1/*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17class SuperClass {
18}
19
20class ChildClass extends SuperClass {
21}
22
23public class Main {
24
25  public static void main(String[] args) {
26    test1();
27    test2();
28  }
29
30  /// CHECK-START:    void Main.test1() builder (after)
31  /// CHECK:          BoundType  klass:SuperClass can_be_null:false exact:false
32
33  /// CHECK-START:    void Main.test1() builder (after)
34  /// CHECK-NOT:      BoundType  klass:SuperClass can_be_null:false exact:true
35  public static void test1() {
36    Object obj = new ChildClass();
37
38    // We need a fixed point iteration to hit the bogus type update
39    // of 'obj' below, so create a loop that updates the type of 'obj'.
40    for (int i = 1; i < 1; i++) {
41      obj = new Object();
42    }
43
44    if (obj instanceof SuperClass) {
45      // We used to wrongly type obj as an exact SuperClass from this point,
46      // meaning we were statically determining that the following instanceof
47      // would always fail.
48      if (!(obj instanceof ChildClass)) {
49        throw new Error("Expected a ChildClass, got " + obj.getClass());
50      }
51    }
52  }
53
54  /// CHECK-START-X86: boolean Main.$noinline$instanceOfString(java.lang.Object) disassembly (after)
55  /// CHECK:          InstanceOf check_kind:exact_check
56  /// CHECK-NOT:      {{.*fs:.*}}
57
58  /// CHECK-START-X86_64: boolean Main.$noinline$instanceOfString(java.lang.Object) disassembly (after)
59  /// CHECK:          InstanceOf check_kind:exact_check
60  /// CHECK-NOT:      {{.*gs:.*}}
61
62  /// CHECK-START-{ARM,ARM64,MIPS,MIPS64}: boolean Main.$noinline$instanceOfString(java.lang.Object) disassembly (after)
63  /// CHECK:          InstanceOf check_kind:exact_check
64  // For ARM and ARM64, the marking register (r8 and x20, respectively) can be used in
65  // non-CC configs for any other purpose, so we'd need a config-specific checker test.
66  // TODO: Add the checks when we support config-specific tests.
67  public static boolean $noinline$instanceOfString(Object o) {
68    // String is a final class, so `instanceof String` should use exact check.
69    // String is in the boot image, so we should avoid read barriers. The presence
70    // of the read barrier can be checked in the architecture-specific disassembly.
71    return o instanceof String;
72  }
73
74  public static void test2() {
75    if ($noinline$instanceOfString(new Object())) {
76      throw new Error();
77    }
78    if (!$noinline$instanceOfString(new String())) {
79      throw new Error();
80    }
81  }
82}
83