initial import

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diff --git a/sysdeps/generic/cosh.c b/sysdeps/generic/cosh.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[] = "@(#)cosh.c	8.1 (Berkeley) 6/4/93";
+#endif /* not lint */
+
+/* COSH(X)
+ * RETURN THE HYPERBOLIC COSINE OF X
+ * DOUBLE PRECISION (VAX D format 56 bits, IEEE DOUBLE 53 BITS)
+ * CODED IN C BY K.C. NG, 1/8/85; 
+ * REVISED BY K.C. NG on 2/8/85, 2/23/85, 3/7/85, 3/29/85, 4/16/85.
+ *
+ * Required system supported functions :
+ *	copysign(x,y)
+ *	scalb(x,N)
+ *
+ * Required kernel function:
+ *	exp(x) 
+ *	exp__E(x,c)	...return exp(x+c)-1-x for |x|<0.3465
+ *
+ * Method :
+ *	1. Replace x by |x|. 
+ *	2. 
+ *		                                        [ exp(x) - 1 ]^2 
+ *	    0        <= x <= 0.3465  :  cosh(x) := 1 + -------------------
+ *			       			           2*exp(x)
+ *
+ *		                                   exp(x) +  1/exp(x)
+ *	    0.3465   <= x <= 22      :  cosh(x) := -------------------
+ *			       			           2
+ *	    22       <= x <= lnovfl  :  cosh(x) := exp(x)/2 
+ *	    lnovfl   <= x <= lnovfl+log(2)
+ *				     :  cosh(x) := exp(x)/2 (avoid overflow)
+ *	    log(2)+lnovfl <  x <  INF:  overflow to INF
+ *
+ *	Note: .3465 is a number near one half of ln2.
+ *
+ * Special cases:
+ *	cosh(x) is x if x is +INF, -INF, or NaN.
+ *	only cosh(0)=1 is exact for finite x.
+ *
+ * Accuracy:
+ *	cosh(x) returns the exact hyperbolic cosine of x nearly rounded.
+ *	In a test run with 768,000 random arguments on a VAX, the maximum
+ *	observed error was 1.23 ulps (units in the last place).
+ *
+ * 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(mln2hi, 8.8029691931113054792E1   ,0f33,43b0,2bdb,c7e2,   7, .B00F33C7E22BDB)
+vc(mln2lo,-4.9650192275318476525E-16 ,1b60,a70f,582a,279e, -50,-.8F1B60279E582A)
+vc(lnovfl, 8.8029691931113053016E1   ,0f33,43b0,2bda,c7e2,   7, .B00F33C7E22BDA)
+
+ic(mln2hi, 7.0978271289338397310E2,    10, 1.62E42FEFA39EF)
+ic(mln2lo, 2.3747039373786107478E-14, -45, 1.ABC9E3B39803F)
+ic(lnovfl, 7.0978271289338397310E2,     9, 1.62E42FEFA39EF)
+
+#ifdef vccast
+#define   mln2hi    vccast(mln2hi)
+#define   mln2lo    vccast(mln2lo)
+#define   lnovfl    vccast(lnovfl)
+#endif
+
+#if defined(vax)||defined(tahoe)
+static max = 126                      ;
+#else	/* defined(vax)||defined(tahoe) */
+static max = 1023                     ;
+#endif	/* defined(vax)||defined(tahoe) */
+
+double cosh(x)
+double x;
+{	
+	static const double half=1.0/2.0,
+		one=1.0, small=1.0E-18; /* fl(1+small)==1 */
+	double t;
+
+#if !defined(vax)&&!defined(tahoe)
+	if(x!=x) return(x);	/* x is NaN */
+#endif	/* !defined(vax)&&!defined(tahoe) */
+	if((x=copysign(x,one)) <= 22)
+	    if(x<0.3465) 
+		if(x<small) return(one+x);
+		else {t=x+__exp__E(x,0.0);x=t+t; return(one+t*t/(2.0+x)); }
+
+	    else /* for x lies in [0.3465,22] */
+	        { t=exp(x); return((t+one/t)*half); }
+
+	if( lnovfl <= x && x <= (lnovfl+0.7)) 
+        /* for x lies in [lnovfl, lnovfl+ln2], decrease x by ln(2^(max+1)) 
+         * and return 2^max*exp(x) to avoid unnecessary overflow 
+         */
+	    return(scalb(exp((x-mln2hi)-mln2lo), max)); 
+
+	else 
+	    return(exp(x)*half);	/* for large x,  cosh(x)=exp(x)/2 */
+}