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diff --git a/sysdeps/libm-ieee754/e_coshl.c b/sysdeps/libm-ieee754/e_coshl.c
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+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: e_cosh.c,v 1.7 1995/05/10 20:44:58 jtc Exp $";
+#endif
+
+/* __ieee754_coshl(x)
+ * Method :
+ * mathematically coshl(x) if defined to be (exp(x)+exp(-x))/2
+ * 1. Replace x by |x| (coshl(x) = coshl(-x)).
+ * 2.
+ * [ exp(x) - 1 ]^2
+ * 0 <= x <= ln2/2 : coshl(x) := 1 + -------------------
+ * 2*exp(x)
+ *
+ * exp(x) + 1/exp(x)
+ * ln2/2 <= x <= 22 : coshl(x) := -------------------
+ * 2
+ * 22 <= x <= lnovft : coshl(x) := expl(x)/2
+ * lnovft <= x <= ln2ovft: coshl(x) := expl(x/2)/2 * expl(x/2)
+ * ln2ovft < x : coshl(x) := huge*huge (overflow)
+ *
+ * Special cases:
+ * coshl(x) is |x| if x is +INF, -INF, or NaN.
+ * only coshl(0)=1 is exact for finite x.
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const long double one = 1.0, half=0.5, huge = 1.0e4900L;
+#else
+static long double one = 1.0, half=0.5, huge = 1.0e4900L;
+#endif
+
+#ifdef __STDC__
+ long double __ieee754_coshl(long double x)
+#else
+ long double __ieee754_coshl(x)
+ long double x;
+#endif
+{
+ long double t,w;
+ int32_t ex;
+ u_int32_t mx,lx;
+
+ /* High word of |x|. */
+ GET_LDOUBLE_WORDS(ex,mx,lx,x);
+ ex &= 0x7fff;
+
+ /* x is INF or NaN */
+ if(ex==0x7fff) return x*x;
+
+ /* |x| in [0,0.5*ln2], return 1+expm1l(|x|)^2/(2*expl(|x|)) */
+ if(ex < 0x3ffd || (ex == 0x3ffd && mx < 0xb17217f7u)) {
+ t = __expm1l(fabsl(x));
+ w = one+t;
+ if (ex<0x3fbc) return w; /* cosh(tiny) = 1 */
+ return one+(t*t)/(w+w);
+ }
+
+ /* |x| in [0.5*ln2,22], return (exp(|x|)+1/exp(|x|)/2; */
+ if (ex < 0x4003 || (ex == 0x4003 && mx < 0xb0000000u)) {
+ t = __ieee754_expl(fabsl(x));
+ return half*t+half/t;
+ }
+
+ /* |x| in [22, ln(maxdouble)] return half*exp(|x|) */
+ if (ex < 0x400c || (ex == 0x400c && mx < 0xb1700000u))
+ return half*__ieee754_expl(fabsl(x));
+
+ /* |x| in [log(maxdouble), overflowthresold] */
+ if (ex < 0x400d
+ || (ex == 0x400d && (mx < 0xb170b513u
+ || (mx == 0xb170b513u && lx < 0xa1dfd60cu))))
+ {
+ w = __ieee754_expl(half*fabsl(x));
+ t = half*w;
+ return t*w;
+ }
+
+ /* |x| > overflowthresold, cosh(x) overflow */
+ return huge*huge;
+}