ceph/src/boost/libs/safe_numerics/test/test_checked_xor_constexpr.cpp

   1 //  Copyright (c) 2018 Robert Ramey
   2 //
   3 // Distributed under the Boost Software License, Version 1.0. (See
   4 // accompanying file LICENSE_1_0.txt or copy at
   5 // http://www.boost.org/LICENSE_1_0.txt)
   6
   7 #include <iostream>
   8
   9 #include <boost/core/demangle.hpp>
  10 #include <boost/safe_numerics/checked_result_operations.hpp>
  11 #include <boost/safe_numerics/checked_integer.hpp>
  12
  13 // note: T should be of tyme checked_result<R> for some integer type R
  14 template<class T>
  15 constexpr bool test_checked_xor(
  16     const T & v1,
  17     const T & v2,
  18     char expected_result
  19 ){
  20     using namespace boost::safe_numerics;
  21     const T result = v1 ^ v2;
  22
  23     switch(expected_result){
  24     case '.':
  25         if(result.exception()){
  26             return false;
  27         }
  28         return true;
  29     case '-':
  30         if(safe_numerics_error::negative_overflow_error == result.m_e)
  31             return true;
  32     case '+':
  33         if(safe_numerics_error::positive_overflow_error == result.m_e)
  34             return true;
  35     case '!':
  36         if(safe_numerics_error::range_error == result.m_e)
  37             return true;
  38     }
  39     return false;
  40 }
  41
  42 #include "test_checked_xor.hpp"
  43
  44 template<typename T, typename First, typename Second>
  45 struct test_signed_pair {
  46     static const std::size_t i = First();
  47     static const std::size_t j = Second();
  48     static const bool value = test_checked_xor(
  49         signed_values<T>[i],
  50         signed_values<T>[j],
  51         signed_xor_results[i][j]
  52     );
  53 };
  54
  55 template<typename T, typename First, typename Second>
  56 struct test_unsigned_pair {
  57     static const std::size_t i = First();
  58     static const std::size_t j = Second();
  59     // note: is constexpr really required here?  compilers disagree!
  60     constexpr static const bool value = test_checked_xor(
  61         unsigned_values<T>[i],
  62         unsigned_values<T>[j],
  63         unsigned_xor_results[i][j]
  64     );
  65 };
  66
  67 #include "check_symmetry.hpp"
  68 #include <boost/mp11/algorithm.hpp>
  69
  70 int main(){
  71     using namespace boost::mp11;
  72     check_symmetry(signed_xor_results);
  73     check_symmetry(unsigned_xor_results);
  74
  75     static_assert(
  76         mp_all_of<
  77             mp_product<
  78                 test_signed_pair,
  79                 signed_test_types,
  80                 signed_value_indices, signed_value_indices
  81             >,
  82             mp_to_bool
  83         >(),
  84         "all values for all signed types correctly xor'ed"
  85     );
  86
  87     static_assert(
  88         mp_all_of<
  89             mp_product<
  90                 test_unsigned_pair,
  91                 unsigned_test_types,
  92                 unsigned_value_indices, unsigned_value_indices
  93             >,
  94             mp_to_bool
  95         >(),
  96         "all values for all unsigned types correctly xor'ed"
  97     );
  98
  99     return 0;
 100 }