addition_overflow.cpp raw

   1  // Copyright (c) 2020-present The Bitcoin Core developers
   2  // Distributed under the MIT software license, see the accompanying
   3  // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   4  
   5  #include <test/fuzz/FuzzedDataProvider.h>
   6  #include <test/fuzz/fuzz.h>
   7  #include <test/fuzz/util.h>
   8  #include <util/overflow.h>
   9  
  10  #include <cstdint>
  11  #include <string>
  12  #include <vector>
  13  
  14  namespace {
  15  template <typename T>
  16  void TestAdditionOverflow(FuzzedDataProvider& fuzzed_data_provider)
  17  {
  18      const T i = fuzzed_data_provider.ConsumeIntegral<T>();
  19      const T j = fuzzed_data_provider.ConsumeIntegral<T>();
  20      const bool is_addition_overflow_custom = AdditionOverflow(i, j);
  21      const auto maybe_add{CheckedAdd(i, j)};
  22      const auto sat_add{SaturatingAdd(i, j)};
  23      assert(is_addition_overflow_custom == !maybe_add.has_value());
  24      assert(is_addition_overflow_custom == AdditionOverflow(j, i));
  25      assert(maybe_add == CheckedAdd(j, i));
  26      assert(sat_add == SaturatingAdd(j, i));
  27  #ifndef _MSC_VER
  28      T result_builtin;
  29      const bool is_addition_overflow_builtin = __builtin_add_overflow(i, j, &result_builtin);
  30      assert(is_addition_overflow_custom == is_addition_overflow_builtin);
  31      if (!is_addition_overflow_custom) {
  32          assert(i + j == result_builtin);
  33      }
  34  #endif
  35      if (is_addition_overflow_custom) {
  36          assert(sat_add == std::numeric_limits<T>::min() || sat_add == std::numeric_limits<T>::max());
  37      } else {
  38          const auto add{i + j};
  39          assert(add == maybe_add.value());
  40          assert(add == sat_add);
  41      }
  42  }
  43  } // namespace
  44  
  45  FUZZ_TARGET(addition_overflow)
  46  {
  47      FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
  48      TestAdditionOverflow<int64_t>(fuzzed_data_provider);
  49      TestAdditionOverflow<uint64_t>(fuzzed_data_provider);
  50      TestAdditionOverflow<int32_t>(fuzzed_data_provider);
  51      TestAdditionOverflow<uint32_t>(fuzzed_data_provider);
  52      TestAdditionOverflow<int16_t>(fuzzed_data_provider);
  53      TestAdditionOverflow<uint16_t>(fuzzed_data_provider);
  54      TestAdditionOverflow<char>(fuzzed_data_provider);
  55      TestAdditionOverflow<unsigned char>(fuzzed_data_provider);
  56      TestAdditionOverflow<signed char>(fuzzed_data_provider);
  57  }
  58