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Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/s_cprojl.c')
-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);