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 "builder.h"
18
19 #include "art_field-inl.h"
20 #include "base/arena_bit_vector.h"
21 #include "base/bit_vector-inl.h"
22 #include "base/logging.h"
23 #include "block_builder.h"
24 #include "code_generator.h"
25 #include "data_type-inl.h"
26 #include "dex/verified_method.h"
27 #include "driver/compiler_options.h"
28 #include "driver/dex_compilation_unit.h"
29 #include "instruction_builder.h"
30 #include "mirror/class_loader.h"
31 #include "mirror/dex_cache.h"
32 #include "nodes.h"
33 #include "optimizing_compiler_stats.h"
34 #include "ssa_builder.h"
35 #include "thread.h"
36 #include "utils/dex_cache_arrays_layout-inl.h"
37
38 namespace art {
39
HGraphBuilder(HGraph * graph,const CodeItemDebugInfoAccessor & accessor,const DexCompilationUnit * dex_compilation_unit,const DexCompilationUnit * outer_compilation_unit,CodeGenerator * code_generator,OptimizingCompilerStats * compiler_stats,ArrayRef<const uint8_t> interpreter_metadata,VariableSizedHandleScope * handles)40 HGraphBuilder::HGraphBuilder(HGraph* graph,
41 const CodeItemDebugInfoAccessor& accessor,
42 const DexCompilationUnit* dex_compilation_unit,
43 const DexCompilationUnit* outer_compilation_unit,
44 CodeGenerator* code_generator,
45 OptimizingCompilerStats* compiler_stats,
46 ArrayRef<const uint8_t> interpreter_metadata,
47 VariableSizedHandleScope* handles)
48 : graph_(graph),
49 dex_file_(&graph->GetDexFile()),
50 code_item_accessor_(accessor),
51 dex_compilation_unit_(dex_compilation_unit),
52 outer_compilation_unit_(outer_compilation_unit),
53 code_generator_(code_generator),
54 compilation_stats_(compiler_stats),
55 interpreter_metadata_(interpreter_metadata),
56 handles_(handles),
57 return_type_(DataType::FromShorty(dex_compilation_unit_->GetShorty()[0])) {}
58
HGraphBuilder(HGraph * graph,const DexCompilationUnit * dex_compilation_unit,const CodeItemDebugInfoAccessor & accessor,VariableSizedHandleScope * handles,DataType::Type return_type)59 HGraphBuilder::HGraphBuilder(HGraph* graph,
60 const DexCompilationUnit* dex_compilation_unit,
61 const CodeItemDebugInfoAccessor& accessor,
62 VariableSizedHandleScope* handles,
63 DataType::Type return_type)
64 : graph_(graph),
65 dex_file_(&graph->GetDexFile()),
66 code_item_accessor_(accessor),
67 dex_compilation_unit_(dex_compilation_unit),
68 outer_compilation_unit_(nullptr),
69 code_generator_(nullptr),
70 compilation_stats_(nullptr),
71 handles_(handles),
72 return_type_(return_type) {}
73
SkipCompilation(size_t number_of_branches)74 bool HGraphBuilder::SkipCompilation(size_t number_of_branches) {
75 if (code_generator_ == nullptr) {
76 // Note that the codegen is null when unit testing.
77 return false;
78 }
79
80 const CompilerOptions& compiler_options = code_generator_->GetCompilerOptions();
81 CompilerFilter::Filter compiler_filter = compiler_options.GetCompilerFilter();
82 if (compiler_filter == CompilerFilter::kEverything) {
83 return false;
84 }
85
86 const uint32_t code_units = code_item_accessor_.InsnsSizeInCodeUnits();
87 if (compiler_options.IsHugeMethod(code_units)) {
88 VLOG(compiler) << "Skip compilation of huge method "
89 << dex_file_->PrettyMethod(dex_compilation_unit_->GetDexMethodIndex())
90 << ": " << code_units << " code units";
91 MaybeRecordStat(compilation_stats_, MethodCompilationStat::kNotCompiledHugeMethod);
92 return true;
93 }
94
95 // If it's large and contains no branches, it's likely to be machine generated initialization.
96 if (compiler_options.IsLargeMethod(code_units) && (number_of_branches == 0)) {
97 VLOG(compiler) << "Skip compilation of large method with no branch "
98 << dex_file_->PrettyMethod(dex_compilation_unit_->GetDexMethodIndex())
99 << ": " << code_units << " code units";
100 MaybeRecordStat(compilation_stats_, MethodCompilationStat::kNotCompiledLargeMethodNoBranches);
101 return true;
102 }
103
104 return false;
105 }
106
BuildGraph()107 GraphAnalysisResult HGraphBuilder::BuildGraph() {
108 DCHECK(code_item_accessor_.HasCodeItem());
109 DCHECK(graph_->GetBlocks().empty());
110
111 graph_->SetNumberOfVRegs(code_item_accessor_.RegistersSize());
112 graph_->SetNumberOfInVRegs(code_item_accessor_.InsSize());
113 graph_->SetMaximumNumberOfOutVRegs(code_item_accessor_.OutsSize());
114 graph_->SetHasTryCatch(code_item_accessor_.TriesSize() != 0);
115
116 // Use ScopedArenaAllocator for all local allocations.
117 ScopedArenaAllocator local_allocator(graph_->GetArenaStack());
118 HBasicBlockBuilder block_builder(graph_, dex_file_, code_item_accessor_, &local_allocator);
119 SsaBuilder ssa_builder(graph_,
120 dex_compilation_unit_->GetClassLoader(),
121 dex_compilation_unit_->GetDexCache(),
122 handles_,
123 &local_allocator);
124 HInstructionBuilder instruction_builder(graph_,
125 &block_builder,
126 &ssa_builder,
127 dex_file_,
128 code_item_accessor_,
129 return_type_,
130 dex_compilation_unit_,
131 outer_compilation_unit_,
132 code_generator_,
133 interpreter_metadata_,
134 compilation_stats_,
135 handles_,
136 &local_allocator);
137
138 // 1) Create basic blocks and link them together. Basic blocks are left
139 // unpopulated with the exception of synthetic blocks, e.g. HTryBoundaries.
140 if (!block_builder.Build()) {
141 return kAnalysisInvalidBytecode;
142 }
143
144 // 2) Decide whether to skip this method based on its code size and number
145 // of branches.
146 if (SkipCompilation(block_builder.GetNumberOfBranches())) {
147 return kAnalysisSkipped;
148 }
149
150 // 3) Build the dominator tree and fill in loop and try/catch metadata.
151 GraphAnalysisResult result = graph_->BuildDominatorTree();
152 if (result != kAnalysisSuccess) {
153 return result;
154 }
155
156 // 4) Populate basic blocks with instructions.
157 if (!instruction_builder.Build()) {
158 return kAnalysisInvalidBytecode;
159 }
160
161 // 5) Type the graph and eliminate dead/redundant phis.
162 return ssa_builder.BuildSsa();
163 }
164
BuildIntrinsicGraph(ArtMethod * method)165 void HGraphBuilder::BuildIntrinsicGraph(ArtMethod* method) {
166 DCHECK(!code_item_accessor_.HasCodeItem());
167 DCHECK(graph_->GetBlocks().empty());
168
169 // Determine the number of arguments and associated vregs.
170 uint32_t method_idx = dex_compilation_unit_->GetDexMethodIndex();
171 const char* shorty = dex_file_->GetMethodShorty(dex_file_->GetMethodId(method_idx));
172 size_t num_args = strlen(shorty + 1);
173 size_t num_wide_args = std::count(shorty + 1, shorty + 1 + num_args, 'J') +
174 std::count(shorty + 1, shorty + 1 + num_args, 'D');
175 size_t num_arg_vregs = num_args + num_wide_args + (dex_compilation_unit_->IsStatic() ? 0u : 1u);
176
177 // For simplicity, reserve 2 vregs (the maximum) for return value regardless of the return type.
178 size_t return_vregs = 2u;
179 graph_->SetNumberOfVRegs(return_vregs + num_arg_vregs);
180 graph_->SetNumberOfInVRegs(num_arg_vregs);
181 graph_->SetMaximumNumberOfOutVRegs(num_arg_vregs);
182 graph_->SetHasTryCatch(false);
183
184 // Use ScopedArenaAllocator for all local allocations.
185 ScopedArenaAllocator local_allocator(graph_->GetArenaStack());
186 HBasicBlockBuilder block_builder(graph_,
187 dex_file_,
188 CodeItemDebugInfoAccessor(),
189 &local_allocator);
190 SsaBuilder ssa_builder(graph_,
191 dex_compilation_unit_->GetClassLoader(),
192 dex_compilation_unit_->GetDexCache(),
193 handles_,
194 &local_allocator);
195 HInstructionBuilder instruction_builder(graph_,
196 &block_builder,
197 &ssa_builder,
198 dex_file_,
199 CodeItemDebugInfoAccessor(),
200 return_type_,
201 dex_compilation_unit_,
202 outer_compilation_unit_,
203 code_generator_,
204 interpreter_metadata_,
205 compilation_stats_,
206 handles_,
207 &local_allocator);
208
209 // 1) Create basic blocks for the intrinsic and link them together.
210 block_builder.BuildIntrinsic();
211
212 // 2) Build the trivial dominator tree.
213 GraphAnalysisResult bdt_result = graph_->BuildDominatorTree();
214 DCHECK_EQ(bdt_result, kAnalysisSuccess);
215
216 // 3) Populate basic blocks with instructions for the intrinsic.
217 instruction_builder.BuildIntrinsic(method);
218
219 // 4) Type the graph (no dead/redundant phis to eliminate).
220 GraphAnalysisResult build_ssa_result = ssa_builder.BuildSsa();
221 DCHECK_EQ(build_ssa_result, kAnalysisSuccess);
222 }
223
224 } // namespace art
225