Method BestEffortMatchFunctions

source/diff/diff.cpp:1655–1720

}

void Differ::BestEffortMatchFunctions(const IdGroup& src_func_ids,
                                      const IdGroup& dst_func_ids,
                                      const FunctionInstMap& src_func_insts,
                                      const FunctionInstMap& dst_func_insts) {
  struct MatchResult {
    uint32_t src_id;
    uint32_t dst_id;
    DiffMatch src_match;
    DiffMatch dst_match;
    float match_rate;
    bool operator<(const MatchResult& other) const {
      return match_rate > other.match_rate;
    }
  };
  std::vector<MatchResult> all_match_results;

  for (const uint32_t src_func_id : src_func_ids) {
    if (id_map_.IsSrcMapped(src_func_id)) {
      continue;
    }
    const std::string src_name = GetSanitizedName(src_id_to_, src_func_id);

    for (const uint32_t dst_func_id : dst_func_ids) {
      if (id_map_.IsDstMapped(dst_func_id)) {
        continue;
      }

      // Don't match functions that are named, but the names are different.
      const std::string dst_name = GetSanitizedName(dst_id_to_, dst_func_id);
      if (src_name != "" && dst_name != "" && src_name != dst_name) {
        continue;
      }

      DiffMatch src_match_result, dst_match_result;
      float match_rate = MatchFunctionBodies(
          src_func_insts.at(src_func_id), dst_func_insts.at(dst_func_id),
          &src_match_result, &dst_match_result);

      // Only consider the functions a match if there's at least 60% match.
      // This is an arbitrary limit that should be tuned.
      constexpr float pass_match_rate = 0.6f;
      if (match_rate >= pass_match_rate) {
        all_match_results.emplace_back(
            MatchResult{src_func_id, dst_func_id, std::move(src_match_result),
                        std::move(dst_match_result), match_rate});
      }
    }
  }

  std::sort(all_match_results.begin(), all_match_results.end());

  for (const MatchResult& match_result : all_match_results) {
    if (id_map_.IsSrcMapped(match_result.src_id) ||
        id_map_.IsDstMapped(match_result.dst_id)) {
      continue;
    }

    id_map_.MapIds(match_result.src_id, match_result.dst_id);