SPIRV-Tools/source/fuzz/transformation_add_dead_block.h
Alastair Donaldson fcb22ecf0f
spirv-fuzz: Report fresh ids in transformations (#3856)
Adds a virtual method, GetFreshIds(), to Transformation. Every
transformation uses this to indicate which ids in its protobuf message
are fresh ids. This means that when replaying a sequence of
transformations the replayer can obtain a smallest id that is not in
use by the module already and that will not be used by any
transformation by necessity. Ids greater than or equal to this id
can be used as overflow ids.

Fixes #3851.
2020-09-29 22:12:49 +01:00

68 lines
2.7 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_ADD_DEAD_BLOCK_H_
#define SOURCE_FUZZ_TRANSFORMATION_ADD_DEAD_BLOCK_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 TransformationAddDeadBlock : public Transformation {
public:
explicit TransformationAddDeadBlock(
const protobufs::TransformationAddDeadBlock& message);
TransformationAddDeadBlock(uint32_t fresh_id, uint32_t existing_block,
bool condition_value);
// - |message_.fresh_id| must be a fresh id
// - A constant with the same value as |message_.condition_value| must be
// available
// - |message_.existing_block| must be a block that is not a loop header,
// and that ends with OpBranch to a block that is not a merge block nor
// continue target - this is because the successor will become the merge
// block of a selection construct headed at |message_.existing_block|
// - |message_.existing_block| must not be a back-edge block, since in this
// case the newly-added block would lead to another back-edge to the
// associated loop header
bool IsApplicable(
opt::IRContext* ir_context,
const TransformationContext& transformation_context) const override;
// Changes the OpBranch from |message_.existing_block| to its successor 's'
// to an OpBranchConditional to either 's' or a new block,
// |message_.fresh_id|, which itself unconditionally branches to 's'. The
// conditional branch uses |message.condition_value| as its condition, and is
// arranged so that control will pass to 's' at runtime.
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::TransformationAddDeadBlock message_;
};
} // namespace fuzz
} // namespace spvtools
#endif // SOURCE_FUZZ_TRANSFORMATION_ADD_DEAD_BLOCK_H_