initial import

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diff --git a/sysdeps/generic/log__L.c b/sysdeps/generic/log__L.c
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+/*
+ * Copyright (c) 1985, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)log__L.c	8.1 (Berkeley) 6/4/93";
+#endif /* not lint */
+
+/* log__L(Z)
+ *		LOG(1+X) - 2S			       X
+ * RETURN      ---------------  WHERE Z = S*S,  S = ------- , 0 <= Z <= .0294...
+ *		      S				     2 + X
+ *		     
+ * DOUBLE PRECISION (VAX D FORMAT 56 bits or IEEE DOUBLE 53 BITS)
+ * KERNEL FUNCTION FOR LOG; TO BE USED IN LOG1P, LOG, AND POW FUNCTIONS
+ * CODED IN C BY K.C. NG, 1/19/85; 
+ * REVISED BY K.C. Ng, 2/3/85, 4/16/85.
+ *
+ * Method :
+ *	1. Polynomial approximation: let s = x/(2+x). 
+ *	   Based on log(1+x) = log(1+s) - log(1-s)
+ *		 = 2s + 2/3 s**3 + 2/5 s**5 + .....,
+ *
+ *	   (log(1+x) - 2s)/s is computed by
+ *
+ *	       z*(L1 + z*(L2 + z*(... (L7 + z*L8)...)))
+ *
+ *	   where z=s*s. (See the listing below for Lk's values.) The 
+ *	   coefficients are obtained by a special Remez algorithm. 
+ *
+ * Accuracy:
+ *	Assuming no rounding error, the maximum magnitude of the approximation 
+ *	error (absolute) is 2**(-58.49) for IEEE double, and 2**(-63.63)
+ *	for VAX D format.
+ *
+ * Constants:
+ * The hexadecimal values are the intended ones for the following constants.
+ * The decimal values may be used, provided that the compiler will convert
+ * from decimal to binary accurately enough to produce the hexadecimal values
+ * shown.
+ */
+
+#include "mathimpl.h"
+
+vc(L1, 6.6666666666666703212E-1 ,aaaa,402a,aac5,aaaa,  0, .AAAAAAAAAAAAC5)
+vc(L2, 3.9999999999970461961E-1 ,cccc,3fcc,2684,cccc, -1, .CCCCCCCCCC2684)
+vc(L3, 2.8571428579395698188E-1 ,4924,3f92,5782,92f8, -1, .92492492F85782)
+vc(L4, 2.2222221233634724402E-1 ,8e38,3f63,af2c,39b7, -2, .E38E3839B7AF2C)
+vc(L5, 1.8181879517064680057E-1 ,2eb4,3f3a,655e,cc39, -2, .BA2EB4CC39655E)
+vc(L6, 1.5382888777946145467E-1 ,8551,3f1d,781d,e8c5, -2, .9D8551E8C5781D)
+vc(L7, 1.3338356561139403517E-1 ,95b3,3f08,cd92,907f, -2, .8895B3907FCD92)
+vc(L8, 1.2500000000000000000E-1 ,0000,3f00,0000,0000, -2, .80000000000000)
+
+ic(L1, 6.6666666666667340202E-1, -1, 1.5555555555592)
+ic(L2, 3.9999999999416702146E-1, -2, 1.999999997FF24)
+ic(L3, 2.8571428742008753154E-1, -2, 1.24924941E07B4)
+ic(L4, 2.2222198607186277597E-1, -3, 1.C71C52150BEA6)
+ic(L5, 1.8183562745289935658E-1, -3, 1.74663CC94342F)
+ic(L6, 1.5314087275331442206E-1, -3, 1.39A1EC014045B)
+ic(L7, 1.4795612545334174692E-1, -3, 1.2F039F0085122)
+
+#ifdef vccast
+#define	L1	vccast(L1)
+#define	L2	vccast(L2)
+#define	L3	vccast(L3)
+#define	L4	vccast(L4)
+#define	L5	vccast(L5)
+#define	L6	vccast(L6)
+#define	L7	vccast(L7)
+#define	L8	vccast(L8)
+#endif
+
+double __log__L(z)
+double z;
+{
+#if defined(vax)||defined(tahoe)
+    return(z*(L1+z*(L2+z*(L3+z*(L4+z*(L5+z*(L6+z*(L7+z*L8))))))));
+#else	/* defined(vax)||defined(tahoe) */
+    return(z*(L1+z*(L2+z*(L3+z*(L4+z*(L5+z*(L6+z*L7)))))));
+#endif	/* defined(vax)||defined(tahoe) */
+}