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-rw-r--r--sysdeps/ieee754/dbl-64/s_llround.c81
1 files changed, 81 insertions, 0 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_llround.c b/sysdeps/ieee754/dbl-64/s_llround.c
new file mode 100644
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+++ b/sysdeps/ieee754/dbl-64/s_llround.c
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+/* Round double value to long long int.
+   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"
+
+
+long long int
+__llround (double x)
+{
+  int32_t j0;
+  u_int32_t i1, i0;
+  long long int result;
+  int sign;
+
+  EXTRACT_WORDS (i0, i1, x);
+  j0 = ((i0 >> 20) & 0x7ff) - 0x3ff;
+  sign = (i0 & 0x80000000) != 0 ? -1 : 1;
+  i0 &= 0xfffff;
+  i0 |= 0x100000;
+
+  if (j0 < 20)
+    {
+      if (j0 < 0)
+	return j0 < -1 ? 0 : sign;
+      else
+	{
+	  i0 += 0x80000 >> j0;
+
+	  result = i0 >> (20 - j0);
+	}
+    }
+  else if (j0 < (int32_t) (8 * sizeof (long long int)) - 1)
+    {
+      if (j0 >= 52)
+	result = (((long long int) i0 << 32) | i1) << (j0 - 52);
+      else
+	{
+	  u_int32_t j = i1 + (0x80000000 >> (j0 - 20));
+	  if (j < i1)
+	    ++i0;
+
+	  if (j0 == 20)
+	    result = (long long int) i0;
+	  else
+	    result = ((long long int) i0 << (j0 - 20)) | (j >> (52 - j0));
+	}
+    }
+  else
+    {
+      /* The number is too large.  It is left implementation defined
+	 what happens.  */
+      return (long long int) x;
+    }
+
+  return sign * result;
+}
+
+weak_alias (__llround, llround)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__llround, __llroundl)
+weak_alias (__llround, llroundl)
+#endif