1 // Copyright 2021 The Tint Authors. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #ifndef FUZZERS_TINT_AST_FUZZER_MUTATION_H_ 16 #define FUZZERS_TINT_AST_FUZZER_MUTATION_H_ 17 18 #include <memory> 19 #include <vector> 20 21 #include "fuzzers/tint_ast_fuzzer/node_id_map.h" 22 #include "fuzzers/tint_ast_fuzzer/protobufs/tint_ast_fuzzer.h" 23 24 #include "src/clone_context.h" 25 #include "src/program.h" 26 27 namespace tint { 28 namespace fuzzers { 29 namespace ast_fuzzer { 30 31 /// The base class for all the mutations in the fuzzer. Children must override 32 /// three methods: 33 /// - `IsApplicable` - checks whether it is possible to apply the mutation 34 /// in a manner that will lead to a valid program. 35 /// - `Apply` - applies the mutation. 36 /// - `ToMessage` - converts the mutation data into a protobuf message. 37 class Mutation { 38 public: 39 /// Virtual destructor. 40 virtual ~Mutation(); 41 42 /// @brief Determines whether this mutation is applicable to the `program`. 43 /// 44 /// @param program - the program this mutation will be applied to. The program 45 /// must be valid. 46 /// @param node_id_map - the map from `tint::ast::` nodes to their ids. 47 /// @return `true` if `Apply` method can be called without breaking the 48 /// semantics of the `program`. 49 /// @return `false` otherwise. 50 virtual bool IsApplicable(const tint::Program& program, 51 const NodeIdMap& node_id_map) const = 0; 52 53 /// @brief Applies this mutation to the `clone_context`. 54 /// 55 /// Precondition: `IsApplicable` must return `true` when invoked on the same 56 /// `node_id_map` and `clone_context->src` instance of `tint::Program`. A new 57 /// `tint::Program` that arises in `clone_context` must be valid. 58 /// 59 /// @param node_id_map - the map from `tint::ast::` nodes to their ids. 60 /// @param clone_context - the context that will clone the program with some 61 /// changes introduced by this mutation. 62 /// @param new_node_id_map - this map will store ids for the mutated and 63 /// cloned program. This argument cannot be a `nullptr` nor can it point 64 /// to the same object as `node_id_map`. 65 virtual void Apply(const NodeIdMap& node_id_map, 66 tint::CloneContext* clone_context, 67 NodeIdMap* new_node_id_map) const = 0; 68 69 /// @return a protobuf message for this mutation. 70 virtual protobufs::Mutation ToMessage() const = 0; 71 72 /// @brief Converts a protobuf message into the mutation instance. 73 /// 74 /// @param message - a protobuf message. 75 /// @return the instance of this class. 76 static std::unique_ptr<Mutation> FromMessage( 77 const protobufs::Mutation& message); 78 }; 79 80 using MutationList = std::vector<std::unique_ptr<Mutation>>; 81 82 } // namespace ast_fuzzer 83 } // namespace fuzzers 84 } // namespace tint 85 86 #endif // FUZZERS_TINT_AST_FUZZER_MUTATION_H_ 87