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5261 libm should stop using synonyms.h
5298 fabs is 0-sized, confuses dis(1) and others
Reviewed by: Josef 'Jeff' Sipek <jeffpc@josefsipek.net>
Approved by: Gordon Ross <gwr@nexenta.com>


   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  23  */
  24 /*
  25  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  26  * Use is subject to license terms.
  27  */
  28 
  29 #pragma weak log1p = __log1p
  30 
  31 /* INDENT OFF */
  32 /*
  33  * Method :
  34  *   1. Argument Reduction: find k and f such that
  35  *                      1+x = 2^k * (1+f),
  36  *         where  sqrt(2)/2 < 1+f < sqrt(2) .
  37  *
  38  *      Note. If k=0, then f=x is exact. However, if k != 0, then f
  39  *      may not be representable exactly. In that case, a correction
  40  *      term is need. Let u=1+x rounded. Let c = (1+x)-u, then
  41  *      log(1+x) - log(u) ~ c/u. Thus, we proceed to compute log(u),
  42  *      and add back the correction term c/u.
  43  *      (Note: when x > 2**53, one can simply return log(x))
  44  *
  45  *   2. Approximation of log1p(f).
  46  *      Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s)
  47  *               = 2s + 2/3 s**3 + 2/5 s**5 + .....,
  48  *               = 2s + s*R
  49  *      We use a special Reme algorithm on [0,0.1716] to generate




   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
  23  */
  24 /*
  25  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  26  * Use is subject to license terms.
  27  */
  28 
  29 #pragma weak __log1p = log1p
  30 
  31 /* INDENT OFF */
  32 /*
  33  * Method :
  34  *   1. Argument Reduction: find k and f such that
  35  *                      1+x = 2^k * (1+f),
  36  *         where  sqrt(2)/2 < 1+f < sqrt(2) .
  37  *
  38  *      Note. If k=0, then f=x is exact. However, if k != 0, then f
  39  *      may not be representable exactly. In that case, a correction
  40  *      term is need. Let u=1+x rounded. Let c = (1+x)-u, then
  41  *      log(1+x) - log(u) ~ c/u. Thus, we proceed to compute log(u),
  42  *      and add back the correction term c/u.
  43  *      (Note: when x > 2**53, one can simply return log(x))
  44  *
  45  *   2. Approximation of log1p(f).
  46  *      Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s)
  47  *               = 2s + 2/3 s**3 + 2/5 s**5 + .....,
  48  *               = 2s + s*R
  49  *      We use a special Reme algorithm on [0,0.1716] to generate