diff options
Diffstat (limited to 'usr/src/lib/libm/common/Q/scalbl.c')
-rw-r--r-- | usr/src/lib/libm/common/Q/scalbl.c | 68 |
1 files changed, 68 insertions, 0 deletions
diff --git a/usr/src/lib/libm/common/Q/scalbl.c b/usr/src/lib/libm/common/Q/scalbl.c new file mode 100644 index 0000000000..7346954a95 --- /dev/null +++ b/usr/src/lib/libm/common/Q/scalbl.c @@ -0,0 +1,68 @@ +/* + * 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" + +#define n0 0 + +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 or NaN + */ + if ((py[n0] & 0x7fff0000) == 0x7fff0000) { + if ((py[n0] & 0x80000000) != 0) + 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); +} |