add fdlibm

git-svn-id: http://svn2.nishi.boats/svn/milsko/trunk@557 b9cfdab3-6d41-4d17-bbe4-086880011989

external/fdlibm/e_scalb.c

@@ -0,0 +1,42 @@
+
+/* @(#)e_scalb.c 1.3 95/01/18 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunSoft, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+/*
+ * __fdlibm_scalb(x, fn) is provide for
+ * passing various standard test suite. One
+ * should use scalbn() instead.
+ */
+
+#include "math.h"
+
+#ifdef _SCALB_INT
+double __fdlibm_scalb(double x, int fn)
+#else
+double __fdlibm_scalb(double x, double fn)
+#endif
+{
+#ifdef _SCALB_INT
+	return scalbn(x, fn);
+#else
+	if(isnan(x) || isnan(fn)) return x * fn;
+	if(!finite(fn)) {
+		if(fn > 0.0) return x * fn;
+		else
+			return x / (-fn);
+	}
+	if(rint(fn) != fn) return (fn - fn) / (fn - fn);
+	if(fn > 65000.0) return scalbn(x, 65000);
+	if(-fn > 65000.0) return scalbn(x, -65000);
+	return scalbn(x, (int)fn);
+#endif
+}