1 /* Complex sine function for float types. 2 Copyright (C) 1997-2018 Free Software Foundation, Inc. 3 This file is part of the GNU C Library. 4 Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. 5 6 The GNU C Library is free software; you can redistribute it and/or 7 modify it under the terms of the GNU Lesser General Public 8 License as published by the Free Software Foundation; either 9 version 2.1 of the License, or (at your option) any later version. 10 11 The GNU C Library is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 Lesser General Public License for more details. 15 16 You should have received a copy of the GNU Lesser General Public 17 License along with the GNU C Library; if not, see 18 <http://www.gnu.org/licenses/>. */ 19 20 #include "quadmath-imp.h" 21 22 __complex128 23 csinq (__complex128 x) 24 { 25 __complex128 retval; 26 int negate = signbitq (__real__ x); 27 int rcls = fpclassifyq (__real__ x); 28 int icls = fpclassifyq (__imag__ x); 29 30 __real__ x = fabsq (__real__ x); 31 32 if (__glibc_likely (icls >= QUADFP_ZERO)) 33 { 34 /* Imaginary part is finite. */ 35 if (__glibc_likely (rcls >= QUADFP_ZERO)) 36 { 37 /* Real part is finite. */ 38 const int t = (int) ((FLT128_MAX_EXP - 1) * M_LN2q); 39 __float128 sinix, cosix; 40 41 if (__glibc_likely (__real__ x > FLT128_MIN)) 42 { 43 sincosq (__real__ x, &sinix, &cosix); 44 } 45 else 46 { 47 sinix = __real__ x; 48 cosix = 1; 49 } 50 51 if (negate) 52 sinix = -sinix; 53 54 if (fabsq (__imag__ x) > t) 55 { 56 __float128 exp_t = expq (t); 57 __float128 ix = fabsq (__imag__ x); 58 if (signbitq (__imag__ x)) 59 cosix = -cosix; 60 ix -= t; 61 sinix *= exp_t / 2; 62 cosix *= exp_t / 2; 63 if (ix > t) 64 { 65 ix -= t; 66 sinix *= exp_t; 67 cosix *= exp_t; 68 } 69 if (ix > t) 70 { 71 /* Overflow (original imaginary part of x > 3t). */ 72 __real__ retval = FLT128_MAX * sinix; 73 __imag__ retval = FLT128_MAX * cosix; 74 } 75 else 76 { 77 __float128 exp_val = expq (ix); 78 __real__ retval = exp_val * sinix; 79 __imag__ retval = exp_val * cosix; 80 } 81 } 82 else 83 { 84 __real__ retval = coshq (__imag__ x) * sinix; 85 __imag__ retval = sinhq (__imag__ x) * cosix; 86 } 87 88 math_check_force_underflow_complex (retval); 89 } 90 else 91 { 92 if (icls == QUADFP_ZERO) 93 { 94 /* Imaginary part is 0.0. */ 95 __real__ retval = __real__ x - __real__ x; 96 __imag__ retval = __imag__ x; 97 } 98 else 99 { 100 __real__ retval = nanq (""); 101 __imag__ retval = nanq (""); 102 103 feraiseexcept (FE_INVALID); 104 } 105 } 106 } 107 else if (icls == QUADFP_INFINITE) 108 { 109 /* Imaginary part is infinite. */ 110 if (rcls == QUADFP_ZERO) 111 { 112 /* Real part is 0.0. */ 113 __real__ retval = copysignq (0, negate ? -1 : 1); 114 __imag__ retval = __imag__ x; 115 } 116 else if (rcls > QUADFP_ZERO) 117 { 118 /* Real part is finite. */ 119 __float128 sinix, cosix; 120 121 if (__glibc_likely (__real__ x > FLT128_MIN)) 122 { 123 sincosq (__real__ x, &sinix, &cosix); 124 } 125 else 126 { 127 sinix = __real__ x; 128 cosix = 1; 129 } 130 131 __real__ retval = copysignq (HUGE_VALQ, sinix); 132 __imag__ retval = copysignq (HUGE_VALQ, cosix); 133 134 if (negate) 135 __real__ retval = -__real__ retval; 136 if (signbitq (__imag__ x)) 137 __imag__ retval = -__imag__ retval; 138 } 139 else 140 { 141 __real__ retval = __real__ x - __real__ x; 142 __imag__ retval = HUGE_VALQ; 143 } 144 } 145 else 146 { 147 if (rcls == QUADFP_ZERO) 148 __real__ retval = copysignq (0, negate ? -1 : 1); 149 else 150 __real__ retval = nanq (""); 151 __imag__ retval = nanq (""); 152 } 153 154 return retval; 155 } 156