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authorJoseph Myers <joseph@codesourcery.com>2012-05-19 15:35:29 +0000
committerJoseph Myers <joseph@codesourcery.com>2012-05-19 15:35:29 +0000
commite0b16cc25c4bae1ac45ec6ce90341f9a7d1ae6b6 (patch)
tree82c8f2f5c13fba98b2b028475bf84d9cd15bd6b8 /math/s_ccosh.c
parentf66f0ce833523a47e12b4a3eacab6b20866ab033 (diff)
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Fix ccos, csin, ccosh, csinh overflows (bug 14123).
Diffstat (limited to 'math/s_ccosh.c')
-rw-r--r--math/s_ccosh.c43
1 files changed, 36 insertions, 7 deletions
diff --git a/math/s_ccosh.c b/math/s_ccosh.c
index 2c2b71ceab..44c9944466 100644
--- a/math/s_ccosh.c
+++ b/math/s_ccosh.c
@@ -1,5 +1,5 @@
/* Complex cosine hyperbole function for 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 <drepper@cygnus.com>, 1997.
@@ -20,9 +20,8 @@
#include <complex.h>
#include <fenv.h>
#include <math.h>
-
#include <math_private.h>
-
+#include <float.h>
__complex__ double
__ccosh (__complex__ double x)
@@ -37,14 +36,44 @@ __ccosh (__complex__ double x)
if (__builtin_expect (icls >= FP_ZERO, 1))
{
/* Imaginary part is finite. */
- double sinh_val = __ieee754_sinh (__real__ x);
- double cosh_val = __ieee754_cosh (__real__ x);
+ const int t = (int) ((DBL_MAX_EXP - 1) * M_LN2);
double sinix, cosix;
__sincos (__imag__ x, &sinix, &cosix);
- __real__ retval = cosh_val * cosix;
- __imag__ retval = sinh_val * sinix;
+ if (fabs (__real__ x) > t)
+ {
+ double exp_t = __ieee754_exp (t);
+ double rx = fabs (__real__ x);
+ if (signbit (__real__ x))
+ sinix = -sinix;
+ rx -= t;
+ sinix *= exp_t / 2.0;
+ cosix *= exp_t / 2.0;
+ if (rx > t)
+ {
+ rx -= t;
+ sinix *= exp_t;
+ cosix *= exp_t;
+ }
+ if (rx > t)
+ {
+ /* Overflow (original real part of x > 3t). */
+ __real__ retval = DBL_MAX * cosix;
+ __imag__ retval = DBL_MAX * sinix;
+ }
+ else
+ {
+ double exp_val = __ieee754_exp (rx);
+ __real__ retval = exp_val * cosix;
+ __imag__ retval = exp_val * sinix;
+ }
+ }
+ else
+ {
+ __real__ retval = __ieee754_cosh (__real__ x) * cosix;
+ __imag__ retval = __ieee754_sinh (__real__ x) * sinix;
+ }
}
else
{