1/*
2 * Copyright (C) 2013 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 <algorithm>
18#include <utility>
19#include "thread.h"
20#include "thread-inl.h"
21#include "base/mutex.h"
22#include "base/mutex-inl.h"
23#include "base/logging.h"
24#include "driver/compiler_driver.h"
25
26#include "dex_file_to_method_inliner_map.h"
27
28namespace art {
29
30DexFileToMethodInlinerMap::DexFileToMethodInlinerMap()
31    : lock_("DexFileToMethodInlinerMap lock", kDexFileToMethodInlinerMapLock) {
32}
33
34DexFileToMethodInlinerMap::~DexFileToMethodInlinerMap() {
35  for (auto& entry : inliners_) {
36    delete entry.second;
37  }
38}
39
40DexFileMethodInliner* DexFileToMethodInlinerMap::GetMethodInliner(const DexFile* dex_file) {
41  Thread* self = Thread::Current();
42  {
43    ReaderMutexLock mu(self, lock_);
44    auto it = inliners_.find(dex_file);
45    if (it != inliners_.end()) {
46      return it->second;
47    }
48  }
49
50  // We need to acquire our lock_ to modify inliners_ but we want to release it
51  // before we initialize the new inliner. However, we need to acquire the
52  // new inliner's lock_ before we release our lock_ to prevent another thread
53  // from using the uninitialized inliner. This requires explicit calls to
54  // ExclusiveLock()/ExclusiveUnlock() on one of the locks, the other one
55  // can use WriterMutexLock.
56  DexFileMethodInliner* locked_inliner;
57  {
58    WriterMutexLock mu(self, lock_);
59    DexFileMethodInliner** inliner = &inliners_[dex_file];  // inserts new entry if not found
60    if (*inliner) {
61      return *inliner;
62    }
63    *inliner = new DexFileMethodInliner;
64    DCHECK(*inliner != nullptr);
65    locked_inliner = *inliner;
66    locked_inliner->lock_.ExclusiveLock(self);  // Acquire inliner's lock_ before releasing lock_.
67  }
68  locked_inliner->FindIntrinsics(dex_file);
69  locked_inliner->lock_.ExclusiveUnlock(self);
70  return locked_inliner;
71}
72
73}  // namespace art
74