Prepare to convert remaining _Complex functions

This patch has no function changes, except to
ensure the git history correctly tracks the
changes to convert the double version of these
functions into a templated version.

1 files changed, 118 insertions, 0 deletions

diff --git a/math/s_clog_template.c b/math/s_clog_template.c
new file mode 100644
index 0000000000..b546030313
--- /dev/null
+++ b/math/s_clog_template.c
@@ -0,0 +1,118 @@
+/* Compute complex natural logarithm.
+   Copyright (C) 1997-2016 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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <complex.h>
+#include <math.h>
+#include <math_private.h>
+#include <float.h>
+
+__complex__ double
+__clog (__complex__ double x)
+{
+  __complex__ double result;
+  int rcls = fpclassify (__real__ x);
+  int icls = fpclassify (__imag__ x);
+
+  if (__glibc_unlikely (rcls == FP_ZERO && icls == FP_ZERO))
+    {
+      /* Real and imaginary part are 0.0.  */
+      __imag__ result = signbit (__real__ x) ? M_PI : 0.0;
+      __imag__ result = __copysign (__imag__ result, __imag__ x);
+      /* Yes, the following line raises an exception.  */
+      __real__ result = -1.0 / fabs (__real__ x);
+    }
+  else if (__glibc_likely (rcls != FP_NAN && icls != FP_NAN))
+    {
+      /* Neither real nor imaginary part is NaN.  */
+      double absx = fabs (__real__ x), absy = fabs (__imag__ x);
+      int scale = 0;
+
+      if (absx < absy)
+	{
+	  double t = absx;
+	  absx = absy;
+	  absy = t;
+	}
+
+      if (absx > DBL_MAX / 2.0)
+	{
+	  scale = -1;
+	  absx = __scalbn (absx, scale);
+	  absy = (absy >= DBL_MIN * 2.0 ? __scalbn (absy, scale) : 0.0);
+	}
+      else if (absx < DBL_MIN && absy < DBL_MIN)
+	{
+	  scale = DBL_MANT_DIG;
+	  absx = __scalbn (absx, scale);
+	  absy = __scalbn (absy, scale);
+	}
+
+      if (absx == 1.0 && scale == 0)
+	{
+	  __real__ result = __log1p (absy * absy) / 2.0;
+	  math_check_force_underflow_nonneg (__real__ result);
+	}
+      else if (absx > 1.0 && absx < 2.0 && absy < 1.0 && scale == 0)
+	{
+	  double d2m1 = (absx - 1.0) * (absx + 1.0);
+	  if (absy >= DBL_EPSILON)
+	    d2m1 += absy * absy;
+	  __real__ result = __log1p (d2m1) / 2.0;
+	}
+      else if (absx < 1.0
+	       && absx >= 0.5
+	       && absy < DBL_EPSILON / 2.0
+	       && scale == 0)
+	{
+	  double d2m1 = (absx - 1.0) * (absx + 1.0);
+	  __real__ result = __log1p (d2m1) / 2.0;
+	}
+      else if (absx < 1.0
+	       && absx >= 0.5
+	       && scale == 0
+	       && absx * absx + absy * absy >= 0.5)
+	{
+	  double d2m1 = __x2y2m1 (absx, absy);
+	  __real__ result = __log1p (d2m1) / 2.0;
+	}
+      else
+	{
+	  double d = __ieee754_hypot (absx, absy);
+	  __real__ result = __ieee754_log (d) - scale * M_LN2;
+	}
+
+      __imag__ result = __ieee754_atan2 (__imag__ x, __real__ x);
+    }
+  else
+    {
+      __imag__ result = __nan ("");
+      if (rcls == FP_INFINITE || icls == FP_INFINITE)
+	/* Real or imaginary part is infinite.  */
+	__real__ result = HUGE_VAL;
+      else
+	__real__ result = __nan ("");
+    }
+
+  return result;
+}
+weak_alias (__clog, clog)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__clog, __clogl)
+weak_alias (__clog, clogl)
+#endif