Function Parse3NFA

extern/re2/re2/testing/regexp_benchmark.cc:1059–1072

// extracting three submatches.  Expects match always.

void Parse3NFA(benchmark::State& state, const char* regexp,
               const StringPiece& text) {
  for (auto _ : state) {
    Regexp* re = Regexp::Parse(regexp, Regexp::LikePerl, NULL);
    CHECK(re);
    Prog* prog = re->CompileToProg(0);
    CHECK(prog);
    StringPiece sp[4];  // 4 because sp[0] is whole match.
    CHECK(prog->SearchNFA(text, StringPiece(), Prog::kAnchored,
                          Prog::kFullMatch, sp, 4));
    delete prog;
    re->Decref();
  }
}

void Parse3OnePass(benchmark::State& state, const char* regexp,
                   const StringPiece& text) {