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-rw-r--r--Build/source/libs/mpfr/mpfr-3.1.2/src/uceil_exp2.c65
1 files changed, 65 insertions, 0 deletions
diff --git a/Build/source/libs/mpfr/mpfr-3.1.2/src/uceil_exp2.c b/Build/source/libs/mpfr/mpfr-3.1.2/src/uceil_exp2.c
new file mode 100644
index 00000000000..dd571d0ab96
--- /dev/null
+++ b/Build/source/libs/mpfr/mpfr-3.1.2/src/uceil_exp2.c
@@ -0,0 +1,65 @@
+/* __gmpfr_ceil_exp2 - returns y >= 2^d
+
+Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
+Contributed by the AriC and Caramel projects, INRIA.
+
+This file is part of the GNU MPFR Library.
+
+The GNU MPFR 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 3 of the License, or (at your
+option) any later version.
+
+The GNU MPFR 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 MPFR Library; see the file COPYING.LESSER. If not, see
+http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
+51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
+
+#include "mpfr-impl.h"
+
+/* returns y >= 2^d, assuming that d <= 1024
+ for d integer, returns exactly 2^d
+*/
+double
+__gmpfr_ceil_exp2 (double d)
+{
+ long exp;
+#if _GMP_IEEE_FLOATS
+ union ieee_double_extract x;
+#else
+ struct {double d;} x;
+#endif
+
+ MPFR_ASSERTN(d <= 1024.0);
+ exp = (long) d;
+ if (d != (double) exp)
+ exp++;
+ /* now exp = ceil(d) */
+ x.d = 1.0;
+#if _GMP_IEEE_FLOATS
+ x.s.exp = exp <= -1022 ? 1 : 1023 + exp;
+#else
+ if (exp >= 0)
+ {
+ while (exp != 0)
+ {
+ x.d *= 2.0;
+ exp--;
+ }
+ }
+ else
+ {
+ while (exp != 0)
+ {
+ x.d *= (1.0 / 2.0);
+ exp++;
+ }
+ }
+#endif
+ return x.d;
+}