Function parse_fn

tools/alive_parser.cpp:1364–1421

}

static void parse_fn(Function &f) {
  fn = &f;
  bb = &f.getBB("");
  bool has_return = false;

  while (true) {
    switch (auto t = *tokenizer) {
    case ASSUME:
      bb->addInstr(parse_assume());
      break;
    case LABEL:
      bb = &f.getBB(yylval.str);
      break;
    case RETURN: {
      auto instr = parse_return();
      f.setType(instr->getType());
      bb->addInstr(std::move(instr));
      has_return = true;
      break;
    }
    case UNREACH:
      bb->addInstr(make_unique<Assume>(get_constant(0, *int_types[1].get()),
                                       Assume::AndNonPoison));
      break;
    default:
      string_view name;
      if (t == REGISTER) {
        name = yylval.str;
        tokenizer.ensure(EQUALS);
      } else
        tokenizer.unget(t);

      auto i = parse_instr(name);
      if (!i) {
        if (name.empty())
          goto exit;
        error("Instruction expected", *tokenizer);
      }

      if (!name.empty()) {
        if (!identifiers.emplace(name, i.get()).second)
          error("Duplicated assignment to " + string(name));
      }
      bb->addInstr(std::move(i));
      break;
    }
  }

exit:
  if (!has_return) {
    if (bb->empty())
      error("Block cannot be empty");

    auto &val = bb->back();
    bb->addInstr(make_unique<Return>(val.getType(), val));
    f.setType(val.getType());
  }
}