800000) { 90 if (iy >= 0x7f800000) 91 return (CMPLXF(INFINITY, x * (y - y))); 92 return (CMPLXF(INFINITY * cosf(y), x * sinf(y))); 93 } 94 95 return (CMPLXF((x * x) * (y - y), (x + x) * (y - y))); 96 } 97 98 float complex 99 ccosf(float complex z) 100 { 101 102 return (ccoshf(CMPLXF(-cimagf(z), crealf(z)))); 103 } 104