| // 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_copy_objects.h" |
| |
| #include "source/fuzz/fuzzer_util.h" |
| #include "source/fuzz/protobufs/spirvfuzz_protobufs.h" |
| #include "source/fuzz/transformation_add_synonym.h" |
| |
| namespace spvtools { |
| namespace fuzz { |
| |
| FuzzerPassCopyObjects::FuzzerPassCopyObjects( |
| opt::IRContext* ir_context, TransformationContext* transformation_context, |
| FuzzerContext* fuzzer_context, |
| protobufs::TransformationSequence* transformations, |
| bool ignore_inapplicable_transformations) |
| : FuzzerPass(ir_context, transformation_context, fuzzer_context, |
| transformations, ignore_inapplicable_transformations) {} |
| |
| void FuzzerPassCopyObjects::Apply() { |
| ForEachInstructionWithInstructionDescriptor( |
| [this](opt::Function* function, opt::BasicBlock* block, |
| opt::BasicBlock::iterator inst_it, |
| const protobufs::InstructionDescriptor& instruction_descriptor) |
| -> void { |
| assert( |
| inst_it->opcode() == |
| spv::Op(instruction_descriptor.target_instruction_opcode()) && |
| "The opcode of the instruction we might insert before must be " |
| "the same as the opcode in the descriptor for the instruction"); |
| |
| if (GetTransformationContext()->GetFactManager()->BlockIsDead( |
| block->id())) { |
| // Don't create synonyms in dead blocks. |
| return; |
| } |
| |
| // Check whether it is legitimate to insert a copy before this |
| // instruction. |
| if (!fuzzerutil::CanInsertOpcodeBeforeInstruction(spv::Op::OpCopyObject, |
| inst_it)) { |
| return; |
| } |
| |
| // Randomly decide whether to try inserting an object copy here. |
| if (!GetFuzzerContext()->ChoosePercentage( |
| GetFuzzerContext()->GetChanceOfCopyingObject())) { |
| return; |
| } |
| |
| const auto relevant_instructions = FindAvailableInstructions( |
| function, block, inst_it, |
| [this](opt::IRContext* ir_context, opt::Instruction* inst) { |
| return TransformationAddSynonym::IsInstructionValid( |
| ir_context, *GetTransformationContext(), inst, |
| protobufs::TransformationAddSynonym::COPY_OBJECT); |
| }); |
| |
| // At this point, |relevant_instructions| contains all the instructions |
| // we might think of copying. |
| if (relevant_instructions.empty()) { |
| return; |
| } |
| |
| // Choose a copyable instruction at random, and create and apply an |
| // object copying transformation based on it. |
| ApplyTransformation(TransformationAddSynonym( |
| relevant_instructions[GetFuzzerContext()->RandomIndex( |
| relevant_instructions)] |
| ->result_id(), |
| protobufs::TransformationAddSynonym::COPY_OBJECT, |
| GetFuzzerContext()->GetFreshId(), instruction_descriptor)); |
| }); |
| } |
| |
| } // namespace fuzz |
| } // namespace spvtools |