code_generator.h revision 9cf35523764d829ae0470dae2d5dd99be469c841 
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_OPTIMIZING_CODE_GENERATOR_H_
18#define ART_COMPILER_OPTIMIZING_CODE_GENERATOR_H_
19
20#include "base/bit_field.h"
21#include "globals.h"
22#include "instruction_set.h"
23#include "locations.h"
24#include "memory_region.h"
25#include "nodes.h"
26#include "utils/assembler.h"
27
28namespace art {
29
30static size_t constexpr kVRegSize = 4;
31static size_t constexpr kUninitializedFrameSize = 0;
32
33class DexCompilationUnit;
34
35class CodeAllocator {
36 public:
37  CodeAllocator() { }
38  virtual ~CodeAllocator() { }
39
40  virtual uint8_t* Allocate(size_t size) = 0;
41
42 private:
43  DISALLOW_COPY_AND_ASSIGN(CodeAllocator);
44};
45
46struct PcInfo {
47  uint32_t dex_pc;
48  uintptr_t native_pc;
49};
50
51class CodeGenerator : public ArenaObject {
52 public:
53  // Compiles the graph to executable instructions. Returns whether the compilation
54  // succeeded.
55  void CompileBaseline(CodeAllocator* allocator);
56  void CompileOptimized(CodeAllocator* allocator);
57  static CodeGenerator* Create(ArenaAllocator* allocator,
58                               HGraph* graph,
59                               InstructionSet instruction_set);
60
61  HGraph* GetGraph() const { return graph_; }
62
63  Label* GetLabelOf(HBasicBlock* block) const;
64  bool GoesToNextBlock(HBasicBlock* current, HBasicBlock* next) const;
65
66  size_t GetStackSlotOfParameter(HParameterValue* parameter) const {
67    // Note that this follows the current calling convention.
68    return GetFrameSize()
69        + kVRegSize  // Art method
70        + parameter->GetIndex() * kVRegSize;
71  }
72
73  virtual void GenerateFrameEntry() = 0;
74  virtual void GenerateFrameExit() = 0;
75  virtual void Bind(Label* label) = 0;
76  virtual void Move(HInstruction* instruction, Location location, HInstruction* move_for) = 0;
77  virtual HGraphVisitor* GetLocationBuilder() = 0;
78  virtual HGraphVisitor* GetInstructionVisitor() = 0;
79  virtual Assembler* GetAssembler() = 0;
80  virtual size_t GetWordSize() const = 0;
81  virtual void ComputeFrameSize(size_t number_of_spill_slots) = 0;
82
83  uint32_t GetFrameSize() const { return frame_size_; }
84  void SetFrameSize(uint32_t size) { frame_size_ = size; }
85  uint32_t GetCoreSpillMask() const { return core_spill_mask_; }
86
87  virtual size_t GetNumberOfCoreRegisters() const = 0;
88  virtual size_t GetNumberOfFloatingPointRegisters() const = 0;
89  virtual size_t GetNumberOfRegisters() const = 0;
90  virtual void SetupBlockedRegisters(bool* blocked_registers) const = 0;
91  virtual void DumpCoreRegister(std::ostream& stream, int reg) const = 0;
92  virtual void DumpFloatingPointRegister(std::ostream& stream, int reg) const = 0;
93
94  void RecordPcInfo(uint32_t dex_pc) {
95    struct PcInfo pc_info;
96    pc_info.dex_pc = dex_pc;
97    pc_info.native_pc = GetAssembler()->CodeSize();
98    pc_infos_.Add(pc_info);
99  }
100
101  void BuildMappingTable(std::vector<uint8_t>* vector) const;
102  void BuildVMapTable(std::vector<uint8_t>* vector) const;
103  void BuildNativeGCMap(
104      std::vector<uint8_t>* vector, const DexCompilationUnit& dex_compilation_unit) const;
105
106 protected:
107  CodeGenerator(HGraph* graph, size_t number_of_registers)
108      : frame_size_(kUninitializedFrameSize),
109        graph_(graph),
110        block_labels_(graph->GetArena(), 0),
111        pc_infos_(graph->GetArena(), 32),
112        blocked_registers_(graph->GetArena()->AllocArray<bool>(number_of_registers)) {}
113  ~CodeGenerator() {}
114
115  // Register allocation logic.
116  void AllocateRegistersLocally(HInstruction* instruction) const;
117
118  // Backend specific implementation for allocating a register.
119  virtual ManagedRegister AllocateFreeRegister(Primitive::Type type,
120                                               bool* blocked_registers) const = 0;
121
122  // Raw implementation of allocating a register: loops over blocked_registers to find
123  // the first available register.
124  size_t AllocateFreeRegisterInternal(bool* blocked_registers, size_t number_of_registers) const;
125
126  virtual Location GetStackLocation(HLoadLocal* load) const = 0;
127
128  // Frame size required for this method.
129  uint32_t frame_size_;
130  uint32_t core_spill_mask_;
131
132 private:
133  void InitLocations(HInstruction* instruction);
134
135  HGraph* const graph_;
136
137  // Labels for each block that will be compiled.
138  GrowableArray<Label> block_labels_;
139  GrowableArray<PcInfo> pc_infos_;
140
141  // Temporary data structure used when doing register allocation.
142  bool* const blocked_registers_;
143
144  DISALLOW_COPY_AND_ASSIGN(CodeGenerator);
145};
146
147template <typename T>
148class CallingConvention {
149 public:
150  CallingConvention(const T* registers, int number_of_registers)
151      : registers_(registers), number_of_registers_(number_of_registers) {}
152
153  size_t GetNumberOfRegisters() const { return number_of_registers_; }
154
155  T GetRegisterAt(size_t index) const {
156    DCHECK_LT(index, number_of_registers_);
157    return registers_[index];
158  }
159
160  uint8_t GetStackOffsetOf(size_t index) const {
161    // We still reserve the space for parameters passed by registers.
162    // Add one for the method pointer.
163    return (index + 1) * kVRegSize;
164  }
165
166 private:
167  const T* registers_;
168  const size_t number_of_registers_;
169
170  DISALLOW_COPY_AND_ASSIGN(CallingConvention);
171};
172
173}  // namespace art
174
175#endif  // ART_COMPILER_OPTIMIZING_CODE_GENERATOR_H_
176