reference_type_propagation.h revision 8b3f9b246d5bdbf67faeb2b872b75b8d72777bc0 
1/*
2 * Copyright (C) 2015 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#ifndef ART_COMPILER_OPTIMIZING_REFERENCE_TYPE_PROPAGATION_H_
18#define ART_COMPILER_OPTIMIZING_REFERENCE_TYPE_PROPAGATION_H_
19
20#include "base/arena_containers.h"
21#include "driver/dex_compilation_unit.h"
22#include "handle_scope-inl.h"
23#include "nodes.h"
24#include "optimization.h"
25#include "optimizing_compiler_stats.h"
26
27namespace art {
28
29/**
30 * Propagates reference types to instructions.
31 */
32class ReferenceTypePropagation : public HOptimization {
33 public:
34  ReferenceTypePropagation(HGraph* graph,
35                           StackHandleScopeCollection* handles,
36                           bool is_first_run,
37                           const char* name = kReferenceTypePropagationPassName);
38
39  // Visit a single instruction.
40  void Visit(HInstruction* instruction);
41
42  void Run() OVERRIDE;
43
44  static constexpr const char* kReferenceTypePropagationPassName = "reference_type_propagation";
45
46 private:
47  class HandleCache {
48   public:
49    explicit HandleCache(StackHandleScopeCollection* handles) : handles_(handles) { }
50
51    template <typename T>
52    MutableHandle<T> NewHandle(T* object) SHARED_REQUIRES(Locks::mutator_lock_) {
53      return handles_->NewHandle(object);
54    }
55
56    ReferenceTypeInfo::TypeHandle GetObjectClassHandle();
57    ReferenceTypeInfo::TypeHandle GetClassClassHandle();
58    ReferenceTypeInfo::TypeHandle GetStringClassHandle();
59    ReferenceTypeInfo::TypeHandle GetThrowableClassHandle();
60
61   private:
62    StackHandleScopeCollection* handles_;
63
64    ReferenceTypeInfo::TypeHandle object_class_handle_;
65    ReferenceTypeInfo::TypeHandle class_class_handle_;
66    ReferenceTypeInfo::TypeHandle string_class_handle_;
67    ReferenceTypeInfo::TypeHandle throwable_class_handle_;
68  };
69
70  class RTPVisitor;
71
72  void VisitPhi(HPhi* phi);
73  void VisitBasicBlock(HBasicBlock* block);
74  void UpdateBoundType(HBoundType* bound_type) SHARED_REQUIRES(Locks::mutator_lock_);
75  void UpdatePhi(HPhi* phi) SHARED_REQUIRES(Locks::mutator_lock_);
76  void BoundTypeForIfNotNull(HBasicBlock* block);
77  void BoundTypeForIfInstanceOf(HBasicBlock* block);
78  void ProcessWorklist();
79  void AddToWorklist(HInstruction* instr);
80  void AddDependentInstructionsToWorklist(HInstruction* instr);
81
82  bool UpdateNullability(HInstruction* instr);
83  bool UpdateReferenceTypeInfo(HInstruction* instr);
84
85  static void UpdateArrayGet(HArrayGet* instr, HandleCache* handle_cache)
86      SHARED_REQUIRES(Locks::mutator_lock_);
87
88  ReferenceTypeInfo MergeTypes(const ReferenceTypeInfo& a, const ReferenceTypeInfo& b)
89      SHARED_REQUIRES(Locks::mutator_lock_);
90
91  void ValidateTypes();
92
93  HandleCache handle_cache_;
94
95  ArenaVector<HInstruction*> worklist_;
96
97  // Whether this reference type propagation is the first run we are doing.
98  const bool is_first_run_;
99
100  static constexpr size_t kDefaultWorklistSize = 8;
101
102  friend class ReferenceTypePropagationTest;
103
104  DISALLOW_COPY_AND_ASSIGN(ReferenceTypePropagation);
105};
106
107}  // namespace art
108
109#endif  // ART_COMPILER_OPTIMIZING_REFERENCE_TYPE_PROPAGATION_H_
110