[Boost-commit] svn:boost r63781 - sandbox/SOC/2010/bits_and_ints/boost/integer

Subject: [Boost-commit] svn:boost r63781 - sandbox/SOC/2010/bits_and_ints/boost/integer
From: muriloufg_at_[hidden]
Date: 2010-07-09 13:51:16

Author: murilov
Date: 2010-07-09 13:51:15 EDT (Fri, 09 Jul 2010)
New Revision: 63781
URL: http://svn.boost.org/trac/boost/changeset/63781

Log:
Added static_count_trailing_zeros<> and mpl::count_trailing_zeros<> static metafunctions and its test
Added:
   sandbox/SOC/2010/bits_and_ints/boost/integer/static_count_trailing_zeros.hpp   (contents, props changed)
Text files modified: 
   sandbox/SOC/2010/bits_and_ints/boost/integer/count_trailing_zeros.hpp |     2 +-                                      
   1 files changed, 1 insertions(+), 1 deletions(-)

Modified: sandbox/SOC/2010/bits_and_ints/boost/integer/count_trailing_zeros.hpp
==============================================================================
--- sandbox/SOC/2010/bits_and_ints/boost/integer/count_trailing_zeros.hpp	(original)
+++ sandbox/SOC/2010/bits_and_ints/boost/integer/count_trailing_zeros.hpp	2010-07-09 13:51:15 EDT (Fri, 09 Jul 2010)
@@ -31,7 +31,7 @@
 {
         return pop_count(~value & (value - 1));
 } // count_trailing_zeros
-
+	
 } // boost
 
 #endif

Added: sandbox/SOC/2010/bits_and_ints/boost/integer/static_count_trailing_zeros.hpp
==============================================================================
--- (empty file)
+++ sandbox/SOC/2010/bits_and_ints/boost/integer/static_count_trailing_zeros.hpp	2010-07-09 13:51:15 EDT (Fri, 09 Jul 2010)
@@ -0,0 +1,56 @@
+//  Boost integer/static_count_trailing_zeros.hpp header file  ------------------------------//
+
+//  (C) Copyright Murilo Adriano Vasconcelos 2010.
+//  Distributed under the Boost Software License, Version 1.0. (See
+//  accompanying file LICENSE_1_0.txt or copy at
+//  http://www.boost.org/LICENSE_1_0.txt
+
+//  See http://www.boost.org for updates, documentation, and revision history. 
+
+#ifndef BOOST_STATIC_COUNT_TRAILING_ZEROS_INCLUDED
+#define BOOST_STATIC_COUNT_TRAILING_ZEROS_INCLUDED
+
+#include <boost/cstdint.hpp>
+#include <boost/mpl/integral_c.hpp>
+#include <boost/utility/enable_if.hpp>
+#include <boost/integer/static_pop_count.hpp>
+#include <boost/integer/is_integral_constant.hpp>
+
+/*
+ *	static_count_trailing_zeros and mpl::count_trailing_zeros
+ *		counts the number of consecutive 0's 
+ *		from the least significant bit of integral constants.
+ *
+ *	For example:
+ *	
+ *                                         trailing zeros: vvv vvvv
+ *	const unsigned value = 0xF080; // 0000 0000 1111 0000 1000 0000
+ *  int x = static_count_trailing_zeros<value>::value; // x = 7
+ *
+ *	typedef mpl::integral_c<unsigned, 0xF080> value2;
+ *	int y = mpl::count_trailing_zeros<value2>::value;  // y = 7
+ * 
+ */
+
+namespace boost {
+
+namespace mpl {
+	
+/*
+ *	MPL integral_c<> compatible version
+ */
+template <typename IC, 
+	class Enable = typename enable_if< is_integral_constant<IC> >::type>
+struct count_trailing_zeros : pop_count< integral_c<uintmax_t, ~IC::value & (IC::value - 1)> > 
+{};
+
+}
+
+template <uintmax_t Value>
+struct static_count_trailing_zeros : 
+	mpl::count_trailing_zeros< mpl::integral_c<uintmax_t, Value> >
+{};
+	
+} // boost
+
+#endif