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-rw-r--r--math/e_scalb.c71
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diff --git a/math/e_scalb.c b/math/e_scalb.c
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+/* @(#)e_scalb.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.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: e_scalb.c,v 1.6 1995/05/10 20:46:09 jtc Exp $";
+#endif
+
+/*
+ * __ieee754_scalb(x, fn) is provide for
+ * passing various standard test suite. One
+ * should use scalbn() instead.
+ */
+
+#include <fenv.h>
+#include <math.h>
+#include "math_private.h"
+
+#ifdef _SCALB_INT
+#ifdef __STDC__
+	double __ieee754_scalb(double x, int fn)
+#else
+	double __ieee754_scalb(x,fn)
+	double x; int fn;
+#endif
+#else
+#ifdef __STDC__
+	double __ieee754_scalb(double x, double fn)
+#else
+	double __ieee754_scalb(x,fn)
+	double x, fn;
+#endif
+#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 if (x == 0)
+	      return x;
+	    else if (!__finite (x))
+	      {
+# ifdef FE_INVALID
+		feraiseexcept (FE_INVALID);
+# endif
+		return __nan ("");
+	      }
+	    else       return x/(-fn);
+	}
+	if (__rint(fn)!=fn)
+	  {
+# ifdef FE_INVALID
+	    feraiseexcept (FE_INVALID);
+# endif
+	    return __nan ("");
+	  }
+	if ( fn > 65000.0) return __scalbn(x, 65000);
+	if (-fn > 65000.0) return __scalbn(x,-65000);
+	return __scalbn(x,(int)fn);
+#endif
+}