| // 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. |
| |
| #include "source/fuzz/fuzzer_pass_add_dead_blocks.h" |
| |
| #include "source/fuzz/fuzzer_util.h" |
| #include "source/fuzz/transformation_add_dead_block.h" |
| |
| namespace spvtools { |
| namespace fuzz { |
| |
| FuzzerPassAddDeadBlocks::FuzzerPassAddDeadBlocks( |
| opt::IRContext* ir_context, FactManager* fact_manager, |
| FuzzerContext* fuzzer_context, |
| protobufs::TransformationSequence* transformations) |
| : FuzzerPass(ir_context, fact_manager, fuzzer_context, transformations) {} |
| |
| FuzzerPassAddDeadBlocks::~FuzzerPassAddDeadBlocks() = default; |
| |
| void FuzzerPassAddDeadBlocks::Apply() { |
| // We iterate over all blocks in the module collecting up those at which we |
| // might add a branch to a new dead block. We then loop over all such |
| // candidates and actually apply transformations. This separation is to |
| // avoid modifying the module as we traverse it. |
| std::vector<TransformationAddDeadBlock> candidate_transformations; |
| for (auto& function : *GetIRContext()->module()) { |
| for (auto& block : function) { |
| if (!GetFuzzerContext()->ChoosePercentage( |
| GetFuzzerContext()->GetChanceOfAddingDeadBlock())) { |
| continue; |
| } |
| // We speculatively create a transformation, and then apply it (below) if |
| // it turns out to be applicable. This avoids duplicating the logic for |
| // applicability checking. |
| // |
| // It means that fresh ids for transformations that turn out not to be |
| // applicable end up being unused. |
| candidate_transformations.emplace_back(TransformationAddDeadBlock( |
| GetFuzzerContext()->GetFreshId(), block.id(), |
| GetFuzzerContext()->ChooseEven())); |
| } |
| } |
| // Apply all those transformations that are in fact applicable. |
| for (auto& transformation : candidate_transformations) { |
| if (transformation.IsApplicable(GetIRContext(), *GetFactManager())) { |
| transformation.Apply(GetIRContext(), GetFactManager()); |
| *GetTransformations()->add_transformation() = transformation.ToMessage(); |
| } |
| } |
| } |
| |
| } // namespace fuzz |
| } // namespace spvtools |