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authorUlrich Drepper <drepper@gmail.com>2011-10-12 11:27:51 -0400
committerUlrich Drepper <drepper@gmail.com>2011-10-12 11:27:51 -0400
commit0ac5ae2335292908f39031b1ea9fe8edce433c0f (patch)
treef9d26c8abc0de39d18d4c13e70f6022cdc6b461f /math/w_exp2f.c
parenta843a204a3e8a0dd53584dad3668771abaec84ac (diff)
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Optimize libm
libm is now somewhat integrated with gcc's -ffinite-math-only option and lots of the wrapper functions have been optimized.
Diffstat (limited to 'math/w_exp2f.c')
-rw-r--r--math/w_exp2f.c26
1 files changed, 8 insertions, 18 deletions
diff --git a/math/w_exp2f.c b/math/w_exp2f.c
index 94c82e2..7215fca 100644
--- a/math/w_exp2f.c
+++ b/math/w_exp2f.c
@@ -6,27 +6,17 @@
#include <math.h>
#include <math_private.h>
-static const float o_threshold= (float) FLT_MAX_EXP;
-static const float u_threshold= (float) (FLT_MIN_EXP - FLT_MANT_DIG - 1);
+static const float o_threshold = (float) FLT_MAX_EXP;
+static const float u_threshold = (float) (FLT_MIN_EXP - FLT_MANT_DIG - 1);
float
-__exp2f (float x) /* wrapper exp2f */
+__exp2f (float x)
{
-#ifdef _IEEE_LIBM
+ if (__builtin_expect (x <= u_threshold || x > o_threshold, 0)
+ && _LIB_VERSION != _IEEE_ && __finitef (x))
+ /* exp2 overflow: 144, exp2 underflow: 145 */
+ return __kernel_standard_f (x, x, 144 + (x <= o_threshold));
+
return __ieee754_exp2f (x);
-#else
- float z;
- z = __ieee754_exp2f (x);
- if (_LIB_VERSION != _IEEE_ && __finitef (x))
- {
- if (x > o_threshold)
- /* exp2 overflow */
- return (float) __kernel_standard ((double) x, (double) x, 144);
- else if (x <= u_threshold)
- /* exp2 underflow */
- return (float) __kernel_standard ((double) x, (double) x, 145);
- }
- return z;
-#endif
}
weak_alias (__exp2f, exp2f)