From e0b16cc25c4bae1ac45ec6ce90341f9a7d1ae6b6 Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Sat, 19 May 2012 15:35:29 +0000 Subject: Fix ccos, csin, ccosh, csinh overflows (bug 14123). --- math/s_csinl.c | 43 ++++++++++++++++++++++++++++++++++++------- 1 file changed, 36 insertions(+), 7 deletions(-) (limited to 'math/s_csinl.c') diff --git a/math/s_csinl.c b/math/s_csinl.c index df20e8b338..ff43256e54 100644 --- a/math/s_csinl.c +++ b/math/s_csinl.c @@ -1,5 +1,5 @@ /* Complex sine function for long double. - Copyright (C) 1997, 2011 Free Software Foundation, Inc. + Copyright (C) 1997-2012 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper , 1997. @@ -20,9 +20,8 @@ #include #include #include - #include - +#include __complex__ long double __csinl (__complex__ long double x) @@ -40,14 +39,44 @@ __csinl (__complex__ long double x) if (__builtin_expect (rcls >= FP_ZERO, 1)) { /* Real part is finite. */ - long double sinh_val = __ieee754_sinhl (__imag__ x); - long double cosh_val = __ieee754_coshl (__imag__ x); + const int t = (int) ((LDBL_MAX_EXP - 1) * M_LN2l); long double sinix, cosix; __sincosl (__real__ x, &sinix, &cosix); - __real__ retval = cosh_val * sinix; - __imag__ retval = sinh_val * cosix; + if (fabsl (__imag__ x) > t) + { + long double exp_t = __ieee754_expl (t); + long double ix = fabsl (__imag__ x); + if (signbit (__imag__ x)) + cosix = -cosix; + ix -= t; + sinix *= exp_t / 2.0L; + cosix *= exp_t / 2.0L; + if (ix > t) + { + ix -= t; + sinix *= exp_t; + cosix *= exp_t; + } + if (ix > t) + { + /* Overflow (original imaginary part of x > 3t). */ + __real__ retval = LDBL_MAX * sinix; + __imag__ retval = LDBL_MAX * cosix; + } + else + { + long double exp_val = __ieee754_expl (ix); + __real__ retval = exp_val * sinix; + __imag__ retval = exp_val * cosix; + } + } + else + { + __real__ retval = __ieee754_coshl (__imag__ x) * sinix; + __imag__ retval = __ieee754_sinhl (__imag__ x) * cosix; + } if (negate) __real__ retval = -__real__ retval; -- cgit 1.4.1