| Elliott Hughes | a0ee078 | 2013-01-30 19:06:37 -0800 | [diff] [blame^] | 1 | /*- |
| 2 | * Copyright (c) 2005 Bruce D. Evans and Steven G. Kargl |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice unmodified, this list of conditions, and the following |
| 10 | * disclaimer. |
| 11 | * 2. Redistributions in binary form must reproduce the above copyright |
| 12 | * notice, this list of conditions and the following disclaimer in the |
| 13 | * documentation and/or other materials provided with the distribution. |
| 14 | * |
| 15 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 16 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 17 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 18 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 19 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 20 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 21 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 22 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 23 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 24 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 25 | */ |
| 26 | |
| 27 | /* |
| 28 | * Hyperbolic sine of a complex argument z. See s_csinh.c for details. |
| 29 | */ |
| 30 | |
| 31 | #include <sys/cdefs.h> |
| 32 | __FBSDID("$FreeBSD$"); |
| 33 | |
| 34 | #include <complex.h> |
| 35 | #include <math.h> |
| 36 | |
| 37 | #include "math_private.h" |
| 38 | |
| 39 | static const float huge = 0x1p127; |
| 40 | |
| 41 | float complex |
| 42 | csinhf(float complex z) |
| 43 | { |
| 44 | float x, y, h; |
| 45 | int32_t hx, hy, ix, iy; |
| 46 | |
| 47 | x = crealf(z); |
| 48 | y = cimagf(z); |
| 49 | |
| 50 | GET_FLOAT_WORD(hx, x); |
| 51 | GET_FLOAT_WORD(hy, y); |
| 52 | |
| 53 | ix = 0x7fffffff & hx; |
| 54 | iy = 0x7fffffff & hy; |
| 55 | |
| 56 | if (ix < 0x7f800000 && iy < 0x7f800000) { |
| 57 | if (iy == 0) |
| 58 | return (cpackf(sinhf(x), y)); |
| 59 | if (ix < 0x41100000) /* small x: normal case */ |
| 60 | return (cpackf(sinhf(x) * cosf(y), coshf(x) * sinf(y))); |
| 61 | |
| 62 | /* |x| >= 9, so cosh(x) ~= exp(|x|) */ |
| 63 | if (ix < 0x42b17218) { |
| 64 | /* x < 88.7: expf(|x|) won't overflow */ |
| 65 | h = expf(fabsf(x)) * 0.5f; |
| 66 | return (cpackf(copysignf(h, x) * cosf(y), h * sinf(y))); |
| 67 | } else if (ix < 0x4340b1e7) { |
| 68 | /* x < 192.7: scale to avoid overflow */ |
| 69 | z = __ldexp_cexpf(cpackf(fabsf(x), y), -1); |
| 70 | return (cpackf(crealf(z) * copysignf(1, x), cimagf(z))); |
| 71 | } else { |
| 72 | /* x >= 192.7: the result always overflows */ |
| 73 | h = huge * x; |
| 74 | return (cpackf(h * cosf(y), h * h * sinf(y))); |
| 75 | } |
| 76 | } |
| 77 | |
| 78 | if (ix == 0 && iy >= 0x7f800000) |
| 79 | return (cpackf(copysignf(0, x * (y - y)), y - y)); |
| 80 | |
| 81 | if (iy == 0 && ix >= 0x7f800000) { |
| 82 | if ((hx & 0x7fffff) == 0) |
| 83 | return (cpackf(x, y)); |
| 84 | return (cpackf(x, copysignf(0, y))); |
| 85 | } |
| 86 | |
| 87 | if (ix < 0x7f800000 && iy >= 0x7f800000) |
| 88 | return (cpackf(y - y, x * (y - y))); |
| 89 | |
| 90 | if (ix >= 0x7f800000 && (hx & 0x7fffff) == 0) { |
| 91 | if (iy >= 0x7f800000) |
| 92 | return (cpackf(x * x, x * (y - y))); |
| 93 | return (cpackf(x * cosf(y), INFINITY * sinf(y))); |
| 94 | } |
| 95 | |
| 96 | return (cpackf((x * x) * (y - y), (x + x) * (y - y))); |
| 97 | } |
| 98 | |
| 99 | float complex |
| 100 | csinf(float complex z) |
| 101 | { |
| 102 | |
| 103 | z = csinhf(cpackf(-cimagf(z), crealf(z))); |
| 104 | return (cpackf(cimagf(z), -crealf(z))); |
| 105 | } |