text: // Copyright (c) 2017 Google Inc.
  //
  // 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.
  
  #ifndef SOURCE_OPT_FEATURE_MANAGER_H_
  #define SOURCE_OPT_FEATURE_MANAGER_H_
  
  #include "source/assembly_grammar.h"
  #include "source/extensions.h"
  #include "source/opt/module.h"
  
  namespace spvtools {
  namespace opt {
  
  // Tracks features enabled by a module. The IRContext has a FeatureManager.
  class FeatureManager {
   public:
    explicit FeatureManager(const AssemblyGrammar& grammar) : grammar_(grammar) {}
  
    // Returns true if |ext| is an enabled extension in the module.
    bool HasExtension(Extension ext) const { return extensions_.Contains(ext); }
  
    // Removes the given |extension| from the current FeatureManager.
    void RemoveExtension(Extension extension);
  
    // Returns true if |cap| is an enabled capability in the module.
    bool HasCapability(SpvCapability cap) const {
      return capabilities_.Contains(cap);
    }
  
    // Removes the given |capability| from the current FeatureManager.
    void RemoveCapability(SpvCapability capability);
  
    // Analyzes |module| and records enabled extensions and capabilities.
    void Analyze(Module* module);
  
    CapabilitySet* GetCapabilities() { return &capabilities_; }
    const CapabilitySet* GetCapabilities() const { return &capabilities_; }
  
    uint32_t GetExtInstImportId_GLSLstd450() const {
      return extinst_importid_GLSLstd450_;
    }
  
    uint32_t GetExtInstImportId_OpenCL100DebugInfo() const {
      return extinst_importid_OpenCL100DebugInfo_;
    }
  
    friend bool operator==(const FeatureManager& a, const FeatureManager& b);
    friend bool operator!=(const FeatureManager& a, const FeatureManager& b) {
      return !(a == b);
    }
  
    // Adds the given |capability| and all implied capabilities into the current
    // FeatureManager.
    void AddCapability(SpvCapability capability);
  
    // Add the extension |ext| to the feature manager.
    void AddExtension(Instruction* ext);
  
    // Analyzes |module| and records imported external instruction sets.
    void AddExtInstImportIds(Module* module);
  
   private:
    // Analyzes |module| and records enabled extensions.
    void AddExtensions(Module* module);
  
    // Analyzes |module| and records enabled capabilities.
    void AddCapabilities(Module* module);
  
    // Auxiliary object for querying SPIR-V grammar facts.
    const AssemblyGrammar& grammar_;
  
    // The enabled extensions.
    ExtensionSet extensions_;
  
    // The enabled capabilities.
    CapabilitySet capabilities_;
  
    // Common external instruction import ids, cached for performance.
    uint32_t extinst_importid_GLSLstd450_ = 0;
  
    // Common OpenCL100DebugInfo external instruction import ids, cached
    // for performance.
    uint32_t extinst_importid_OpenCL100DebugInfo_ = 0;
  };
  
  }  // namespace opt
  }  // namespace spvtools
  
  #endif  // SOURCE_OPT_FEATURE_MANAGER_H_
  