content: /*
   * Copyright (C) 2017 The Android Open Source Project
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  abstract class Base {
    abstract void foo(int i);
  
    void printError(String msg) {
      System.out.println(msg);
    }
  }
  
  class Main1 extends Base {
    void foo(int i) {
      if (i != 1) {
        printError("error1");
      }
    }
  }
  
  class Main2 extends Main1 {
    void foo(int i) {
      if (i != 2) {
        printError("error2");
      }
    }
  }
  
  public class Main {
    static Base sMain1;
    static Base sMain2;
  
    static boolean sIsOptimizing = true;
    static boolean sHasJIT = true;
    static volatile boolean sOtherThreadStarted;
  
    private static void assertSingleImplementation(Class<?> clazz, String method_name, boolean b) {
      if (hasSingleImplementation(clazz, method_name) != b) {
        System.out.println(clazz + "." + method_name +
            " doesn't have single implementation value of " + b);
      }
    }
  
    // sMain1.foo() will be always be Main1.foo() before Main2 is loaded/linked.
    // So sMain1.foo() can be devirtualized to Main1.foo() and be inlined.
    // After Dummy.createMain2() which links in Main2, live testOverride() on stack
    // should be deoptimized.
    static void testOverride(boolean createMain2, boolean wait, boolean setHasJIT) {
      if (setHasJIT) {
        if (isInterpreted()) {
          sHasJIT = false;
        }
        return;
      }
  
      if (createMain2 && (sIsOptimizing || sHasJIT)) {
        assertIsManaged();
      }
  
      sMain1.foo(sMain1.getClass() == Main1.class ? 1 : 2);
  
      if (createMain2) {
        // Wait for the other thread to start.
        while (!sOtherThreadStarted);
        // Create an Main2 instance and assign it to sMain2.
        // sMain1 is kept the same.
        sMain2 = Dummy.createMain2();
        // Wake up the other thread.
        synchronized(Main.class) {
          Main.class.notify();
        }
      } else if (wait) {
        // This is the other thread.
        synchronized(Main.class) {
          sOtherThreadStarted = true;
          // Wait for Main2 to be linked and deoptimization is triggered.
          try {
            Main.class.wait();
          } catch (Exception e) {
          }
        }
      }
  
      // There should be a deoptimization here right after Main2 is linked by
      // calling Dummy.createMain2(), even though sMain1 didn't change.
      // The behavior here would be different if inline-cache is used, which
      // doesn't deoptimize since sMain1 still hits the type cache.
      sMain1.foo(sMain1.getClass() == Main1.class ? 1 : 2);
      if ((createMain2 || wait) && sHasJIT && !sIsOptimizing) {
        // This method should be deoptimized right after Main2 is created.
        assertIsInterpreted();
      }
  
      if (sMain2 != null) {
        sMain2.foo(sMain2.getClass() == Main1.class ? 1 : 2);
      }
    }
  
    // Test scenarios under which CHA-based devirtualization happens,
    // and class loading that overrides a method can invalidate compiled code.
    public static void main(String[] args) {
      System.loadLibrary(args[0]);
  
      if (isInterpreted()) {
        sIsOptimizing = false;
      }
  
      // sMain1 is an instance of Main1. Main2 hasn't bee loaded yet.
      sMain1 = new Main1();
  
      ensureJitCompiled(Main.class, "testOverride");
      testOverride(false, false, true);
  
      if (sHasJIT && !sIsOptimizing) {
        assertSingleImplementation(Base.class, "foo", true);
        assertSingleImplementation(Main1.class, "foo", true);
      } else {
        // Main2 is verified ahead-of-time so it's linked in already.
      }
  
      // Create another thread that also calls sMain1.foo().
      // Try to test suspend and deopt another thread.
      new Thread() {
        public void run() {
          testOverride(false, true, false);
        }
      }.start();
  
      // This will create Main2 instance in the middle of testOverride().
      testOverride(true, false, false);
      assertSingleImplementation(Base.class, "foo", false);
      assertSingleImplementation(Main1.class, "foo", false);
    }
  
    private static native void ensureJitCompiled(Class<?> itf, String method_name);
    private static native void assertIsInterpreted();
    private static native void assertIsManaged();
    private static native boolean isInterpreted();
    private static native boolean hasSingleImplementation(Class<?> clazz, String method_name);
  }
  
  // Put createMain2() in another class to avoid class loading due to verifier.
  class Dummy {
    static Main1 createMain2() {
      return new Main2();
    }
  }
  