SPIRV-Tools/source/opt/block_merge_pass.h
David Neto 340370eddb Remove extension whitelist from some transforms
Remove extension whitelists from transforms that are essentially
combinatorial (and avoiding pointers) or which affect only control flow.
It's very very unlikely an extension will add a new control flow construct.

Remove from:
- dead branch elimination
- dead insertion elimination
- insert extract elimination
- block merge

Fixes https://github.com/KhronosGroup/SPIRV-Tools/issues/1392
2018-03-08 12:25:49 -05:00

68 lines
2.0 KiB
C++

// Copyright (c) 2017 The Khronos Group Inc.
// Copyright (c) 2017 Valve Corporation
// Copyright (c) 2017 LunarG Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef LIBSPIRV_OPT_BLOCK_MERGE_PASS_H_
#define LIBSPIRV_OPT_BLOCK_MERGE_PASS_H_
#include <algorithm>
#include <map>
#include <queue>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include "basic_block.h"
#include "def_use_manager.h"
#include "ir_context.h"
#include "module.h"
#include "pass.h"
namespace spvtools {
namespace opt {
// See optimizer.hpp for documentation.
class BlockMergePass : public Pass {
public:
BlockMergePass();
const char* name() const override { return "merge-blocks"; }
Status Process(ir::IRContext*) override;
private:
// Kill any OpName instruction referencing |inst|, then kill |inst|.
void KillInstAndName(ir::Instruction* inst);
// Search |func| for blocks which have a single Branch to a block
// with no other predecessors. Merge these blocks into a single block.
bool MergeBlocks(ir::Function* func);
// Returns true if |block| (or |id|) contains a merge instruction.
bool IsHeader(ir::BasicBlock* block);
bool IsHeader(uint32_t id);
// Returns true if |block| (or |id|) is the merge target of a merge
// instruction.
bool IsMerge(ir::BasicBlock* block);
bool IsMerge(uint32_t id);
void Initialize(ir::IRContext* c);
Pass::Status ProcessImpl();
};
} // namespace opt
} // namespace spvtools
#endif // LIBSPIRV_OPT_BLOCK_MERGE_PASS_H_