src/test/java/com/android/tools/r8/ir/regalloc/RedundantArgumentToPhiMoveIn16BitRegisterAllocationTest.java

// Copyright (c) 2024, 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.ir.regalloc;

import static com.android.tools.r8.utils.codeinspector.Matchers.isPresent;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.junit.Assert.assertTrue;

import com.android.tools.r8.TestBase;
import com.android.tools.r8.TestParameters;
import com.android.tools.r8.TestParametersCollection;
import com.android.tools.r8.utils.codeinspector.InstructionSubject;
import com.android.tools.r8.utils.codeinspector.MethodSubject;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.junit.runners.Parameterized;
import org.junit.runners.Parameterized.Parameter;
import org.junit.runners.Parameterized.Parameters;

@RunWith(Parameterized.class)
public class RedundantArgumentToPhiMoveIn16BitRegisterAllocationTest extends TestBase {

  @Parameter(0)
  public TestParameters parameters;

  @Parameters(name = "{0}")
  public static TestParametersCollection data() {
    return getTestParameters().withDefaultDexRuntime().withMaximumApiLevel().build();
  }

  @Test
  public void testD8() throws Exception {
    testForD8()
        .addInnerClasses(getClass())
        .release()
        .setMinApi(parameters)
        .compile()
        .inspect(
            inspector -> {
              MethodSubject testMethodSubject =
                  inspector.clazz(Main.class).uniqueMethodWithOriginalName("test");
              assertThat(testMethodSubject, isPresent());
              // TODO(b/374262806): We should not need to move the argument value to a local
              //  register. Instead, we should use the argument register for the phi and load the
              //  constant 42 into this register, thereby avoiding any moves.
              assertTrue(
                  testMethodSubject.streamInstructions().anyMatch(InstructionSubject::isMove));
            });
  }

  static class Main {

    static void test(
        long a, long b, long c, long d, long e, long f, long g, long h, long i, int def) {
      long j = (def & 1) == 0 ? i : 42;
      accept(j);
    }

    static void accept(long a) {}
  }
}