diff options
Diffstat (limited to 'StdLib/LibC/Math/w_log2.c')
-rw-r--r-- | StdLib/LibC/Math/w_log2.c | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/StdLib/LibC/Math/w_log2.c b/StdLib/LibC/Math/w_log2.c new file mode 100644 index 0000000000..35e4d1fccd --- /dev/null +++ b/StdLib/LibC/Math/w_log2.c @@ -0,0 +1,43 @@ +/* @(#)w_log10.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+#include <LibConfig.h>
+#include <sys/EfiCdefs.h>
+#if defined(LIBM_SCCS) && !defined(lint)
+__RCSID("$NetBSD: w_log2.c,v 1.1 2005/07/21 16:58:39 christos Exp $");
+#endif
+
+/*
+ * wrapper log2(X)
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+
+double
+log2(double x) /* wrapper log10 */
+{
+#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
+}
|