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Diffstat (limited to 'sysdeps/ieee754/ldbl-128/s_scalbnl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128/s_scalbnl.c70
1 files changed, 70 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128/s_scalbnl.c b/sysdeps/ieee754/ldbl-128/s_scalbnl.c
new file mode 100644
index 0000000000..c54f064c0c
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128/s_scalbnl.c
@@ -0,0 +1,70 @@
+/* s_scalbnl.c -- long double version of s_scalbn.c.
+ * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz.
+ */
+   
+/* @(#)s_scalbn.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: $";
+#endif
+
+/*
+ * scalbnl (long double x, int n)
+ * scalbnl(x,n) returns x* 2**n  computed by  exponent
+ * manipulation rather than by actually performing an
+ * exponentiation or a multiplication.
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const long double
+#else
+static long double
+#endif
+two114 = 2.0769187434139310514121985316880384E+34L, /* 0x4071000000000000, 0 */
+twom114 = 4.8148248609680896326399448564623183E-35L, /* 0x3F8D000000000000, 0 */
+huge   = 1.0E+4900L,
+tiny   = 1.0E-4900L;
+
+#ifdef __STDC__
+	long double __scalbnl (long double x, int n)
+#else
+	long double __scalbnl (x,n)
+	long double x; int n;
+#endif
+{
+	int64_t k,hx,lx;
+	GET_LDOUBLE_WORDS64(hx,lx,x);
+        k = (hx>>48)&0x7fff;		/* extract exponent */
+        if (k==0) {				/* 0 or subnormal x */
+            if ((lx|(hx&0x7fffffffffffffffULL))==0) return x; /* +-0 */
+	    x *= two114;
+	    GET_LDOUBLE_MSW64(hx,x);
+	    k = ((hx>>48)&0x7fff) - 114;
+	}
+        if (k==0x7fff) return x+x;		/* NaN or Inf */
+        k = k+n;
+        if (n> 50000 || k > 0x7ffe)
+	  return huge*__copysignl(huge,x); /* overflow  */
+	if (n< -50000) return tiny*__copysignl(tiny,x); /*underflow*/
+        if (k > 0) 				/* normal result */
+	    {SET_LDOUBLE_MSW64(x,(hx&0x8000ffffffffffffULL)|(k<<48)); return x;}
+        if (k <= -114)
+	  return tiny*__copysignl(tiny,x); 	/*underflow*/
+        k += 114;				/* subnormal result */
+	SET_LDOUBLE_MSW64(x,(hx&0x8000ffffffffffffULL)|(k<<48));
+        return x*twom114;
+}
+weak_alias (__scalbnl, scalbnl)