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Diffstat (limited to 'REORG.TODO/math/s_clog10_template.c')
| -rw-r--r-- | REORG.TODO/math/s_clog10_template.c | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/REORG.TODO/math/s_clog10_template.c b/REORG.TODO/math/s_clog10_template.c new file mode 100644 index 0000000000..30d87b5a8a --- /dev/null +++ b/REORG.TODO/math/s_clog10_template.c @@ -0,0 +1,128 @@ +/* Compute complex base 10 logarithm. + Copyright (C) 1997-2017 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 <math.h> +#include <math_private.h> +#include <float.h> + +/* log_10 (2). */ +#define LOG10_2 M_LIT (0.3010299956639811952137388947244930267682) + +/* pi * log10 (e). */ +#define PI_LOG10E M_LIT (1.364376353841841347485783625431355770210) + +CFLOAT +M_DECL_FUNC (__clog10) (CFLOAT x) +{ + CFLOAT result; + int rcls = fpclassify (__real__ x); + int icls = fpclassify (__imag__ x); + + if (__glibc_unlikely (rcls == FP_ZERO && icls == FP_ZERO)) + { + /* Real and imaginary part are 0.0. */ + __imag__ result = signbit (__real__ x) ? PI_LOG10E : 0; + __imag__ result = M_COPYSIGN (__imag__ result, __imag__ x); + /* Yes, the following line raises an exception. */ + __real__ result = -1 / M_FABS (__real__ x); + } + else if (__glibc_likely (rcls != FP_NAN && icls != FP_NAN)) + { + /* Neither real nor imaginary part is NaN. */ + FLOAT absx = M_FABS (__real__ x), absy = M_FABS (__imag__ x); + int scale = 0; + + if (absx < absy) + { + FLOAT t = absx; + absx = absy; + absy = t; + } + + if (absx > M_MAX / 2) + { + scale = -1; + absx = M_SCALBN (absx, scale); + absy = (absy >= M_MIN * 2 ? M_SCALBN (absy, scale) : 0); + } + else if (absx < M_MIN && absy < M_MIN) + { + scale = M_MANT_DIG; + absx = M_SCALBN (absx, scale); + absy = M_SCALBN (absy, scale); + } + + if (absx == 1 && scale == 0) + { + __real__ result = (M_LOG1P (absy * absy) + * ((FLOAT) M_MLIT (M_LOG10E) / 2)); + math_check_force_underflow_nonneg (__real__ result); + } + else if (absx > 1 && absx < 2 && absy < 1 && scale == 0) + { + FLOAT d2m1 = (absx - 1) * (absx + 1); + if (absy >= M_EPSILON) + d2m1 += absy * absy; + __real__ result = M_LOG1P (d2m1) * ((FLOAT) M_MLIT (M_LOG10E) / 2); + } + else if (absx < 1 + && absx >= M_LIT (0.5) + && absy < M_EPSILON / 2 + && scale == 0) + { + FLOAT d2m1 = (absx - 1) * (absx + 1); + __real__ result = M_LOG1P (d2m1) * ((FLOAT) M_MLIT (M_LOG10E) / 2); + } + else if (absx < 1 + && absx >= M_LIT (0.5) + && scale == 0 + && absx * absx + absy * absy >= M_LIT (0.5)) + { + FLOAT d2m1 = M_SUF (__x2y2m1) (absx, absy); + __real__ result = M_LOG1P (d2m1) * ((FLOAT) M_MLIT (M_LOG10E) / 2); + } + else + { + FLOAT d = M_HYPOT (absx, absy); + __real__ result = M_SUF (__ieee754_log10) (d) - scale * LOG10_2; + } + + __imag__ result = M_MLIT (M_LOG10E) * M_ATAN2 (__imag__ x, __real__ x); + } + else + { + __imag__ result = M_NAN; + if (rcls == FP_INFINITE || icls == FP_INFINITE) + /* Real or imaginary part is infinite. */ + __real__ result = M_HUGE_VAL; + else + __real__ result = M_NAN; + } + + return result; +} + +declare_mgen_alias (__clog10, clog10) + +#if M_LIBM_NEED_COMPAT (clog10) +/* __clog10 is also a public symbol. */ +declare_mgen_libm_compat (__clog10, __clog10) +declare_mgen_libm_compat (clog10, clog10) +#endif |