1// Copyright (c) 2017 The Khronos Group Inc.
2// Copyright (c) 2017 Valve Corporation
3// Copyright (c) 2017 LunarG Inc.
4//
5// Licensed under the Apache License, Version 2.0 (the "License");
6// you may not use this file except in compliance with the License.
7// You may obtain a copy of the License at
8//
9// http://www.apache.org/licenses/LICENSE-2.0
10//
11// Unless required by applicable law or agreed to in writing, software
12// distributed under the License is distributed on an "AS IS" BASIS,
13// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14// See the License for the specific language governing permissions and
15// limitations under the License.
16
17#ifndef SOURCE_OPT_BLOCK_MERGE_PASS_H_
18#define SOURCE_OPT_BLOCK_MERGE_PASS_H_
19
20#include <algorithm>
21#include <map>
22#include <queue>
23#include <unordered_map>
24#include <unordered_set>
25#include <utility>
26
27#include "source/opt/basic_block.h"
28#include "source/opt/def_use_manager.h"
29#include "source/opt/ir_context.h"
30#include "source/opt/module.h"
31#include "source/opt/pass.h"
32
33namespace spvtools {
34namespace opt {
35
36// See optimizer.hpp for documentation.
37class BlockMergePass : public Pass {
38 public:
39 BlockMergePass();
40 const char* name() const override { return "merge-blocks"; }
41 Status Process() override;
42
43 IRContext::Analysis GetPreservedAnalyses() override {
44 return IRContext::kAnalysisDefUse |
45 IRContext::kAnalysisInstrToBlockMapping |
46 IRContext::kAnalysisDecorations | IRContext::kAnalysisCombinators |
47 IRContext::kAnalysisNameMap | IRContext::kAnalysisConstants |
48 IRContext::kAnalysisTypes;
49 }
50
51 private:
52
53 // Search |func| for blocks which have a single Branch to a block
54 // with no other predecessors. Merge these blocks into a single block.
55 bool MergeBlocks(Function* func);
56
57};
58
59} // namespace opt
60} // namespace spvtools
61
62#endif // SOURCE_OPT_BLOCK_MERGE_PASS_H_
63