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-rw-r--r--usr/src/lib/libm/common/LD/scalbl.c72
1 files changed, 72 insertions, 0 deletions
diff --git a/usr/src/lib/libm/common/LD/scalbl.c b/usr/src/lib/libm/common/LD/scalbl.c
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+++ b/usr/src/lib/libm/common/LD/scalbl.c
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+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright 2011 Nexenta Systems, Inc. All rights reserved.
+ */
+/*
+ * Copyright 2006 Sun Microsystems, Inc. All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma weak scalbl = __scalbl
+
+/*
+ * scalbl(x,n): return x * 2**n by manipulating exponent.
+ */
+
+#include "libm.h"
+#include "longdouble.h"
+
+#include <sys/isa_defs.h>
+
+long double
+scalbl(long double x, long double fn) {
+ int *py = (int *) &fn, n;
+ long double z;
+
+ if (isnanl(x) || isnanl(fn))
+ return x * fn;
+
+ /* fn is +/-Inf */
+#if defined(_BIG_ENDIAN)
+ if ((py[0] & 0x7fff0000) == 0x7fff0000) {
+ if ((py[0] & 0x80000000) != 0)
+#else
+ if ((py[2] & 0x7fff) == 0x7fff) {
+ if ((py[2] & 0x8000) != 0)
+#endif
+ return x / (-fn);
+ else
+ return x * fn;
+ }
+ if (rintl(fn) != fn)
+ return (fn - fn) / (fn - fn);
+ if (fn > 65000.0L)
+ z = scalbnl(x, 65000);
+ else if (-fn > 65000.0L)
+ z = scalbnl(x, -65000);
+ else {
+ n = (int) fn;
+ z = scalbnl(x, n);
+ }
+ return z;
+}