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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_logbl.c
parent86421aa57ecfd70963ae66848bd6a6dd3b8e0fe6 (diff)
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Update.
Diffstat (limited to 'sysdeps/ieee754/ldbl-128/s_logbl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128/s_logbl.c46
1 files changed, 46 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128/s_logbl.c b/sysdeps/ieee754/ldbl-128/s_logbl.c
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+/* s_logbl.c -- long double version of s_logb.c.
+ * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz.
+ */
+
+/*
+ * ====================================================
+ * 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
+
+/*
+ * long double logbl(x)
+ * IEEE 754 logb. Included to pass IEEE test suite. Not recommend.
+ * Use ilogb instead.
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+	long double __logbl(long double x)
+#else
+	long double __logbl(x)
+	long double x;
+#endif
+{
+	int64_t lx,hx;
+	GET_LDOUBLE_WORDS64(hx,lx,x);
+	hx &= 0x7fffffffffffffffLL;		/* high |x| */
+	if((hx|lx)==0) return -1.0/fabs(x);
+	if(hx>=0x7fff000000000000LL) return x*x;
+	if((hx>>=48)==0) 			/* IEEE 754 logb */
+		return -16382.0;
+	else
+		return (long double) (hx-0x3fff);
+}
+weak_alias (__logbl, logbl)