graph_checker_test.cc revision badd826664896d4a9628a5a89b78016894aa414b 
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 "graph_checker.h"
18#include "optimizing_unit_test.h"
19
20namespace art {
21
22/**
23 * Create a simple control-flow graph composed of two blocks:
24 *
25 *   BasicBlock 0, succ: 1
26 *     0: ReturnVoid 1
27 *   BasicBlock 1, pred: 0
28 *     1: Exit
29 */
30HGraph* CreateSimpleCFG(ArenaAllocator* allocator) {
31  HGraph* graph = CreateGraph(allocator);
32  HBasicBlock* entry_block = new (allocator) HBasicBlock(graph);
33  entry_block->AddInstruction(new (allocator) HReturnVoid());
34  graph->AddBlock(entry_block);
35  graph->SetEntryBlock(entry_block);
36  HBasicBlock* exit_block = new (allocator) HBasicBlock(graph);
37  exit_block->AddInstruction(new (allocator) HExit());
38  graph->AddBlock(exit_block);
39  graph->SetExitBlock(exit_block);
40  entry_block->AddSuccessor(exit_block);
41  return graph;
42}
43
44static void TestCode(const uint16_t* data) {
45  ArenaPool pool;
46  ArenaAllocator allocator(&pool);
47  HGraph* graph = CreateCFG(&allocator, data);
48  ASSERT_NE(graph, nullptr);
49
50  GraphChecker graph_checker(graph);
51  graph_checker.Run();
52  ASSERT_TRUE(graph_checker.IsValid());
53}
54
55class GraphCheckerTest : public CommonCompilerTest {};
56
57TEST_F(GraphCheckerTest, ReturnVoid) {
58  const uint16_t data[] = ZERO_REGISTER_CODE_ITEM(
59      Instruction::RETURN_VOID);
60
61  TestCode(data);
62}
63
64TEST_F(GraphCheckerTest, CFG1) {
65  const uint16_t data[] = ZERO_REGISTER_CODE_ITEM(
66      Instruction::GOTO | 0x100,
67      Instruction::RETURN_VOID);
68
69  TestCode(data);
70}
71
72TEST_F(GraphCheckerTest, CFG2) {
73  const uint16_t data[] = ONE_REGISTER_CODE_ITEM(
74    Instruction::CONST_4 | 0 | 0,
75    Instruction::IF_EQ, 3,
76    Instruction::GOTO | 0x100,
77    Instruction::RETURN_VOID);
78
79  TestCode(data);
80}
81
82TEST_F(GraphCheckerTest, CFG3) {
83  const uint16_t data[] = ONE_REGISTER_CODE_ITEM(
84    Instruction::CONST_4 | 0 | 0,
85    Instruction::IF_EQ, 3,
86    Instruction::GOTO | 0x100,
87    Instruction::GOTO | 0xFF00);
88
89  TestCode(data);
90}
91
92// Test case with an invalid graph containing inconsistent
93// predecessor/successor arcs in CFG.
94TEST_F(GraphCheckerTest, InconsistentPredecessorsAndSuccessors) {
95  ArenaPool pool;
96  ArenaAllocator allocator(&pool);
97
98  HGraph* graph = CreateSimpleCFG(&allocator);
99  GraphChecker graph_checker(graph);
100  graph_checker.Run();
101  ASSERT_TRUE(graph_checker.IsValid());
102
103  // Remove the entry block from the exit block's predecessors, to create an
104  // inconsistent successor/predecessor relation.
105  graph->GetExitBlock()->RemovePredecessor(graph->GetEntryBlock());
106  graph_checker.Run();
107  ASSERT_FALSE(graph_checker.IsValid());
108}
109
110// Test case with an invalid graph containing a non-branch last
111// instruction in a block.
112TEST_F(GraphCheckerTest, BlockEndingWithNonBranchInstruction) {
113  ArenaPool pool;
114  ArenaAllocator allocator(&pool);
115
116  HGraph* graph = CreateSimpleCFG(&allocator);
117  GraphChecker graph_checker(graph);
118  graph_checker.Run();
119  ASSERT_TRUE(graph_checker.IsValid());
120
121  // Remove the sole instruction of the exit block (composed of a
122  // single Exit instruction) to make it invalid (i.e. not ending by a
123  // branch instruction).
124  HBasicBlock* exit_block = graph->GetExitBlock();
125  HInstruction* last_inst = exit_block->GetLastInstruction();
126  exit_block->RemoveInstruction(last_inst);
127
128  graph_checker.Run();
129  ASSERT_FALSE(graph_checker.IsValid());
130}
131
132TEST_F(GraphCheckerTest, SSAPhi) {
133  // This code creates one Phi function during the conversion to SSA form.
134  const uint16_t data[] = ONE_REGISTER_CODE_ITEM(
135    Instruction::CONST_4 | 0 | 0,
136    Instruction::IF_EQ, 3,
137    Instruction::CONST_4 | 4 << 12 | 0,
138    Instruction::RETURN | 0 << 8);
139
140  TestCode(data);
141}
142
143}  // namespace art
144