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+//////////////////////////////////////////////////////////////////////////////
+//
+// (C) Copyright Stephen Cleary 2000.
+// (C) Copyright Ion Gaztanaga 2007-2012.
+//
+// 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/libs/interprocess for documentation.
+//
+// This file is a slightly modified file from Boost.Pool
+//
+//////////////////////////////////////////////////////////////////////////////
+
+#ifndef BOOST_INTERPROCESS_DETAIL_MATH_FUNCTIONS_HPP
+#define BOOST_INTERPROCESS_DETAIL_MATH_FUNCTIONS_HPP
+
+#include <climits>
+#include <boost/static_assert.hpp>
+
+namespace boost {
+namespace interprocess {
+namespace ipcdetail {
+
+// Greatest common divisor and least common multiple
+
+//
+// gcd is an algorithm that calculates the greatest common divisor of two
+// integers, using Euclid's algorithm.
+//
+// Pre: A > 0 && B > 0
+// Recommended: A > B
+template <typename Integer>
+inline Integer gcd(Integer A, Integer B)
+{
+ do
+ {
+ const Integer tmp(B);
+ B = A % B;
+ A = tmp;
+ } while (B != 0);
+
+ return A;
+}
+
+//
+// lcm is an algorithm that calculates the least common multiple of two
+// integers.
+//
+// Pre: A > 0 && B > 0
+// Recommended: A > B
+template <typename Integer>
+inline Integer lcm(const Integer & A, const Integer & B)
+{
+ Integer ret = A;
+ ret /= gcd(A, B);
+ ret *= B;
+ return ret;
+}
+
+template <typename Integer>
+inline Integer log2_ceil(const Integer & A)
+{
+ Integer i = 0;
+ Integer power_of_2 = 1;
+
+ while(power_of_2 < A){
+ power_of_2 <<= 1;
+ ++i;
+ }
+ return i;
+}
+
+template <typename Integer>
+inline Integer upper_power_of_2(const Integer & A)
+{
+ Integer power_of_2 = 1;
+
+ while(power_of_2 < A){
+ power_of_2 <<= 1;
+ }
+ return power_of_2;
+}
+
+//This function uses binary search to discover the
+//highest set bit of the integer
+inline std::size_t floor_log2 (std::size_t x)
+{
+ const std::size_t Bits = sizeof(std::size_t)*CHAR_BIT;
+ const bool Size_t_Bits_Power_2= !(Bits & (Bits-1));
+ BOOST_STATIC_ASSERT(((Size_t_Bits_Power_2)== true));
+
+ std::size_t n = x;
+ std::size_t log2 = 0;
+
+ for(std::size_t shift = Bits >> 1; shift; shift >>= 1){
+ std::size_t tmp = n >> shift;
+ if (tmp)
+ log2 += shift, n = tmp;
+ }
+
+ return log2;
+}
+
+} // namespace ipcdetail
+} // namespace interprocess
+} // namespace boost
+
+#endif