instruction_flags.h revision 834b394ee759ed31c5371d8093d7cd8cd90014a8 
1/*
2 * Copyright (C) 2011 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_RUNTIME_VERIFIER_INSTRUCTION_FLAGS_H_
18#define ART_RUNTIME_VERIFIER_INSTRUCTION_FLAGS_H_
19
20#include "base/logging.h"
21
22#include <stdint.h>
23#include <string>
24
25namespace art {
26namespace verifier {
27
28class InstructionFlags {
29 public:
30  InstructionFlags() : length_(0), flags_(0) {}
31
32  void SetLengthInCodeUnits(size_t length) {
33    DCHECK_LT(length, 65536u);
34    length_ = length;
35  }
36  size_t GetLengthInCodeUnits() {
37    return length_;
38  }
39  bool IsOpcode() const {
40    return length_ != 0;
41  }
42
43  void SetInTry() {
44    flags_ |= 1 << kInTry;
45  }
46  void ClearInTry() {
47    flags_ &= ~(1 << kInTry);
48  }
49  bool IsInTry() const {
50    return (flags_ & (1 << kInTry)) != 0;
51  }
52
53  void SetBranchTarget() {
54    flags_ |= 1 << kBranchTarget;
55  }
56  void ClearBranchTarget() {
57    flags_ &= ~(1 << kBranchTarget);
58  }
59  bool IsBranchTarget() const {
60    return (flags_ & (1 << kBranchTarget)) != 0;
61  }
62  void SetCompileTimeInfoPoint() {
63    flags_ |= 1 << kCompileTimeInfoPoint;
64  }
65  void ClearCompileTimeInfoPoint() {
66    flags_ &= ~(1 << kCompileTimeInfoPoint);
67  }
68  bool IsCompileTimeInfoPoint() const {
69    return (flags_ & (1 << kCompileTimeInfoPoint)) != 0;
70  }
71
72  void SetVisited() {
73    flags_ |= 1 << kVisited;
74  }
75  void ClearVisited() {
76    flags_ &= ~(1 << kVisited);
77  }
78  bool IsVisited() const {
79    return (flags_ & (1 << kVisited)) != 0;
80  }
81
82  void SetChanged() {
83    flags_ |= 1 << kChanged;
84  }
85  void ClearChanged() {
86    flags_ &= ~(1 << kChanged);
87  }
88  bool IsChanged() const {
89    return (flags_ & (1 << kChanged)) != 0;
90  }
91
92  bool IsVisitedOrChanged() const {
93    return IsVisited() || IsChanged();
94  }
95
96  void SetReturn() {
97    flags_ |= 1 << kReturn;
98  }
99  void ClearReturn() {
100    flags_ &= ~(1 << kReturn);
101  }
102  bool IsReturn() const {
103    return (flags_ & (1 << kReturn)) != 0;
104  }
105
106  void SetCompileTimeInfoPointAndReturn() {
107    SetCompileTimeInfoPoint();
108    SetReturn();
109  }
110
111  std::string ToString() const;
112
113 private:
114  enum {
115    // The instruction has been visited and unless IsChanged() verified.
116    kVisited = 0,
117    // Register type information flowing into the instruction changed and so the instruction must be
118    // reprocessed.
119    kChanged = 1,
120    // Instruction is contained within a try region.
121    kInTry = 2,
122    // Instruction is the target of a branch (ie the start of a basic block).
123    kBranchTarget = 3,
124    // Location of interest to the compiler for GC maps and verifier based method sharpening.
125    kCompileTimeInfoPoint = 4,
126    // A return instruction.
127    kReturn = 5,
128  };
129
130  // Size of instruction in code units.
131  uint16_t length_;
132  uint8_t flags_;
133};
134
135}  // namespace verifier
136}  // namespace art
137
138#endif  // ART_RUNTIME_VERIFIER_INSTRUCTION_FLAGS_H_
139