test/2251-checker-irreducible-loop-do-not-inline/src/Main.java

/*
 * Copyright (C) 2022 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.
 */

import java.lang.reflect.Method;

public class Main {
    public static void main(String[] args) throws Exception {
        Object[] arguments = {new Object()};
        Object result = Class.forName("IrreducibleLoop")
                                .getMethod("testDoNotInlineInner", Object.class)
                                .invoke(null, arguments);
        if (result == null) {
            throw new Exception("Expected non-null result");
        }
    }

    // Simple method to have a call inside of the synchronized block.
    private static Object $noinline$call() {
        return new Object();
    }

    // `inner` has a Return -> TryBoundary -> Exit chain, which means that when we inline it we
    // would need to recompute the loop information.

    // Consistency check: Three try boundary kind:exit. One for the explicit try catch, and two for
    // the synchronized block (normal, and exceptional path).

    /// CHECK-START: java.lang.Object Main.inner(java.lang.Object) builder (after)
    /// CHECK:     TryBoundary kind:exit
    /// CHECK:     TryBoundary kind:exit
    /// CHECK:     TryBoundary kind:exit
    /// CHECK-NOT: TryBoundary kind:exit

    /// CHECK-START: java.lang.Object Main.inner(java.lang.Object) builder (after)
    /// CHECK: Return loop:B2

    /// CHECK-START: java.lang.Object Main.inner(java.lang.Object) builder (after)
    /// CHECK: TryBoundary kind:exit loop:B2
    /// CHECK: TryBoundary kind:exit loop:B2
    /// CHECK: TryBoundary kind:exit loop:B2
    public static Object inner(Object o) {
        for (int i = 0; i < 4; i++) {
            try {
                synchronized (o) {
                    return $noinline$call();
                }
            } catch (Error e) {
                continue;
            }
        }
        return null;
    }
}