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diff --git a/sysdeps/ieee754/ldbl-128/e_acoshl.c b/sysdeps/ieee754/ldbl-128/e_acoshl.c
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+/* e_acoshl.c -- long double version of e_acosh.c.
+ * Conversion to long double by Jakub Jelinek, jj@ultra.linux.cz.
+ */
+
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ */
+
+/* __ieee754_acoshl(x)
+ * Method :
+ * Based on
+ * acoshl(x) = logl [ x + sqrtl(x*x-1) ]
+ * we have
+ * acoshl(x) := logl(x)+ln2, if x is large; else
+ * acoshl(x) := logl(2x-1/(sqrtl(x*x-1)+x)) if x>2; else
+ * acoshl(x) := log1pl(t+sqrtl(2.0*t+t*t)); where t=x-1.
+ *
+ * Special cases:
+ * acoshl(x) is NaN with signal if x<1.
+ * acoshl(NaN) is NaN without signal.
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+static const long double
+#else
+static long double
+#endif
+one = 1.0,
+ln2 = 0.6931471805599453094172321214581766L;
+
+#ifdef __STDC__
+ long double __ieee754_acoshl(long double x)
+#else
+ long double __ieee754_acoshl(x)
+ long double x;
+#endif
+{
+ long double t;
+ u_int64_t lx;
+ int64_t hx;
+ GET_LDOUBLE_WORDS64(hx,lx,x);
+ if(hx<0x3fff000000000000LL) { /* x < 1 */
+ return (x-x)/(x-x);
+ } else if(hx >=0x401b000000000000LL) { /* x > 2**28 */
+ if(hx >=0x7fff000000000000LL) { /* x is inf of NaN */
+ return x+x;
+ } else
+ return __ieee754_logl(x)+ln2; /* acoshl(huge)=logl(2x) */
+ } else if(((hx-0x3fff000000000000LL)|lx)==0) {
+ return 0.0L; /* acosh(1) = 0 */
+ } else if (hx > 0x4000000000000000LL) { /* 2**28 > x > 2 */
+ t=x*x;
+ return __ieee754_logl(2.0L*x-one/(x+__ieee754_sqrtl(t-one)));
+ } else { /* 1<x<2 */
+ t = x-one;
+ return __log1pl(t+__sqrtl(2.0L*t+t*t));
+ }
+}