optimizing_compiler.cc revision 8d486731559ba0c5e12c27b4a507181333702b7e 
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#include <fstream>
18#include <stdint.h>
19
20#include "builder.h"
21#include "code_generator.h"
22#include "compilers.h"
23#include "driver/compiler_driver.h"
24#include "driver/dex_compilation_unit.h"
25#include "graph_visualizer.h"
26#include "nodes.h"
27#include "register_allocator.h"
28#include "ssa_phi_elimination.h"
29#include "ssa_liveness_analysis.h"
30#include "utils/arena_allocator.h"
31
32namespace art {
33
34/**
35 * Used by the code generator, to allocate the code in a vector.
36 */
37class CodeVectorAllocator FINAL : public CodeAllocator {
38 public:
39  CodeVectorAllocator() { }
40
41  virtual uint8_t* Allocate(size_t size) {
42    size_ = size;
43    memory_.resize(size);
44    return &memory_[0];
45  }
46
47  size_t GetSize() const { return size_; }
48  const std::vector<uint8_t>& GetMemory() const { return memory_; }
49
50 private:
51  std::vector<uint8_t> memory_;
52  size_t size_;
53
54  DISALLOW_COPY_AND_ASSIGN(CodeVectorAllocator);
55};
56
57/**
58 * If set to true, generates a file suitable for the c1visualizer tool and IRHydra.
59 */
60static bool kIsVisualizerEnabled = false;
61
62/**
63 * Filter to apply to the visualizer. Methods whose name contain that filter will
64 * be in the file.
65 */
66static const char* kStringFilter = "";
67
68OptimizingCompiler::OptimizingCompiler(CompilerDriver* driver) : QuickCompiler(driver) {
69  if (kIsVisualizerEnabled) {
70    visualizer_output_.reset(new std::ofstream("art.cfg"));
71  }
72}
73
74CompiledMethod* OptimizingCompiler::TryCompile(const DexFile::CodeItem* code_item,
75                                               uint32_t access_flags,
76                                               InvokeType invoke_type,
77                                               uint16_t class_def_idx,
78                                               uint32_t method_idx,
79                                               jobject class_loader,
80                                               const DexFile& dex_file) const {
81  InstructionSet instruction_set = GetCompilerDriver()->GetInstructionSet();
82  // Always use the thumb2 assembler: some runtime functionality (like implicit stack
83  // overflow checks) assume thumb2.
84  if (instruction_set == kArm) {
85    instruction_set = kThumb2;
86  }
87
88  // Do not attempt to compile on architectures we do not support.
89  if (instruction_set != kX86 && instruction_set != kX86_64 && instruction_set != kThumb2) {
90    return nullptr;
91  }
92
93  DexCompilationUnit dex_compilation_unit(
94    nullptr, class_loader, art::Runtime::Current()->GetClassLinker(), dex_file, code_item,
95    class_def_idx, method_idx, access_flags,
96    GetCompilerDriver()->GetVerifiedMethod(&dex_file, method_idx));
97
98  // For testing purposes, we put a special marker on method names that should be compiled
99  // with this compiler. This makes sure we're not regressing.
100  bool shouldCompile = dex_compilation_unit.GetSymbol().find("00024opt_00024") != std::string::npos;
101  bool shouldOptimize =
102      dex_compilation_unit.GetSymbol().find("00024reg_00024") != std::string::npos;
103
104  ArenaPool pool;
105  ArenaAllocator arena(&pool);
106  HGraphBuilder builder(&arena, &dex_compilation_unit, &dex_file, GetCompilerDriver());
107
108  HGraph* graph = builder.BuildGraph(*code_item);
109  if (graph == nullptr) {
110    if (shouldCompile) {
111      LOG(FATAL) << "Could not build graph in optimizing compiler";
112    }
113    return nullptr;
114  }
115
116  CodeGenerator* codegen = CodeGenerator::Create(&arena, graph, instruction_set);
117  if (codegen == nullptr) {
118    if (shouldCompile) {
119      LOG(FATAL) << "Could not find code generator for optimizing compiler";
120    }
121    return nullptr;
122  }
123
124  HGraphVisualizer visualizer(
125      visualizer_output_.get(), graph, kStringFilter, *codegen, dex_compilation_unit);
126  visualizer.DumpGraph("builder");
127
128  CodeVectorAllocator allocator;
129
130  if (RegisterAllocator::CanAllocateRegistersFor(*graph, instruction_set)) {
131    graph->BuildDominatorTree();
132    graph->TransformToSSA();
133    visualizer.DumpGraph("ssa");
134    graph->FindNaturalLoops();
135
136    SsaRedundantPhiElimination(graph).Run();
137    SsaDeadPhiElimination(graph).Run();
138
139    SsaLivenessAnalysis liveness(*graph, codegen);
140    liveness.Analyze();
141    visualizer.DumpGraph(kLivenessPassName);
142
143    RegisterAllocator register_allocator(graph->GetArena(), codegen, liveness);
144    register_allocator.AllocateRegisters();
145
146    visualizer.DumpGraph(kRegisterAllocatorPassName);
147    codegen->CompileOptimized(&allocator);
148  } else if (shouldOptimize && RegisterAllocator::Supports(instruction_set)) {
149    LOG(FATAL) << "Could not allocate registers in optimizing compiler";
150  } else {
151    codegen->CompileBaseline(&allocator);
152
153    // Run these phases to get some test coverage.
154    graph->BuildDominatorTree();
155    graph->TransformToSSA();
156    visualizer.DumpGraph("ssa");
157    graph->FindNaturalLoops();
158    SsaLivenessAnalysis liveness(*graph, codegen);
159    liveness.Analyze();
160    visualizer.DumpGraph(kLivenessPassName);
161  }
162
163  std::vector<uint8_t> mapping_table;
164  codegen->BuildMappingTable(&mapping_table);
165  std::vector<uint8_t> vmap_table;
166  codegen->BuildVMapTable(&vmap_table);
167  std::vector<uint8_t> gc_map;
168  codegen->BuildNativeGCMap(&gc_map, dex_compilation_unit);
169
170  return new CompiledMethod(GetCompilerDriver(),
171                            instruction_set,
172                            allocator.GetMemory(),
173                            codegen->GetFrameSize(),
174                            codegen->GetCoreSpillMask(),
175                            0, /* FPR spill mask, unused */
176                            mapping_table,
177                            vmap_table,
178                            gc_map,
179                            nullptr);
180}
181
182}  // namespace art
183