1 files changed, 74 insertions, 0 deletions
diff --git a/newlib/libm/ld/e_atanhl.c b/newlib/libm/ld/e_atanhl.c
new file mode 100644
index 000000000..a888426d0
--- /dev/null
+++ b/newlib/libm/ld/e_atanhl.c
@@ -0,0 +1,74 @@
+/* from: FreeBSD: head/lib/msun/src/e_atanh.c 176451 2008-02-22 02:30:36Z das */
+
+/* @(#)e_atanh.c 1.3 95/01/18 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunSoft, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ *
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+/*
+ * See e_atanh.c for complete comments.
+ *
+ * Converted to long double by David Schultz <das@FreeBSD.ORG> and
+ * Bruce D. Evans.
+ */
+
+#include <float.h>
+#ifdef __i386__
+#include <ieeefp.h>
+#endif
+
+#include "fpmath.h"
+#include "math.h"
+#include "math_private.h"
+
+/* EXP_TINY is the threshold below which we use atanh(x) ~= x. */
+#if LDBL_MANT_DIG == 64
+#define	EXP_TINY	-34
+#elif LDBL_MANT_DIG == 113
+#define	EXP_TINY	-58
+#else
+#error "Unsupported long double format"
+#endif
+
+#if LDBL_MAX_EXP != 0x4000
+/* We also require the usual expsign encoding. */
+#error "Unsupported long double format"
+#endif
+
+#define	BIAS	(LDBL_MAX_EXP - 1)
+
+static const double one = 1.0, huge = 1e300;
+static const double zero = 0.0;
+
+long double
+atanhl(long double x)
+{
+	long double t;
+	uint16_t hx, ix;
+
+	ENTERI();
+	GET_LDBL_EXPSIGN(hx, x);
+	ix = hx & 0x7fff;
+	if (ix >= 0x3fff)		/* |x| >= 1, or NaN or misnormal */
+	    RETURNI(fabsl(x) == 1 ? x / zero : (x - x) / (x - x));
+	if (ix < BIAS + EXP_TINY && (huge + x) > zero)
+	    RETURNI(x);			/* x is tiny */
+	SET_LDBL_EXPSIGN(x, ix);
+	if (ix < 0x3ffe) {		/* |x| < 0.5, or misnormal */
+	    t = x+x;
+	    t = 0.5*log1pl(t+t*x/(one-x));
+	} else
+	    t = 0.5*log1pl((x+x)/(one-x));
+	RETURNI((hx & 0x8000) == 0 ? t : -t);
+}