Method loadUnit

lib/loader/loader.cpp:187–232

Load module or component unit. See "include/loader/loader.h".

// Load module or component unit. See "include/loader/loader.h".
Expect<std::variant<std::unique_ptr<AST::Component::Component>,
                    std::unique_ptr<AST::Module>>>
Loader::loadUnit() {
  EXPECTED_TRY(auto Preamble, loadPreamble());
  auto &[WasmMagic, Ver] = Preamble;
  if (Ver == ModuleVersion) {
    auto Mod = std::make_unique<AST::Module>();
    Mod->getMagic() = WasmMagic;
    Mod->getVersion() = Ver;
    if (Conf.getRuntimeConfigure().getRunMode() == RunMode::AOT) {
      EXPECTED_TRY(loadModuleAOT(Mod->getAOTSection()));
    }
    // Seek to the position after the binary header.
    FMgr.seek(8);
    EXPECTED_TRY(loadModule(*Mod));

    // Load library from AOT Section for the universal WASM case only when the
    // configured run mode is AOT.
    if (Conf.getRuntimeConfigure().getRunMode() == RunMode::AOT) {
      if (WASMType == InputType::UniversalWASM) {
        EXPECTED_TRY(loadUniversalWASM(*Mod));
      } else if (WASMType == InputType::WASM) {
        // AOT requested on a plain .wasm with no AOT artifact.
        spdlog::warn("AOT was requested but the input has no AOT artifact, "
                     "falling back to interpreter."sv);
      }
    }
    return Mod;
  } else if (Ver == ComponentVersion) {
    if (!Conf.hasProposal(Proposal::Component)) {
      return logNeedProposal(ErrCode::Value::MalformedVersion,
                             Proposal::Component, FMgr.getLastOffset(),
                             ASTNodeAttr::Component);
    }
    spdlog::warn("component model is an experimental proposal"sv);
    auto Comp = std::make_unique<AST::Component::Component>();
    Comp->getMagic() = WasmMagic;
    Comp->getVersion() = {Ver[0], Ver[1]};
    Comp->getLayer() = {Ver[2], Ver[3]};
    EXPECTED_TRY(loadComponent(*Comp));
    return Comp;
  } else {
    return logLoadError(ErrCode::Value::MalformedVersion, FMgr.getLastOffset(),
                        ASTNodeAttr::Component);
  }
}

// Serialize module into byte code. See "include/loader/loader.h".
Expect<std::vector<Byte>> Loader::serializeModule(const AST::Module &Mod) {