/* Return value of complex exponential function for float complex value. Copyright (C) 1997-2015 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ #include <complex.h> #include <fenv.h> #include <math.h> #include <math_private.h> #include <float.h> __complex__ float __cexpf (__complex__ float x) { __complex__ float retval; int rcls = fpclassify (__real__ x); int icls = fpclassify (__imag__ x); if (__glibc_likely (rcls >= FP_ZERO)) { /* Real part is finite. */ if (__glibc_likely (icls >= FP_ZERO)) { /* Imaginary part is finite. */ const int t = (int) ((FLT_MAX_EXP - 1) * M_LN2); float sinix, cosix; if (__glibc_likely (fabsf (__imag__ x) > FLT_MIN)) { __sincosf (__imag__ x, &sinix, &cosix); } else { sinix = __imag__ x; cosix = 1.0f; } if (__real__ x > t) { float exp_t = __ieee754_expf (t); __real__ x -= t; sinix *= exp_t; cosix *= exp_t; if (__real__ x > t) { __real__ x -= t; sinix *= exp_t; cosix *= exp_t; } } if (__real__ x > t) { /* Overflow (original real part of x > 3t). */ __real__ retval = FLT_MAX * cosix; __imag__ retval = FLT_MAX * sinix; } else { float exp_val = __ieee754_expf (__real__ x); __real__ retval = exp_val * cosix; __imag__ retval = exp_val * sinix; } if (fabsf (__real__ retval) < FLT_MIN) { volatile float force_underflow = __real__ retval * __real__ retval; (void) force_underflow; } if (fabsf (__imag__ retval) < FLT_MIN) { volatile float force_underflow = __imag__ retval * __imag__ retval; (void) force_underflow; } } else { /* If the imaginary part is +-inf or NaN and the real part is not +-inf the result is NaN + iNaN. */ __real__ retval = __nanf (""); __imag__ retval = __nanf (""); feraiseexcept (FE_INVALID); } } else if (__glibc_likely (rcls == FP_INFINITE)) { /* Real part is infinite. */ if (__glibc_likely (icls >= FP_ZERO)) { /* Imaginary part is finite. */ float value = signbit (__real__ x) ? 0.0 : HUGE_VALF; if (icls == FP_ZERO) { /* Imaginary part is 0.0. */ __real__ retval = value; __imag__ retval = __imag__ x; } else { float sinix, cosix; if (__glibc_likely (fabsf (__imag__ x) > FLT_MIN)) { __sincosf (__imag__ x, &sinix, &cosix); } else { sinix = __imag__ x; cosix = 1.0f; } __real__ retval = __copysignf (value, cosix); __imag__ retval = __copysignf (value, sinix); } } else if (signbit (__real__ x) == 0) { __real__ retval = HUGE_VALF; __imag__ retval = __nanf (""); if (icls == FP_INFINITE) feraiseexcept (FE_INVALID); } else { __real__ retval = 0.0; __imag__ retval = __copysignf (0.0, __imag__ x); } } else { /* If the real part is NaN the result is NaN + iNaN unless the imaginary part is zero. */ __real__ retval = __nanf (""); if (icls == FP_ZERO) __imag__ retval = __imag__ x; else { __imag__ retval = __nanf (""); if (rcls != FP_NAN || icls != FP_NAN) feraiseexcept (FE_INVALID); } } return retval; } #ifndef __cexpf weak_alias (__cexpf, cexpf) #endif