1 /*
2 * Copyright (C) 2015 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 "base/arena_allocator.h"
18 #include "builder.h"
19 #include "licm.h"
20 #include "nodes.h"
21 #include "optimizing_unit_test.h"
22 #include "side_effects_analysis.h"
23
24 namespace art {
25
26 /**
27 * Fixture class for the LICM tests.
28 */
29 class LICMTest : public CommonCompilerTest {
30 public:
LICMTest()31 LICMTest() : pool_(), allocator_(&pool_) {
32 graph_ = CreateGraph(&allocator_);
33 }
34
~LICMTest()35 ~LICMTest() { }
36
37 // Builds a singly-nested loop structure in CFG. Tests can further populate
38 // the basic blocks with instructions to set up interesting scenarios.
BuildLoop()39 void BuildLoop() {
40 entry_ = new (&allocator_) HBasicBlock(graph_);
41 loop_preheader_ = new (&allocator_) HBasicBlock(graph_);
42 loop_header_ = new (&allocator_) HBasicBlock(graph_);
43 loop_body_ = new (&allocator_) HBasicBlock(graph_);
44 return_ = new (&allocator_) HBasicBlock(graph_);
45 exit_ = new (&allocator_) HBasicBlock(graph_);
46
47 graph_->AddBlock(entry_);
48 graph_->AddBlock(loop_preheader_);
49 graph_->AddBlock(loop_header_);
50 graph_->AddBlock(loop_body_);
51 graph_->AddBlock(return_);
52 graph_->AddBlock(exit_);
53
54 graph_->SetEntryBlock(entry_);
55 graph_->SetExitBlock(exit_);
56
57 // Set up loop flow in CFG.
58 entry_->AddSuccessor(loop_preheader_);
59 loop_preheader_->AddSuccessor(loop_header_);
60 loop_header_->AddSuccessor(loop_body_);
61 loop_header_->AddSuccessor(return_);
62 loop_body_->AddSuccessor(loop_header_);
63 return_->AddSuccessor(exit_);
64
65 // Provide boiler-plate instructions.
66 parameter_ = new (&allocator_) HParameterValue(graph_->GetDexFile(), 0, 0, Primitive::kPrimNot);
67 entry_->AddInstruction(parameter_);
68 int_constant_ = graph_->GetIntConstant(42);
69 float_constant_ = graph_->GetFloatConstant(42.0f);
70 loop_preheader_->AddInstruction(new (&allocator_) HGoto());
71 loop_header_->AddInstruction(new (&allocator_) HIf(parameter_));
72 loop_body_->AddInstruction(new (&allocator_) HGoto());
73 return_->AddInstruction(new (&allocator_) HReturnVoid());
74 exit_->AddInstruction(new (&allocator_) HExit());
75 }
76
77 // Performs LICM optimizations (after proper set up).
PerformLICM()78 void PerformLICM() {
79 graph_->BuildDominatorTree();
80 SideEffectsAnalysis side_effects(graph_);
81 side_effects.Run();
82 LICM(graph_, side_effects, nullptr).Run();
83 }
84
85 // General building fields.
86 ArenaPool pool_;
87 ArenaAllocator allocator_;
88 HGraph* graph_;
89
90 // Specific basic blocks.
91 HBasicBlock* entry_;
92 HBasicBlock* loop_preheader_;
93 HBasicBlock* loop_header_;
94 HBasicBlock* loop_body_;
95 HBasicBlock* return_;
96 HBasicBlock* exit_;
97
98 HInstruction* parameter_; // "this"
99 HInstruction* int_constant_;
100 HInstruction* float_constant_;
101 };
102
103 //
104 // The actual LICM tests.
105 //
106
TEST_F(LICMTest,FieldHoisting)107 TEST_F(LICMTest, FieldHoisting) {
108 BuildLoop();
109
110 // Populate the loop with instructions: set/get field with different types.
111 ScopedNullHandle<mirror::DexCache> dex_cache;
112 HInstruction* get_field = new (&allocator_) HInstanceFieldGet(parameter_,
113 Primitive::kPrimLong,
114 MemberOffset(10),
115 false,
116 kUnknownFieldIndex,
117 kUnknownClassDefIndex,
118 graph_->GetDexFile(),
119 dex_cache,
120 0);
121 loop_body_->InsertInstructionBefore(get_field, loop_body_->GetLastInstruction());
122 HInstruction* set_field = new (&allocator_) HInstanceFieldSet(
123 parameter_, int_constant_, Primitive::kPrimInt, MemberOffset(20),
124 false, kUnknownFieldIndex, kUnknownClassDefIndex, graph_->GetDexFile(), dex_cache, 0);
125 loop_body_->InsertInstructionBefore(set_field, loop_body_->GetLastInstruction());
126
127 EXPECT_EQ(get_field->GetBlock(), loop_body_);
128 EXPECT_EQ(set_field->GetBlock(), loop_body_);
129 PerformLICM();
130 EXPECT_EQ(get_field->GetBlock(), loop_preheader_);
131 EXPECT_EQ(set_field->GetBlock(), loop_body_);
132 }
133
TEST_F(LICMTest,NoFieldHoisting)134 TEST_F(LICMTest, NoFieldHoisting) {
135 BuildLoop();
136
137 // Populate the loop with instructions: set/get field with same types.
138 ScopedNullHandle<mirror::DexCache> dex_cache;
139 HInstruction* get_field = new (&allocator_) HInstanceFieldGet(parameter_,
140 Primitive::kPrimLong,
141 MemberOffset(10),
142 false,
143 kUnknownFieldIndex,
144 kUnknownClassDefIndex,
145 graph_->GetDexFile(),
146 dex_cache,
147 0);
148 loop_body_->InsertInstructionBefore(get_field, loop_body_->GetLastInstruction());
149 HInstruction* set_field = new (&allocator_) HInstanceFieldSet(parameter_,
150 get_field,
151 Primitive::kPrimLong,
152 MemberOffset(10),
153 false,
154 kUnknownFieldIndex,
155 kUnknownClassDefIndex,
156 graph_->GetDexFile(),
157 dex_cache,
158 0);
159 loop_body_->InsertInstructionBefore(set_field, loop_body_->GetLastInstruction());
160
161 EXPECT_EQ(get_field->GetBlock(), loop_body_);
162 EXPECT_EQ(set_field->GetBlock(), loop_body_);
163 PerformLICM();
164 EXPECT_EQ(get_field->GetBlock(), loop_body_);
165 EXPECT_EQ(set_field->GetBlock(), loop_body_);
166 }
167
TEST_F(LICMTest,ArrayHoisting)168 TEST_F(LICMTest, ArrayHoisting) {
169 BuildLoop();
170
171 // Populate the loop with instructions: set/get array with different types.
172 // ArrayGet is typed as kPrimByte and ArraySet given a float value in order to
173 // avoid SsaBuilder's typing of ambiguous array operations from reference type info.
174 HInstruction* get_array = new (&allocator_) HArrayGet(
175 parameter_, int_constant_, Primitive::kPrimByte, 0);
176 loop_body_->InsertInstructionBefore(get_array, loop_body_->GetLastInstruction());
177 HInstruction* set_array = new (&allocator_) HArraySet(
178 parameter_, int_constant_, float_constant_, Primitive::kPrimShort, 0);
179 loop_body_->InsertInstructionBefore(set_array, loop_body_->GetLastInstruction());
180
181 EXPECT_EQ(get_array->GetBlock(), loop_body_);
182 EXPECT_EQ(set_array->GetBlock(), loop_body_);
183 PerformLICM();
184 EXPECT_EQ(get_array->GetBlock(), loop_preheader_);
185 EXPECT_EQ(set_array->GetBlock(), loop_body_);
186 }
187
TEST_F(LICMTest,NoArrayHoisting)188 TEST_F(LICMTest, NoArrayHoisting) {
189 BuildLoop();
190
191 // Populate the loop with instructions: set/get array with same types.
192 // ArrayGet is typed as kPrimByte and ArraySet given a float value in order to
193 // avoid SsaBuilder's typing of ambiguous array operations from reference type info.
194 HInstruction* get_array = new (&allocator_) HArrayGet(
195 parameter_, int_constant_, Primitive::kPrimByte, 0);
196 loop_body_->InsertInstructionBefore(get_array, loop_body_->GetLastInstruction());
197 HInstruction* set_array = new (&allocator_) HArraySet(
198 parameter_, get_array, float_constant_, Primitive::kPrimByte, 0);
199 loop_body_->InsertInstructionBefore(set_array, loop_body_->GetLastInstruction());
200
201 EXPECT_EQ(get_array->GetBlock(), loop_body_);
202 EXPECT_EQ(set_array->GetBlock(), loop_body_);
203 PerformLICM();
204 EXPECT_EQ(get_array->GetBlock(), loop_body_);
205 EXPECT_EQ(set_array->GetBlock(), loop_body_);
206 }
207
208 } // namespace art
209