SPIRV-Tools/source/fuzz/transformation_merge_blocks.h
Alastair Donaldson b8587c984a
spirv-reduce: Allow merging unreachable blocks (#4303)
This change allows the reducer to merge together blocks even when they
are unreachable, but keeps the restriction of reachability in place
for the optimizer.

Fixes #4302.
2021-06-28 23:05:30 +01:00

60 lines
2.1 KiB
C++

// Copyright (c) 2019 Google LLC
//
// 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 SOURCE_FUZZ_TRANSFORMATION_MERGE_BLOCKS_H_
#define SOURCE_FUZZ_TRANSFORMATION_MERGE_BLOCKS_H_
#include "source/fuzz/protobufs/spirvfuzz_protobufs.h"
#include "source/fuzz/transformation.h"
#include "source/fuzz/transformation_context.h"
#include "source/opt/ir_context.h"
namespace spvtools {
namespace fuzz {
class TransformationMergeBlocks : public Transformation {
public:
explicit TransformationMergeBlocks(
protobufs::TransformationMergeBlocks message);
TransformationMergeBlocks(uint32_t block_id);
// - |message_.block_id| must be the id of a block, b
// - b must be statically reachable in the control flow graph of its function
// - b must have a single predecessor, a
// - b must be the sole successor of a
// - Replacing a with the merge of a and b (and removing b) must lead to a
// valid module
bool IsApplicable(
opt::IRContext* ir_context,
const TransformationContext& transformation_context) const override;
// The contents of b are merged into a, and a's terminator is replaced with
// the terminator of b. Block b is removed from the module.
void Apply(opt::IRContext* ir_context,
TransformationContext* transformation_context) const override;
std::unordered_set<uint32_t> GetFreshIds() const override;
protobufs::Transformation ToMessage() const override;
private:
protobufs::TransformationMergeBlocks message_;
};
} // namespace fuzz
} // namespace spvtools
#endif // SOURCE_FUZZ_TRANSFORMATION_MERGE_BLOCKS_H_