diff options
Diffstat (limited to 'libquadmath/math/clog10q.c')
| -rw-r--r-- | libquadmath/math/clog10q.c | 57 |
1 files changed, 29 insertions, 28 deletions
diff --git a/libquadmath/math/clog10q.c b/libquadmath/math/clog10q.c index c379bec72b6..a6b46805f00 100644 --- a/libquadmath/math/clog10q.c +++ b/libquadmath/math/clog10q.c @@ -1,5 +1,5 @@ -/* Compute complex base 10 logarithm for complex __float128. - Copyright (C) 1997-2012 Free Software Foundation, Inc. +/* Compute complex base 10 logarithm. + Copyright (C) 1997-2018 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. @@ -19,10 +19,11 @@ #include "quadmath-imp.h" - /* log_10 (2). */ -#define M_LOG10_2q 0.3010299956639811952137388947244930267682Q +#define LOG10_2 0.3010299956639811952137388947244930267682Q +/* pi * log10 (e). */ +#define PI_LOG10E 1.364376353841841347485783625431355770210Q __complex128 clog10q (__complex128 x) @@ -31,15 +32,15 @@ clog10q (__complex128 x) int rcls = fpclassifyq (__real__ x); int icls = fpclassifyq (__imag__ x); - if (__builtin_expect (rcls == QUADFP_ZERO && icls == QUADFP_ZERO, 0)) + if (__glibc_unlikely (rcls == QUADFP_ZERO && icls == QUADFP_ZERO)) { /* Real and imaginary part are 0.0. */ - __imag__ result = signbitq (__real__ x) ? M_PIq : 0.0Q; + __imag__ result = signbitq (__real__ x) ? PI_LOG10E : 0; __imag__ result = copysignq (__imag__ result, __imag__ x); /* Yes, the following line raises an exception. */ - __real__ result = -1.0Q / fabsq (__real__ x); + __real__ result = -1 / fabsq (__real__ x); } - else if (__builtin_expect (rcls != QUADFP_NAN && icls != QUADFP_NAN, 1)) + else if (__glibc_likely (rcls != QUADFP_NAN && icls != QUADFP_NAN)) { /* Neither real nor imaginary part is NaN. */ __float128 absx = fabsq (__real__ x), absy = fabsq (__imag__ x); @@ -52,11 +53,11 @@ clog10q (__complex128 x) absy = t; } - if (absx > FLT128_MAX / 2.0Q) + if (absx > FLT128_MAX / 2) { scale = -1; absx = scalbnq (absx, scale); - absy = (absy >= FLT128_MIN * 2.0Q ? scalbnq (absy, scale) : 0.0Q); + absy = (absy >= FLT128_MIN * 2 ? scalbnq (absy, scale) : 0); } else if (absx < FLT128_MIN && absy < FLT128_MIN) { @@ -65,39 +66,39 @@ clog10q (__complex128 x) absy = scalbnq (absy, scale); } - if (absx == 1.0Q && scale == 0) + if (absx == 1 && scale == 0) { - __float128 absy2 = absy * absy; - if (absy2 <= FLT128_MIN * 2.0Q * M_LN10q) - __real__ result - = (absy2 / 2.0Q - absy2 * absy2 / 4.0Q) * M_LOG10Eq; - else - __real__ result = log1pq (absy2) * (M_LOG10Eq / 2.0Q); + __real__ result = (log1pq (absy * absy) + * ((__float128) M_LOG10Eq / 2)); + math_check_force_underflow_nonneg (__real__ result); } - else if (absx > 1.0Q && absx < 2.0Q && absy < 1.0Q && scale == 0) + else if (absx > 1 && absx < 2 && absy < 1 && scale == 0) { - __float128 d2m1 = (absx - 1.0Q) * (absx + 1.0Q); + __float128 d2m1 = (absx - 1) * (absx + 1); if (absy >= FLT128_EPSILON) d2m1 += absy * absy; - __real__ result = log1pq (d2m1) * (M_LOG10Eq / 2.0Q); + __real__ result = log1pq (d2m1) * ((__float128) M_LOG10Eq / 2); } - else if (absx < 1.0Q - && absx >= 0.75Q - && absy < FLT128_EPSILON / 2.0Q + else if (absx < 1 + && absx >= 0.5Q + && absy < FLT128_EPSILON / 2 && scale == 0) { - __float128 d2m1 = (absx - 1.0Q) * (absx + 1.0Q); - __real__ result = log1pq (d2m1) * (M_LOG10Eq / 2.0Q); + __float128 d2m1 = (absx - 1) * (absx + 1); + __real__ result = log1pq (d2m1) * ((__float128) M_LOG10Eq / 2); } - else if (absx < 1.0Q && (absx >= 0.75Q || absy >= 0.5Q) && scale == 0) + else if (absx < 1 + && absx >= 0.5Q + && scale == 0 + && absx * absx + absy * absy >= 0.5Q) { __float128 d2m1 = __quadmath_x2y2m1q (absx, absy); - __real__ result = log1pq (d2m1) * (M_LOG10Eq / 2.0Q); + __real__ result = log1pq (d2m1) * ((__float128) M_LOG10Eq / 2); } else { __float128 d = hypotq (absx, absy); - __real__ result = log10q (d) - scale * M_LOG10_2q; + __real__ result = log10q (d) - scale * LOG10_2; } __imag__ result = M_LOG10Eq * atan2q (__imag__ x, __real__ x); |