1 files changed, 76 insertions, 0 deletions
diff --git a/libquadmath/math/catanhq.c b/libquadmath/math/catanhq.c
new file mode 100644
index 000000000..6a86e2d02
--- /dev/null
+++ b/libquadmath/math/catanhq.c
@@ -0,0 +1,76 @@
+/* Return arc hyperbole tangent for __float128 value.
+   Copyright (C) 1997, 1998 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include "quadmath-imp.h"
+
+
+__complex128
+catanhq (__complex128 x)
+{
+  __complex128 res;
+  int rcls = fpclassifyq (__real__ x);
+  int icls = fpclassifyq (__imag__ x);
+
+  if (rcls <= QUADFP_INFINITE || icls <= QUADFP_INFINITE)
+    {
+      if (icls == QUADFP_INFINITE)
+	{
+	  __real__ res = copysignq (0.0, __real__ x);
+	  __imag__ res = copysignq (M_PI_2q, __imag__ x);
+	}
+      else if (rcls == QUADFP_INFINITE || rcls == QUADFP_ZERO)
+	{
+	  __real__ res = copysignq (0.0, __real__ x);
+	  if (icls >= QUADFP_ZERO)
+	    __imag__ res = copysignq (M_PI_2q, __imag__ x);
+	  else
+	    __imag__ res = nanq ("");
+	}
+      else
+	{
+	  __real__ res = nanq ("");
+	  __imag__ res = nanq ("");
+	}
+    }
+  else if (rcls == QUADFP_ZERO && icls == QUADFP_ZERO)
+    {
+      res = x;
+    }
+  else
+    {
+      __float128 i2, num, den;
+
+      i2 = __imag__ x * __imag__ x;
+
+      num = 1.0 + __real__ x;
+      num = i2 + num * num;
+
+      den = 1.0 - __real__ x;
+      den = i2 + den * den;
+
+      __real__ res = 0.25 * (logq (num) - logq (den));
+
+      den = 1 - __real__ x * __real__ x - i2;
+
+      __imag__ res = 0.5 * atan2q (2.0 * __imag__ x, den);
+    }
+
+  return res;
+}