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-rw-r--r--sysdeps/libm-ieee754/s_lrintl.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_lrintl.c b/sysdeps/libm-ieee754/s_lrintl.c
new file mode 100644
index 0000000000..8607851669
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+++ b/sysdeps/libm-ieee754/s_lrintl.c
@@ -0,0 +1,86 @@
+/* Round argument to nearest integral value according to current rounding
+   direction.
+   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 long double two63[2] =
+{
+  9.223372036854775808000000e+18, /* 0x403E, 0x00000000, 0x00000000 */
+ -9.223372036854775808000000e+18  /* 0xC03E, 0x00000000, 0x00000000 */
+};
+
+
+long int
+__lrintl (long double x)
+{
+  int32_t se,j0;
+  u_int32_t i0,i1,i;
+  long int result;
+  volatile long double w;
+  long double t;
+  int sx;
+
+  GET_LDOUBLE_WORDS (se, i0, i1, x);
+
+  sx = (se >> 15) & 1;
+  j0 = (se & 0x7fff) - 0x3fff;
+
+  if (j0 < 31)
+    {
+      if (j0 < -1)
+	return 0;
+      else
+	{
+	  w = two63[sx] + x;
+	  t = w - two63[sx];
+	  GET_LDOUBLE_WORDS (se, i0, i1, t);
+	  j0 = (se & 0x7fff) - 0x3fff;
+
+	  result = i0 >> (31 - j0);
+	}
+    }
+  else if (j0 < (int32_t) (8 * sizeof (long int)))
+    {
+      if (j0 >= 63)
+	result = ((long int) i0 << (j0 - 31)) | (i1 << (j0 - 63));
+      else
+	{
+	  w = two63[sx] + x;
+	  t = w - two63[sx];
+	  GET_LDOUBLE_WORDS (se, i0, i1, t);
+	  j0 = (se & 0x7fff) - 0x3fff;
+
+	  result = ((long int) i0 << (j0 - 31)) | (j >> (63 - j0));
+	}
+    }
+  else
+    {
+      /* The number is too large.  It is left implementation defined
+	 what happens.  */
+      return (long int) x;
+    }
+
+  return sx ? -result : result;
+}
+
+weak_alias (__lrintl, lrintl)