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Diffstat (limited to 'sysdeps/ieee754/dbl-64/s_remquo.c')
-rw-r--r--sysdeps/ieee754/dbl-64/s_remquo.c113
1 files changed, 113 insertions, 0 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_remquo.c b/sysdeps/ieee754/dbl-64/s_remquo.c
new file mode 100644
index 0000000000..6e32efbba2
--- /dev/null
+++ b/sysdeps/ieee754/dbl-64/s_remquo.c
@@ -0,0 +1,113 @@
+/* Compute remainder and a congruent to the quotient.
+   Copyright (C) 1997 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 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 double zero = 0.0;
+
+
+double
+__remquo (double x, double y, int *quo)
+{
+  int32_t hx,hy;
+  u_int32_t sx,lx,ly;
+  int cquo, qs;
+
+  EXTRACT_WORDS (hx, lx, x);
+  EXTRACT_WORDS (hy, ly, y);
+  sx = hx & 0x80000000;
+  qs = sx ^ (hy & 0x80000000);
+  hy &= 0x7fffffff;
+  hx &= 0x7fffffff;
+
+  /* Purge off exception values.  */
+  if ((hy | ly) == 0)
+    return (x * y) / (x * y); 			/* y = 0 */
+  if ((hx >= 0x7ff00000)			/* x not finite */
+      || ((hy >= 0x7ff00000)			/* p is NaN */
+	  && (((hy - 0x7ff00000) | ly) != 0)))
+    return (x * y) / (x * y);
+
+  if (hy <= 0x7fbfffff)
+    x = __ieee754_fmod (x, 8 * y);		/* now x < 8y */
+
+  if (((hx - hy) | (lx - ly)) == 0)
+    {
+      *quo = qs ? -1 : 1;
+      return zero * x;
+    }
+
+  x  = fabs (x);
+  y  = fabs (y);
+  cquo = 0;
+
+  if (x >= 4 * y)
+    {
+      x -= 4 * y;
+      cquo += 4;
+    }
+  if (x >= 2 * y)
+    {
+      x -= 2 * y;
+      cquo += 2;
+    }
+
+  if (hy < 0x00200000)
+    {
+      if (x + x > y)
+	{
+	  x -= y;
+	  ++cquo;
+	  if (x + x >= y)
+	    {
+	      x -= y;
+	      ++cquo;
+	    }
+	}
+    }
+  else
+    {
+      double y_half = 0.5 * y;
+      if (x > y_half)
+	{
+	  x -= y;
+	  ++cquo;
+	  if (x >= y_half)
+	    {
+	      x -= y;
+	      ++cquo;
+	    }
+	}
+    }
+
+  *quo = qs ? -cquo : cquo;
+
+  if (sx)
+    x = -x;
+  return x;
+}
+weak_alias (__remquo, remquo)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__remquo, __remquol)
+weak_alias (__remquo, remquol)
+#endif