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authorStefan Radomski <github@mintwerk.de>2017-06-27 11:11:13 (GMT)
committerGitHub <noreply@github.com>2017-06-27 11:11:13 (GMT)
commite24393f41834f116038faf6c6d5012575a67136a (patch)
treea1e83679e55781bc92849a07c5acda7b5c09908c /contrib/src/boost/integer/integer_log2.hpp
parentb3a2d91805feb81f79ee52c30a077521912b0bf9 (diff)
parent3a5692f40663282640775f8ff497c4860d265a2a (diff)
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Merge pull request #149 from tklab-tud/sradomski
remerge
Diffstat (limited to 'contrib/src/boost/integer/integer_log2.hpp')
-rw-r--r--contrib/src/boost/integer/integer_log2.hpp224
1 files changed, 112 insertions, 112 deletions
diff --git a/contrib/src/boost/integer/integer_log2.hpp b/contrib/src/boost/integer/integer_log2.hpp
index 411d85e..8b34ce7 100644
--- a/contrib/src/boost/integer/integer_log2.hpp
+++ b/contrib/src/boost/integer/integer_log2.hpp
@@ -1,112 +1,112 @@
-// -----------------------------------------------------------
-// integer_log2.hpp
-//
-// Gives the integer part of the logarithm, in base 2, of a
-// given number. Behavior is undefined if the argument is <= 0.
-//
-// Copyright (c) 2003-2004, 2008 Gennaro Prota
-//
-// 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)
-//
-// -----------------------------------------------------------
-
-#ifndef BOOST_INTEGER_INTEGER_LOG2_HPP
-#define BOOST_INTEGER_INTEGER_LOG2_HPP
-
-#include <assert.h>
-#ifdef __BORLANDC__
-#include <climits>
-#endif
-#include <boost/limits.hpp>
-#include <boost/config.hpp>
-
-
-namespace boost {
- namespace detail {
-
- template <typename T>
- int integer_log2_impl(T x, int n) {
-
- int result = 0;
-
- while (x != 1) {
-
- const T t = static_cast<T>(x >> n);
- if (t) {
- result += n;
- x = t;
- }
- n /= 2;
-
- }
-
- return result;
- }
-
-
-
- // helper to find the maximum power of two
- // less than p (more involved than necessary,
- // to avoid PTS)
- //
- template <int p, int n>
- struct max_pow2_less {
-
- enum { c = 2*n < p };
-
- BOOST_STATIC_CONSTANT(int, value =
- c ? (max_pow2_less< c*p, 2*c*n>::value) : n);
-
- };
-
- template <>
- struct max_pow2_less<0, 0> {
-
- BOOST_STATIC_CONSTANT(int, value = 0);
- };
-
- // this template is here just for Borland :(
- // we could simply rely on numeric_limits but sometimes
- // Borland tries to use numeric_limits<const T>, because
- // of its usual const-related problems in argument deduction
- // - gps
- template <typename T>
- struct width {
-
-#ifdef __BORLANDC__
- BOOST_STATIC_CONSTANT(int, value = sizeof(T) * CHAR_BIT);
-#else
- BOOST_STATIC_CONSTANT(int, value = (std::numeric_limits<T>::digits));
-#endif
-
- };
-
- } // detail
-
-
- // ---------
- // integer_log2
- // ---------------
- //
- template <typename T>
- int integer_log2(T x) {
-
- assert(x > 0);
-
- const int n = detail::max_pow2_less<
- detail::width<T> :: value, 4
- > :: value;
-
- return detail::integer_log2_impl(x, n);
-
- }
-
-
-
-}
-
-
-
-#endif // include guard
+// -----------------------------------------------------------
+// integer_log2.hpp
+//
+// Gives the integer part of the logarithm, in base 2, of a
+// given number. Behavior is undefined if the argument is <= 0.
+//
+// Copyright (c) 2003-2004, 2008 Gennaro Prota
+//
+// 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)
+//
+// -----------------------------------------------------------
+
+#ifndef BOOST_INTEGER_INTEGER_LOG2_HPP
+#define BOOST_INTEGER_INTEGER_LOG2_HPP
+
+#include <assert.h>
+#ifdef __BORLANDC__
+#include <climits>
+#endif
+#include <boost/limits.hpp>
+#include <boost/config.hpp>
+
+
+namespace boost {
+ namespace detail {
+
+ template <typename T>
+ int integer_log2_impl(T x, int n) {
+
+ int result = 0;
+
+ while (x != 1) {
+
+ const T t = static_cast<T>(x >> n);
+ if (t) {
+ result += n;
+ x = t;
+ }
+ n /= 2;
+
+ }
+
+ return result;
+ }
+
+
+
+ // helper to find the maximum power of two
+ // less than p (more involved than necessary,
+ // to avoid PTS)
+ //
+ template <int p, int n>
+ struct max_pow2_less {
+
+ enum { c = 2*n < p };
+
+ BOOST_STATIC_CONSTANT(int, value =
+ c ? (max_pow2_less< c*p, 2*c*n>::value) : n);
+
+ };
+
+ template <>
+ struct max_pow2_less<0, 0> {
+
+ BOOST_STATIC_CONSTANT(int, value = 0);
+ };
+
+ // this template is here just for Borland :(
+ // we could simply rely on numeric_limits but sometimes
+ // Borland tries to use numeric_limits<const T>, because
+ // of its usual const-related problems in argument deduction
+ // - gps
+ template <typename T>
+ struct width {
+
+#ifdef __BORLANDC__
+ BOOST_STATIC_CONSTANT(int, value = sizeof(T) * CHAR_BIT);
+#else
+ BOOST_STATIC_CONSTANT(int, value = (std::numeric_limits<T>::digits));
+#endif
+
+ };
+
+ } // detail
+
+
+ // ---------
+ // integer_log2
+ // ---------------
+ //
+ template <typename T>
+ int integer_log2(T x) {
+
+ assert(x > 0);
+
+ const int n = detail::max_pow2_less<
+ detail::width<T> :: value, 4
+ > :: value;
+
+ return detail::integer_log2_impl(x, n);
+
+ }
+
+
+
+}
+
+
+
+#endif // include guard