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authorJakub Jelinek <jakub@redhat.com>2007-07-12 18:26:36 +0000
committerJakub Jelinek <jakub@redhat.com>2007-07-12 18:26:36 +0000
commit0ecb606cb6cf65de1d9fc8a919bceb4be476c602 (patch)
tree2ea1f8305970753e4a657acb2ccc15ca3eec8e2c /math/w_log2.c
parent7d58530341304d403a6626d7f7a1913165fe2f32 (diff)
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2.5-18.1
Diffstat (limited to 'math/w_log2.c')
-rw-r--r--math/w_log2.c32
1 files changed, 32 insertions, 0 deletions
diff --git a/math/w_log2.c b/math/w_log2.c
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--- /dev/null
+++ b/math/w_log2.c
@@ -0,0 +1,32 @@
+/*
+ * wrapper log2(X)
+ */
+
+#include <math.h>
+#include "math_private.h"
+
+double
+__log2 (double x) /* wrapper log2 */
+{
+#ifdef _IEEE_LIBM
+ return __ieee754_log2 (x);
+#else
+ double z;
+ z = __ieee754_log2 (x);
+ if (_LIB_VERSION == _IEEE_ || __isnan (x)) return z;
+ if (x <= 0.0)
+ {
+ if (x == 0.0)
+ return __kernel_standard (x, x, 48); /* log2 (0) */
+ else
+ return __kernel_standard (x, x, 49); /* log2 (x < 0) */
+ }
+ else
+ return z;
+#endif
+}
+weak_alias (__log2, log2)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__log2, __log2l)
+weak_alias (__log2, log2l)
+#endif