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-rw-r--r--sysdeps/powerpc/fpu/k_cosf.c65
1 files changed, 65 insertions, 0 deletions
diff --git a/sysdeps/powerpc/fpu/k_cosf.c b/sysdeps/powerpc/fpu/k_cosf.c
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+++ b/sysdeps/powerpc/fpu/k_cosf.c
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+/* k_cosf.c -- float version of k_cos.c
+   Copyright (C) 2011 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Adhemerval Zanella <azanella@br.ibm.com>, 2011
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include "math.h"
+#include "math_private.h"
+
+static const float twom27   = 7.4505806e-09;
+static const float dot3     = 3.0000001e-01;
+static const float dot78125 = 7.8125000e-01;
+
+static const float one =  1.0000000000e+00;
+static const float C1  =  4.1666667908e-02;
+static const float C2  = -1.3888889225e-03;
+static const float C3  =  2.4801587642e-05;
+static const float C4  = -2.7557314297e-07;
+static const float C5  =  2.0875723372e-09;
+static const float C6  = -1.1359647598e-11;
+
+float
+__kernel_cosf (float x, float y)
+{
+  float a, hz, z, r, qx;
+  float ix;
+  ix = __builtin_fabsf (x);
+  if (ix < twom27)
+    {				/* |x| < 2**-27 */
+      if (x == 0.0)
+	return one;
+    }
+  z = x * x;
+  r = z * (C1 + z * (C2 + z * (C3 + z * (C4 + z * (C5 + z * C6)))));
+  if (ix < dot3)		/* if |x| < 0.3 */
+    return one - ((float) 0.5 * z - (z * r - x * y));
+  else
+    {
+      if (ix > dot78125)
+	{			/* x > 0.78125 */
+	  qx = (float) 0.28125;
+	}
+      else
+	{
+	  qx = ix / 4.0;
+	}
+      hz = (float) 0.5 *z - qx;
+      a = one - qx;
+      return a - (hz - (z * r - x * y));
+    }
+}