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authorUlrich Drepper <drepper@redhat.com>1999-07-14 00:54:57 +0000
committerUlrich Drepper <drepper@redhat.com>1999-07-14 00:54:57 +0000
commitabfbdde177c3a7155070dda1b2cdc8292054cc26 (patch)
treee021306b596381fbf8311d2b7eb294e918ff17c8 /sysdeps/ieee754/ldbl-128/s_scalblnl.c
parent86421aa57ecfd70963ae66848bd6a6dd3b8e0fe6 (diff)
downloadglibc-abfbdde177c3a7155070dda1b2cdc8292054cc26.tar.gz
Update.
Diffstat (limited to 'sysdeps/ieee754/ldbl-128/s_scalblnl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128/s_scalblnl.c70
1 files changed, 70 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128/s_scalblnl.c b/sysdeps/ieee754/ldbl-128/s_scalblnl.c
new file mode 100644
index 0000000000..5e8b58b733
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+++ b/sysdeps/ieee754/ldbl-128/s_scalblnl.c
@@ -0,0 +1,70 @@
+/* s_scalblnl.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
+
+/*
+ * scalblnl (long double x, long int n)
+ * scalblnl(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 __scalblnl (long double x, long int n)
+#else
+ long double __scalblnl (x,n)
+ long double x; long 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 (__scalblnl, scalblnl)