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diff --git a/newlib/libm/mathfp/e_acosh.c b/newlib/libm/mathfp/e_acosh.c
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+
+/* @(#)e_acosh.c 5.1 93/09/24 */
+
+/*
+FUNCTION
+<<acosh>>, <<acoshf>>---inverse hyperbolic cosine
+
+INDEX
+acosh
+INDEX
+acoshf
+
+ANSI_SYNOPSIS
+        #include <math.h>
+        double acosh(double <[x]>);
+        float acoshf(float <[x]>);
+
+TRAD_SYNOPSIS
+        #include <math.h>
+        double acosh(<[x]>)
+        double <[x]>;
+
+        float acoshf(<[x]>)
+        float <[x]>;
+
+DESCRIPTION
+<<acosh>> calculates the inverse hyperbolic cosine of <[x]>.
+<<acosh>> is defined as
+@ifinfo
+. log(<[x]> + sqrt(<[x]>*<[x]>-1))
+@end ifinfo
+@tex
+$$ln\Bigl(x + \sqrt{x^2-1}\Bigr)$$
+@end tex
+
+<[x]> must be a number greater than or equal to 1.
+
+<<acoshf>> is identical, other than taking and returning floats.
+
+RETURNS
+<<acosh>> and <<acoshf>> return the calculated value.  If <[x]>
+less than 1, the return value is NaN and <<errno>> is set to <<EDOM>>.
+
+You can change the error-handling behavior with the non-ANSI
+<<matherr>> function.
+
+PORTABILITY
+Neither <<acosh>> nor <<acoshf>> are ANSI C.  They are not recommended
+for portable programs.
+
+
+QUICKREF ANSI SVID POSIX RENTRANT
+ acos    n,n,n,m
+ acosf   n,n,n,m
+
+MATHREF
+ acosh, NAN,   arg,DOMAIN,EDOM
+ acosh, < 1.0, NAN,DOMAIN,EDOM
+ acosh, >=1.0, acosh(arg),,,
+
+MATHREF
+ acoshf, NAN,   arg,DOMAIN,EDOM
+ acoshf, < 1.0, NAN,DOMAIN,EDOM
+ acoshf, >=1.0, acosh(arg),,,
+
+*/
+
+/*
+ * ====================================================
+ * 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.
+ * ====================================================
+ *
+ */
+
+/* acosh(x)
+ * Method :
+ *	Based on 
+ *		acosh(x) = log [ x + sqrt(x*x-1) ]
+ *	we have
+ *		acosh(x) := log(x)+ln2,	if x is large; else
+ *		acosh(x) := log(2x-1/(sqrt(x*x-1)+x)) if x>2; else
+ *		acosh(x) := log1p(t+sqrt(2.0*t+t*t)); where t=x-1.
+ *
+ * Special cases:
+ *	acosh(x) is NaN with signal if x<1.
+ *	acosh(NaN) is NaN without signal.
+ */
+
+#include "fdlibm.h"
+
+#ifndef _DOUBLE_IS_32BITS
+
+#ifdef __STDC__
+static const double 
+#else
+static double 
+#endif
+one	= 1.0,
+ln2	= 6.93147180559945286227e-01;  /* 0x3FE62E42, 0xFEFA39EF */
+
+#ifdef __STDC__
+	double acosh(double x)
+#else
+	double acosh(x)
+	double x;
+#endif
+{	
+	double t;
+	__int32_t hx;
+	__uint32_t lx;
+	EXTRACT_WORDS(hx,lx,x);
+	if(hx<0x3ff00000) {		/* x < 1 */
+	    return (x-x)/(x-x);
+	} else if(hx >=0x41b00000) {	/* x > 2**28 */
+	    if(hx >=0x7ff00000) {	/* x is inf of NaN */
+	        return x+x;
+	    } else 
+		return log(x)+ln2;	/* acosh(huge)=log(2x) */
+	} else if(((hx-0x3ff00000)|lx)==0) {
+	    return 0.0;			/* acosh(1) = 0 */
+	} else if (hx > 0x40000000) {	/* 2**28 > x > 2 */
+	    t=x*x;
+	    return log(2.0*x-one/(x+sqrt(t-one)));
+	} else {			/* 1<x<2 */
+	    t = x-one;
+	    return log1p(t+sqrt(2.0*t+t*t));
+	}
+}
+
+#endif /* defined(_DOUBLE_IS_32BITS) */