pass.h revision 4f59668b3d51f63601ebe59dbd2b7e8a7c5bd093 
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#ifndef ART_COMPILER_DEX_PASS_H_
18#define ART_COMPILER_DEX_PASS_H_
19
20#include <string>
21
22#include "base/macros.h"
23namespace art {
24
25// Empty Pass Data Class, can be extended by any pass extending the base Pass class.
26class PassDataHolder {
27};
28
29/**
30 * @class Pass
31 * @brief Base Pass class, can be extended to perform a more defined way of doing the work call.
32 */
33class Pass {
34 public:
35  explicit Pass(const char* name)
36    : pass_name_(name) {
37  }
38
39  virtual ~Pass() {
40  }
41
42  virtual const char* GetName() const {
43    return pass_name_;
44  }
45
46  /**
47   * @brief Gate for the pass: determines whether to execute the pass or not considering a CompilationUnit
48   * @param data the PassDataHolder.
49   * @return whether or not to execute the pass.
50   */
51  virtual bool Gate(const PassDataHolder* data) const {
52    // Unused parameter.
53    UNUSED(data);
54
55    // Base class says yes.
56    return true;
57  }
58
59  /**
60   * @brief Start of the pass: called before the Worker function.
61   */
62  virtual void Start(const PassDataHolder* data) const {
63    // Unused parameter.
64    UNUSED(data);
65  }
66
67  /**
68   * @brief End of the pass: called after the WalkBasicBlocks function.
69   */
70  virtual void End(const PassDataHolder* data) const {
71    // Unused parameter.
72    UNUSED(data);
73  }
74
75  /**
76   * @param data the object containing data necessary for the pass.
77   * @return whether or not there is a change when walking the BasicBlock
78   */
79  virtual bool Worker(const PassDataHolder* data) const {
80    // Unused parameter.
81    UNUSED(data);
82
83    // BasicBlock did not change.
84    return false;
85  }
86
87 protected:
88  /** @brief The pass name: used for searching for a pass when running a particular pass or debugging. */
89  const char* const pass_name_;
90
91 private:
92  // In order to make the all passes not copy-friendly.
93  DISALLOW_COPY_AND_ASSIGN(Pass);
94};
95}  // namespace art
96#endif  // ART_COMPILER_DEX_PASS_H_
97