src/test/java/com/android/tools/r8/enumunboxing/enummerging/DeterministicEnumMergingTest.java

// Copyright (c) 2023, the R8 project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.
package com.android.tools.r8.enumunboxing.enummerging;

import com.android.tools.r8.NeverInline;
import com.android.tools.r8.R8TestCompileResult;
import com.android.tools.r8.TestParameters;
import com.android.tools.r8.enumunboxing.EnumUnboxingTestBase;
import java.util.List;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameters;

@RunWith(Parameterized.class)
public class DeterministicEnumMergingTest extends EnumUnboxingTestBase {

  private final TestParameters parameters;
  private final boolean enumValueOptimization;
  private final EnumKeepRules enumKeepRules;

  @Parameters(name = "{0} valueOpt: {1} keep: {2}")
  public static List<Object[]> data() {
    return enumUnboxingTestParameters();
  }

  public DeterministicEnumMergingTest(
      TestParameters parameters, boolean enumValueOptimization, EnumKeepRules enumKeepRules) {
    this.parameters = parameters;
    this.enumValueOptimization = enumValueOptimization;
    this.enumKeepRules = enumKeepRules;
  }

  @Test
  public void testEnumUnboxingDeterminism() throws Exception {
    R8TestCompileResult compile1 =
        testForR8(parameters.getBackend())
            .addInnerClasses(getClass())
            .addKeepMainRule(Main.class)
            .addKeepRules(enumKeepRules.getKeepRules())
            .addEnumUnboxingInspector(inspector -> inspector.assertUnboxed(MyEnum.class))
            .enableInliningAnnotations()
            .addOptionsModification(opt -> enableEnumOptions(opt, enumValueOptimization))
            .setMinApi(parameters)
            .compile();
    R8TestCompileResult compile2 =
        testForR8(parameters.getBackend())
            .addInnerClasses(getClass())
            .addKeepMainRule(Main.class)
            .addKeepRules(enumKeepRules.getKeepRules())
            .addEnumUnboxingInspector(inspector -> inspector.assertUnboxed(MyEnum.class))
            .enableInliningAnnotations()
            .addOptionsModification(opt -> enableEnumOptions(opt, enumValueOptimization))
            .setMinApi(parameters)
            .compile();
    assertIdenticalInspectors(compile1.inspector(), compile2.inspector());
    compile1
        .run(parameters.getRuntime(), Main.class)
        .assertSuccessWithOutputLines("336", "74", "22", "10794", "96", "44", "52", "3084");
  }

  enum MyEnum {
    // The more cases, the highest the chance to trigger non determinism.
    // The operate methods have to be moved in the same order, and the dispatch method has to
    // be generated in the same order too.
    A(8) {
      @NeverInline
      @Override
      public long operate(long another) {
        return num * another;
      }
    },
    B(32) {
      @NeverInline
      @Override
      public long operate(long another) {
        return num + another;
      }
    },
    C(64) {
      @NeverInline
      @Override
      public long operate(long another) {
        return num - another;
      }
    },
    D(256) {

      @NeverInline
      @Override
      public long operate(long another) {
        return num * another + another;
      }
    };
    final long num;

    MyEnum(long num) {
      this.num = num;
    }

    public abstract long operate(long another);
  }

  static class Main {

    public static void main(String[] args) {
      System.out.println(MyEnum.A.operate(42));
      System.out.println(MyEnum.B.operate(42));
      System.out.println(MyEnum.C.operate(42));
      System.out.println(MyEnum.D.operate(42));
      System.out.println(indirect(MyEnum.A));
      System.out.println(indirect(MyEnum.B));
      System.out.println(indirect(MyEnum.C));
      System.out.println(indirect(MyEnum.D));
    }

    @NeverInline
    public static long indirect(MyEnum e) {
      return e.operate(12);
    }
  }
}