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