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 #ifndef ART_COMPILER_OPTIMIZING_SIDE_EFFECTS_ANALYSIS_H_
18 #define ART_COMPILER_OPTIMIZING_SIDE_EFFECTS_ANALYSIS_H_
19 
20 #include "nodes.h"
21 #include "optimization.h"
22 
23 namespace art {
24 
25 class SideEffectsAnalysis : public HOptimization {
26  public:
SideEffectsAnalysis(HGraph * graph)27   explicit SideEffectsAnalysis(HGraph* graph)
28       : HOptimization(graph, true, kSideEffectsAnalysisPassName),
29         graph_(graph),
30         block_effects_(graph->GetArena(), graph->GetBlocks().Size(), SideEffects::None()),
31         loop_effects_(graph->GetArena(), graph->GetBlocks().Size(), SideEffects::None()) {}
32 
33   SideEffects GetLoopEffects(HBasicBlock* block) const;
34   SideEffects GetBlockEffects(HBasicBlock* block) const;
35 
36   // Compute side effects of individual blocks and loops.
37   void Run();
38 
HasRun()39   bool HasRun() const { return has_run_; }
40 
41   static constexpr const char* kSideEffectsAnalysisPassName = "SideEffects";
42 
43  private:
44   void UpdateLoopEffects(HLoopInformation* info, SideEffects effects);
45 
46   HGraph* graph_;
47 
48   // Checked in debug build, to ensure the pass has been run prior to
49   // running a pass that depends on it.
50   bool has_run_ = false;
51 
52   // Side effects of individual blocks, that is the union of the side effects
53   // of the instructions in the block.
54   GrowableArray<SideEffects> block_effects_;
55 
56   // Side effects of loops, that is the union of the side effects of the
57   // blocks contained in that loop.
58   GrowableArray<SideEffects> loop_effects_;
59 
60   ART_FRIEND_TEST(GVNTest, LoopSideEffects);
61   DISALLOW_COPY_AND_ASSIGN(SideEffectsAnalysis);
62 };
63 
64 }  // namespace art
65 
66 #endif  // ART_COMPILER_OPTIMIZING_SIDE_EFFECTS_ANALYSIS_H_
67