1 /* Copyright 2021 The TensorFlow Authors. All Rights Reserved. 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 16 #ifndef TENSORFLOW_COMPILER_MLIR_TENSORFLOW_UTILS_RESOURCE_VALUE_TYPED_ANALYZER_H_ 17 #define TENSORFLOW_COMPILER_MLIR_TENSORFLOW_UTILS_RESOURCE_VALUE_TYPED_ANALYZER_H_ 18 19 #include "llvm/ADT/DenseMap.h" 20 #include "llvm/ADT/StringRef.h" 21 #include "mlir/Dialect/Func/IR/FuncOps.h" // from @llvm-project 22 #include "mlir/IR/BuiltinOps.h" // from @llvm-project 23 24 namespace mlir { 25 namespace TF { 26 27 class ResourceAnalyzer { 28 public: 29 explicit ResourceAnalyzer(ModuleOp module, bool skip_session_init = false); 30 31 bool IsPotentiallyWritten(Value resource) const; 32 33 private: 34 // Analyze the specified region for resource mutating operations, namely 35 // TF::AssignVariableOp, if so, set the resource associated as "potentially 36 // written". 37 LogicalResult AnalyzeRegion(Region& region); 38 39 // If an op is not one of the handled ones, we assume all resource usages 40 // within its purview are mutating in nature. 41 void PropagatePotentiallyWrittenWithinUnhandledOp(Operation* op); 42 43 // Given a Region associated with the callee and operands from the 44 // corresponding callOp, propagate the potentially written decision to the 45 // callOp's operands, if the corresponding region's arguments are potentially 46 // written resources. 47 void PropagatePotentiallyWrittenUpFromCallee( 48 Region& region, Operation::operand_range propagate_to); 49 50 // Marks 'resource' as written. 51 void SetPotentiallyWritten(Value resource); 52 53 struct ResourceInfo { 54 bool potentially_written = false; 55 }; 56 // Key: Resource Value's 57 // Value: Information we know about that Value. 58 // Note that these Value's are in general in different functions. 59 DenseMap<Value, ResourceInfo> resource_infos_; 60 // The set of regions we already discovered. 61 DenseSet<Region*> discovered_; 62 // Identifiers about mutable variables. 63 // All variables are identified by (device, container, shared_name). 64 DenseSet<std::tuple<llvm::StringRef, llvm::StringRef, llvm::StringRef>> 65 mutable_variables_; 66 }; 67 68 } // namespace TF 69 } // namespace mlir 70 71 #endif // TENSORFLOW_COMPILER_MLIR_TENSORFLOW_UTILS_RESOURCE_VALUE_TYPED_ANALYZER_H_ 72