C++ JSScript::hasBaselineScript方法代码示例

EnterJitStatus js::jit::MaybeEnterJit(JSContext* cx, RunState& state) {
  JSScript* script = state.script();

  uint8_t* code = script->jitCodeRaw();
  do {
    // Make sure we have a BaselineScript: we don't want to call the
    // interpreter stub here. Note that Baseline code contains warm-up
    // checks in the prologue to Ion-compile if needed.
    if (script->hasBaselineScript()) {
      break;
    }

    // Try to Ion-compile.
    if (jit::IsIonEnabled(cx)) {
      jit::MethodStatus status = jit::CanEnterIon(cx, state);
      if (status == jit::Method_Error) {
        return EnterJitStatus::Error;
      }
      if (status == jit::Method_Compiled) {
        code = script->jitCodeRaw();
        break;
      }
    }

    // Try to Baseline-compile.
    if (jit::IsBaselineEnabled(cx)) {
      jit::MethodStatus status = jit::CanEnterBaselineMethod(cx, state);
      if (status == jit::Method_Error) {
        return EnterJitStatus::Error;
      }
      if (status == jit::Method_Compiled) {
        code = script->jitCodeRaw();
        break;
      }
    }

    return EnterJitStatus::NotEntered;
  } while (false);

  return EnterJit(cx, state, code);
}

bool
Module::callImport(JSContext* cx, uint32_t importIndex, unsigned argc, const Value* argv,
                   MutableHandleValue rval)
{
    MOZ_ASSERT(dynamicallyLinked_);

    const Import& import = imports()[importIndex];

    RootedValue fval(cx, ObjectValue(*importToExit(import).fun));
    if (!Invoke(cx, UndefinedValue(), fval, argc, argv, rval))
        return false;

    ImportExit& exit = importToExit(import);

    // The exit may already have become optimized.
    void* jitExitCode = code() + import.jitExitCodeOffset();
    if (exit.code == jitExitCode)
        return true;

    // Test if the function is JIT compiled.
    if (!exit.fun->hasScript())
        return true;
    JSScript* script = exit.fun->nonLazyScript();
    if (!script->hasBaselineScript()) {
        MOZ_ASSERT(!script->hasIonScript());
        return true;
    }

    // Don't enable jit entry when we have a pending ion builder.
    // Take the interpreter path which will link it and enable
    // the fast path on the next call.
    if (script->baselineScript()->hasPendingIonBuilder())
        return true;

    // Currently we can't rectify arguments. Therefore disable if argc is too low.
    if (exit.fun->nargs() > import.sig().args().length())
        return true;

    // Ensure the argument types are included in the argument TypeSets stored in
    // the TypeScript. This is necessary for Ion, because the import exit will
    // use the skip-arg-checks entry point.
    //
    // Note that the TypeScript is never discarded while the script has a
    // BaselineScript, so if those checks hold now they must hold at least until
    // the BaselineScript is discarded and when that happens the import exit is
    // patched back.
    if (!TypeScript::ThisTypes(script)->hasType(TypeSet::UndefinedType()))
        return true;
    for (uint32_t i = 0; i < exit.fun->nargs(); i++) {
        TypeSet::Type type = TypeSet::UnknownType();
        switch (import.sig().args()[i]) {
          case ValType::I32:   type = TypeSet::Int32Type(); break;
          case ValType::I64:   MOZ_CRASH("NYI");
          case ValType::F32:   type = TypeSet::DoubleType(); break;
          case ValType::F64:   type = TypeSet::DoubleType(); break;
          case ValType::I32x4: MOZ_CRASH("NYI");
          case ValType::F32x4: MOZ_CRASH("NYI");
          case ValType::B32x4: MOZ_CRASH("NYI");
          case ValType::Limit: MOZ_CRASH("Limit");
        }
        if (!TypeScript::ArgTypes(script, i)->hasType(type))
            return true;
    }

    // Let's optimize it!
    if (!script->baselineScript()->addDependentWasmModule(cx, *this, importIndex))
        return false;

    exit.code = jitExitCode;
    exit.baselineScript = script->baselineScript();
    return true;
}

bool
Instance::callImport(JSContext* cx, uint32_t funcImportIndex, unsigned argc, const uint64_t* argv,
                     MutableHandleValue rval)
{
    const FuncImport& fi = metadata().funcImports[funcImportIndex];

    InvokeArgs args(cx);
    if (!args.init(argc))
        return false;

    bool hasI64Arg = false;
    MOZ_ASSERT(fi.sig().args().length() == argc);
    for (size_t i = 0; i < argc; i++) {
        switch (fi.sig().args()[i]) {
          case ValType::I32:
            args[i].set(Int32Value(*(int32_t*)&argv[i]));
            break;
          case ValType::F32:
            args[i].set(JS::CanonicalizedDoubleValue(*(float*)&argv[i]));
            break;
          case ValType::F64:
            args[i].set(JS::CanonicalizedDoubleValue(*(double*)&argv[i]));
            break;
          case ValType::I64: {
            if (!JitOptions.wasmTestMode) {
                JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_WASM_BAD_I64);
                return false;
            }
            RootedObject obj(cx, CreateI64Object(cx, *(int64_t*)&argv[i]));
            if (!obj)
                return false;
            args[i].set(ObjectValue(*obj));
            hasI64Arg = true;
            break;
          }
          case ValType::I8x16:
          case ValType::I16x8:
          case ValType::I32x4:
          case ValType::F32x4:
          case ValType::B8x16:
          case ValType::B16x8:
          case ValType::B32x4:
          case ValType::Limit:
            MOZ_CRASH("unhandled type in callImport");
        }
    }

    FuncImportTls& import = funcImportTls(fi);
    RootedFunction importFun(cx, &import.obj->as<JSFunction>());
    RootedValue fval(cx, ObjectValue(*import.obj));
    RootedValue thisv(cx, UndefinedValue());
    if (!Call(cx, fval, thisv, args, rval))
        return false;

    // Throw an error if returning i64 and not in test mode.
    if (!JitOptions.wasmTestMode && fi.sig().ret() == ExprType::I64) {
        JS_ReportErrorNumber(cx, GetErrorMessage, nullptr, JSMSG_WASM_BAD_I64);
        return false;
    }

    // Don't try to optimize if the function has at least one i64 arg or if
    // it returns an int64. GenerateJitExit relies on this, as does the
    // type inference code below in this function.
    if (hasI64Arg || fi.sig().ret() == ExprType::I64)
        return true;

    // The import may already have become optimized.
    void* jitExitCode = codeBase() + fi.jitExitCodeOffset();
    if (import.code == jitExitCode)
        return true;

    // Test if the function is JIT compiled.
    if (!importFun->hasScript())
        return true;

    JSScript* script = importFun->nonLazyScript();
    if (!script->hasBaselineScript()) {
        MOZ_ASSERT(!script->hasIonScript());
        return true;
    }

    // Don't enable jit entry when we have a pending ion builder.
    // Take the interpreter path which will link it and enable
    // the fast path on the next call.
    if (script->baselineScript()->hasPendingIonBuilder())
        return true;

    // Currently we can't rectify arguments. Therefore disable if argc is too low.
    if (importFun->nargs() > fi.sig().args().length())
        return true;

    // Ensure the argument types are included in the argument TypeSets stored in
    // the TypeScript. This is necessary for Ion, because the import will use
    // the skip-arg-checks entry point.
    //
    // Note that the TypeScript is never discarded while the script has a
    // BaselineScript, so if those checks hold now they must hold at least until
    // the BaselineScript is discarded and when that happens the import is
    // patched back.
    if (!TypeScript::ThisTypes(script)->hasType(TypeSet::UndefinedType()))
//.........这里部分代码省略.........