mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-03 04:01:43 +08:00
0ac5ae2335
libm is now somewhat integrated with gcc's -ffinite-math-only option and lots of the wrapper functions have been optimized.
27 lines
620 B
C
27 lines
620 B
C
/*
|
|
* wrapper exp2(x)
|
|
*/
|
|
|
|
#include <float.h>
|
|
#include <math.h>
|
|
#include <math_private.h>
|
|
|
|
static const double o_threshold = (double) DBL_MAX_EXP;
|
|
static const double u_threshold = (double) (DBL_MIN_EXP - DBL_MANT_DIG - 1);
|
|
|
|
double
|
|
__exp2 (double x)
|
|
{
|
|
if (__builtin_expect (x <= u_threshold || x > o_threshold, 0)
|
|
&& _LIB_VERSION != _IEEE_ && __finite (x))
|
|
/* exp2 overflow: 44, exp2 underflow: 45 */
|
|
return __kernel_standard (x, x, 44 + (x <= o_threshold));
|
|
|
|
return __ieee754_exp2 (x);
|
|
}
|
|
weak_alias (__exp2, exp2)
|
|
#ifdef NO_LONG_DOUBLE
|
|
strong_alias (__exp2, __exp2l)
|
|
weak_alias (__exp2, exp2l)
|
|
#endif
|