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-rw-r--r--sysdeps/ieee754/ldbl-128ibm/s_cprojl.c54
1 files changed, 54 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_cprojl.c b/sysdeps/ieee754/ldbl-128ibm/s_cprojl.c
new file mode 100644
index 0000000000..2167db3d91
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm/s_cprojl.c
@@ -0,0 +1,54 @@
+/* Compute projection of complex long double value to Riemann sphere.
+   Copyright (C) 1997,1999,2006 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 <complex.h>
+#include <math.h>
+#include <math_ldbl_opt.h>
+
+__complex__ long double
+__cprojl (__complex__ long double x)
+{
+  __complex__ long double res;
+
+  if (isnan (__real__ x) && isnan (__imag__ x))
+    return x;
+  else if (!isfinite (__real__ x) || !isfinite (__imag__ x))
+    {
+      __real__ res = INFINITY;
+      __imag__ res = __copysignl (0.0, __imag__ x);
+    }
+  else
+    {
+      long double den = (__real__ x * __real__ x + __imag__ x * __imag__ x
+			 + 1.0);
+
+      __real__ res = (2.0 * __real__ x) / den;
+      __imag__ res = (2.0 * __imag__ x) / den;
+      /* __gcc_qmul does not respect -0.0 so we need the following fixup.  */
+       if (__real__ x == 0.0)
+         __real__ res = __real__ x;
+
+       if (__imag__ x == 0.0)
+         __imag__ res = __imag__ x;
+    }
+
+  return res;
+}
+long_double_symbol (libm, __cprojl, cprojl);