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 SRC_SEM_INFO_H_ 16 #define SRC_SEM_INFO_H_ 17 18 #include <type_traits> 19 #include <unordered_map> 20 21 #include "src/debug.h" 22 #include "src/sem/node.h" 23 #include "src/sem/type_mappings.h" 24 25 namespace tint { 26 namespace sem { 27 28 /// Info holds all the resolved semantic information for a Program. 29 class Info { 30 public: 31 /// Placeholder type used by Get() to provide a default value for EXPLICIT_SEM 32 using InferFromAST = std::nullptr_t; 33 34 /// Resolves to the return type of the Get() method given the desired sementic 35 /// type and AST type. 36 template <typename SEM, typename AST_OR_TYPE> 37 using GetResultType = 38 std::conditional_t<std::is_same<SEM, InferFromAST>::value, 39 SemanticNodeTypeFor<AST_OR_TYPE>, 40 SEM>; 41 42 /// Constructor 43 Info(); 44 45 /// Move constructor 46 Info(Info&&); 47 48 /// Destructor 49 ~Info(); 50 51 /// Move assignment operator 52 /// @param rhs the Program to move 53 /// @return this Program 54 Info& operator=(Info&& rhs); 55 56 /// Get looks up the semantic information for the AST or type node `node`. 57 /// @param node the AST or type node 58 /// @returns a pointer to the semantic node if found, otherwise nullptr 59 template <typename SEM = InferFromAST, 60 typename AST_OR_TYPE = CastableBase, 61 typename RESULT = GetResultType<SEM, AST_OR_TYPE>> Get(const AST_OR_TYPE * node)62 const RESULT* Get(const AST_OR_TYPE* node) const { 63 auto it = map.find(node); 64 if (it == map.end()) { 65 return nullptr; 66 } 67 return As<RESULT>(it->second); 68 } 69 70 /// Add registers the semantic node `sem_node` for the AST or type node 71 /// `node`. 72 /// @param node the AST or type node 73 /// @param sem_node the semantic node 74 template <typename AST_OR_TYPE> Add(const AST_OR_TYPE * node,const SemanticNodeTypeFor<AST_OR_TYPE> * sem_node)75 void Add(const AST_OR_TYPE* node, 76 const SemanticNodeTypeFor<AST_OR_TYPE>* sem_node) { 77 // Check there's no semantic info already existing for the node 78 TINT_ASSERT(Semantic, Get(node) == nullptr); 79 map.emplace(node, sem_node); 80 } 81 82 /// Wrap returns a new Info created with the contents of `inner`. 83 /// The Info returned by Wrap is intended to temporarily extend the contents 84 /// of an existing immutable Info. 85 /// As the copied contents are owned by `inner`, `inner` must not be 86 /// destructed or assigned while using the returned Info. 87 /// @param inner the immutable Info to extend 88 /// @return the Info that wraps `inner` Wrap(const Info & inner)89 static Info Wrap(const Info& inner) { 90 Info out; 91 out.map = inner.map; 92 return out; 93 } 94 95 private: 96 // TODO(crbug.com/tint/724): Once finished, this map should be: 97 // std::unordered_map<const ast::Node*, const sem::Node*> 98 std::unordered_map<const CastableBase*, const CastableBase*> map; 99 }; 100 101 } // namespace sem 102 } // namespace tint 103 104 #endif // SRC_SEM_INFO_H_ 105