float.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 <memusage.h>
   6  #include <test/fuzz/FuzzedDataProvider.h>
   7  #include <test/fuzz/fuzz.h>
   8  #include <test/fuzz/util.h>
   9  #include <util/serfloat.h>
  10  
  11  #include <cassert>
  12  #include <cmath>
  13  #include <limits>
  14  #include <optional>
  15  
  16  FUZZ_TARGET(float)
  17  {
  18      FuzzedDataProvider fuzzed_data_provider(buffer.data(), buffer.size());
  19  
  20      {
  21          const double d{[&] {
  22              std::optional<double> tmp;
  23              CallOneOf(
  24                  fuzzed_data_provider,
  25                  // an actual number
  26                  [&] { tmp = fuzzed_data_provider.ConsumeFloatingPoint<double>(); },
  27                  // special numbers and NANs
  28                  [&] { tmp = fuzzed_data_provider.PickValueInArray({
  29                            std::numeric_limits<double>::infinity(),
  30                            -std::numeric_limits<double>::infinity(),
  31                            std::numeric_limits<double>::min(),
  32                            -std::numeric_limits<double>::min(),
  33                            std::numeric_limits<double>::max(),
  34                            -std::numeric_limits<double>::max(),
  35                            std::numeric_limits<double>::lowest(),
  36                            -std::numeric_limits<double>::lowest(),
  37                            std::numeric_limits<double>::quiet_NaN(),
  38                            -std::numeric_limits<double>::quiet_NaN(),
  39                            std::numeric_limits<double>::signaling_NaN(),
  40                            -std::numeric_limits<double>::signaling_NaN(),
  41                            std::numeric_limits<double>::denorm_min(),
  42                            -std::numeric_limits<double>::denorm_min(),
  43                        }); },
  44                  // Anything from raw memory (also checks that DecodeDouble doesn't crash on any input)
  45                  [&] { tmp = DecodeDouble(fuzzed_data_provider.ConsumeIntegral<uint64_t>()); });
  46              return *tmp;
  47          }()};
  48          (void)memusage::DynamicUsage(d);
  49  
  50          uint64_t encoded = EncodeDouble(d);
  51          if constexpr (std::numeric_limits<double>::is_iec559) {
  52              if (!std::isnan(d)) {
  53                  uint64_t encoded_in_memory;
  54                  std::copy((const unsigned char*)&d, (const unsigned char*)(&d + 1), (unsigned char*)&encoded_in_memory);
  55                  assert(encoded_in_memory == encoded);
  56              }
  57          }
  58          double d_deserialized = DecodeDouble(encoded);
  59          assert(std::isnan(d) == std::isnan(d_deserialized));
  60          assert(std::isnan(d) || d == d_deserialized);
  61      }
  62  }
  63