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-rw-r--r--REORG.TODO/sysdeps/ieee754/dbl-64/s_round.c83
1 files changed, 83 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/ieee754/dbl-64/s_round.c b/REORG.TODO/sysdeps/ieee754/dbl-64/s_round.c
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index 0000000000..390e3f7180
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+++ b/REORG.TODO/sysdeps/ieee754/dbl-64/s_round.c
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+/* Round double to integer away from zero.
+   Copyright (C) 1997-2017 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 <math.h>
+
+#include <math_private.h>
+
+
+double
+__round (double x)
+{
+  int32_t i0, j0;
+  u_int32_t i1;
+
+  EXTRACT_WORDS (i0, i1, x);
+  j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;
+  if (j0 < 20)
+    {
+      if (j0 < 0)
+	{
+	  i0 &= 0x80000000;
+	  if (j0 == -1)
+	    i0 |= 0x3ff00000;
+	  i1 = 0;
+	}
+      else
+	{
+	  u_int32_t i = 0x000fffff >> j0;
+	  if (((i0 & i) | i1) == 0)
+	    /* X is integral.  */
+	    return x;
+
+	  i0 += 0x00080000 >> j0;
+	  i0 &= ~i;
+	  i1 = 0;
+	}
+    }
+  else if (j0 > 51)
+    {
+      if (j0 == 0x400)
+	/* Inf or NaN.  */
+	return x + x;
+      else
+	return x;
+    }
+  else
+    {
+      u_int32_t i = 0xffffffff >> (j0 - 20);
+      if ((i1 & i) == 0)
+	/* X is integral.  */
+	return x;
+
+      u_int32_t j = i1 + (1 << (51 - j0));
+      if (j < i1)
+	i0 += 1;
+      i1 = j;
+      i1 &= ~i;
+    }
+
+  INSERT_WORDS (x, i0, i1);
+  return x;
+}
+weak_alias (__round, round)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__round, __roundl)
+weak_alias (__round, roundl)
+#endif