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w_pow.c
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00001 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
00002  *
00003  * ***** BEGIN LICENSE BLOCK *****
00004  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
00005  *
00006  * The contents of this file are subject to the Mozilla Public License Version
00007  * 1.1 (the "License"); you may not use this file except in compliance with
00008  * the License. You may obtain a copy of the License at
00009  * http://www.mozilla.org/MPL/
00010  *
00011  * Software distributed under the License is distributed on an "AS IS" basis,
00012  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
00013  * for the specific language governing rights and limitations under the
00014  * License.
00015  *
00016  * The Original Code is Mozilla Communicator client code, released
00017  * March 31, 1998.
00018  *
00019  * The Initial Developer of the Original Code is
00020  * Sun Microsystems, Inc.
00021  * Portions created by the Initial Developer are Copyright (C) 1998
00022  * the Initial Developer. All Rights Reserved.
00023  *
00024  * Contributor(s):
00025  *
00026  * Alternatively, the contents of this file may be used under the terms of
00027  * either of the GNU General Public License Version 2 or later (the "GPL"),
00028  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
00029  * in which case the provisions of the GPL or the LGPL are applicable instead
00030  * of those above. If you wish to allow use of your version of this file only
00031  * under the terms of either the GPL or the LGPL, and not to allow others to
00032  * use your version of this file under the terms of the MPL, indicate your
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00035  * the provisions above, a recipient may use your version of this file under
00036  * the terms of any one of the MPL, the GPL or the LGPL.
00037  *
00038  * ***** END LICENSE BLOCK ***** */
00039 
00040 
00041 /* @(#)w_pow.c 1.3 95/01/18 */
00042 /*
00043  * ====================================================
00044  * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
00045  *
00046  * Developed at SunSoft, a Sun Microsystems, Inc. business.
00047  * Permission to use, copy, modify, and distribute this
00048  * software is freely granted, provided that this notice 
00049  * is preserved.
00050  * ====================================================
00051  */
00052 
00053 /* 
00054  * wrapper pow(x,y) return x**y
00055  */
00056 
00057 #include "fdlibm.h"
00058 
00059 
00060 #ifdef __STDC__
00061        double fd_pow(double x, double y)  /* wrapper pow */
00062 #else
00063        double fd_pow(x,y)                 /* wrapper pow */
00064        double x,y;
00065 #endif
00066 {
00067 #ifdef _IEEE_LIBM
00068        return  __ieee754_pow(x,y);
00069 #else
00070        double z;
00071     int err;
00072        z=__ieee754_pow(x,y);
00073        if(_LIB_VERSION == _IEEE_|| fd_isnan(y)) return z;
00074        if(fd_isnan(x)) {
00075            if(y==0.0) 
00076                return __kernel_standard(x,y,42,&err); /* pow(NaN,0.0) */
00077            else 
00078               return z;
00079        }
00080        if(x==0.0){ 
00081            if(y==0.0)
00082                return __kernel_standard(x,y,20,&err); /* pow(0.0,0.0) */
00083            if(fd_finite(y)&&y<0.0)
00084                return __kernel_standard(x,y,23,&err); /* pow(0.0,negative) */
00085            return z;
00086        }
00087        if(!fd_finite(z)) {
00088            if(fd_finite(x)&&fd_finite(y)) {
00089                if(fd_isnan(z))
00090                    return __kernel_standard(x,y,24,&err); /* pow neg**non-int */
00091                else 
00092                    return __kernel_standard(x,y,21,&err); /* pow overflow */
00093            }
00094        } 
00095        if(z==0.0&&fd_finite(x)&&fd_finite(y))
00096            return __kernel_standard(x,y,22,&err); /* pow underflow */
00097        return z;
00098 #endif
00099 }