1/*
2 * Copyright (C) 2014 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
17#include "gtest/gtest.h"
18#include "handle_scope-inl.h"
19#include "scoped_thread_state_change.h"
20#include "thread.h"
21
22namespace art {
23
24// Handle scope with a fixed size which is allocated on the stack.
25template<size_t kNumReferences>
26class NoThreadStackHandleScope : public HandleScope {
27 public:
28  explicit NoThreadStackHandleScope() : HandleScope(kNumReferences) {
29  }
30  ~NoThreadStackHandleScope() {
31  }
32
33 private:
34  // references_storage_ needs to be first so that it matches the address of references_
35  StackReference<mirror::Object> references_storage_[kNumReferences];
36};
37
38// Test the offsets computed for members of HandleScope. Because of cross-compiling
39// it is impossible the use OFFSETOF_MEMBER, so we do some reasonable computations ourselves. This
40// test checks whether we do the right thing.
41TEST(HandleScopeTest, Offsets) NO_THREAD_SAFETY_ANALYSIS {
42  // As the members of HandleScope are private, we cannot use OFFSETOF_MEMBER
43  // here. So do the inverse: set some data, and access it through pointers created from the offsets.
44  NoThreadStackHandleScope<1> test_table;
45  test_table.SetReference(0, reinterpret_cast<mirror::Object*>(0x1234));
46  test_table.SetLink(reinterpret_cast<HandleScope*>(0x5678));
47  test_table.SetNumberOfReferences(0x9ABC);
48
49  byte* table_base_ptr = reinterpret_cast<byte*>(&test_table);
50
51  {
52    uintptr_t* link_ptr = reinterpret_cast<uintptr_t*>(table_base_ptr +
53        HandleScope::LinkOffset(kPointerSize));
54    EXPECT_EQ(*link_ptr, static_cast<size_t>(0x5678));
55  }
56
57  {
58    uint32_t* num_ptr = reinterpret_cast<uint32_t*>(table_base_ptr +
59        HandleScope::NumberOfReferencesOffset(kPointerSize));
60    EXPECT_EQ(*num_ptr, static_cast<size_t>(0x9ABC));
61  }
62
63  {
64    // Assume sizeof(StackReference<mirror::Object>) == sizeof(uint32_t)
65    // TODO: How can we make this assumption-less but still access directly and fully?
66    EXPECT_EQ(sizeof(StackReference<mirror::Object>), sizeof(uint32_t));
67
68    uint32_t* ref_ptr = reinterpret_cast<uint32_t*>(table_base_ptr +
69        HandleScope::ReferencesOffset(kPointerSize));
70    EXPECT_EQ(*ref_ptr, static_cast<uint32_t>(0x1234));
71  }
72}
73
74}  // namespace art
75