Coverage Report

Created: 2022-05-14 11:35

/Users/buildslave/jenkins/workspace/coverage/llvm-project/clang/include/clang/Tooling/DependencyScanning/ModuleDepCollector.h
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//===- ModuleDepCollector.h - Callbacks to collect deps ---------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_CLANG_TOOLING_DEPENDENCYSCANNING_MODULEDEPCOLLECTOR_H
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#define LLVM_CLANG_TOOLING_DEPENDENCYSCANNING_MODULEDEPCOLLECTOR_H
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#include "clang/Basic/LLVM.h"
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#include "clang/Basic/SourceManager.h"
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#include "clang/Frontend/CompilerInvocation.h"
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#include "clang/Frontend/Utils.h"
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#include "clang/Lex/HeaderSearch.h"
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#include "clang/Lex/PPCallbacks.h"
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#include "clang/Serialization/ASTReader.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/StringSet.h"
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#include "llvm/Support/raw_ostream.h"
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#include <string>
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#include <unordered_map>
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namespace clang {
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namespace tooling {
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namespace dependencies {
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class DependencyConsumer;
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/// Modular dependency that has already been built prior to the dependency scan.
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struct PrebuiltModuleDep {
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  std::string ModuleName;
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  std::string PCMFile;
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  std::string ModuleMapFile;
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  explicit PrebuiltModuleDep(const Module *M)
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      : ModuleName(M->getTopLevelModuleName()),
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        PCMFile(M->getASTFile()->getName()),
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        ModuleMapFile(M->PresumedModuleMapFile) {}
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};
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/// This is used to identify a specific module.
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struct ModuleID {
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  /// The name of the module. This may include `:` for C++20 module partitions,
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  /// or a header-name for C++20 header units.
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  std::string ModuleName;
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  /// The context hash of a module represents the set of compiler options that
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  /// may make one version of a module incompatible with another. This includes
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  /// things like language mode, predefined macros, header search paths, etc...
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  ///
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  /// Modules with the same name but a different \c ContextHash should be
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  /// treated as separate modules for the purpose of a build.
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  std::string ContextHash;
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  bool operator==(const ModuleID &Other) const {
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    return ModuleName == Other.ModuleName && 
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;
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  }
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};
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struct ModuleIDHasher {
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  std::size_t operator()(const ModuleID &MID) const {
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    return llvm::hash_combine(MID.ModuleName, MID.ContextHash);
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  }
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};
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struct ModuleDeps {
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  /// The identifier of the module.
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  ModuleID ID;
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  /// Whether this is a "system" module.
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  bool IsSystem;
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  /// The path to the modulemap file which defines this module.
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  ///
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  /// This can be used to explicitly build this module. This file will
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  /// additionally appear in \c FileDeps as a dependency.
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  std::string ClangModuleMapFile;
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  /// The path to where an implicit build would put the PCM for this module.
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  std::string ImplicitModulePCMPath;
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  /// A collection of absolute paths to files that this module directly depends
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  /// on, not including transitive dependencies.
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  llvm::StringSet<> FileDeps;
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  /// A collection of absolute paths to module map files that this module needs
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  /// to know about.
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  std::vector<std::string> ModuleMapFileDeps;
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  /// A collection of prebuilt modular dependencies this module directly depends
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  /// on, not including transitive dependencies.
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  std::vector<PrebuiltModuleDep> PrebuiltModuleDeps;
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  /// A list of module identifiers this module directly depends on, not
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  /// including transitive dependencies.
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  ///
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  /// This may include modules with a different context hash when it can be
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  /// determined that the differences are benign for this compilation.
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  std::vector<ModuleID> ClangModuleDeps;
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  // Used to track which modules that were discovered were directly imported by
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  // the primary TU.
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  bool ImportedByMainFile = false;
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  /// Compiler invocation that can be used to build this module (without paths).
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  CompilerInvocation BuildInvocation;
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  /// Gets the canonical command line suitable for passing to clang.
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  ///
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  /// \param LookupPCMPath This function is called to fill in "-fmodule-file="
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  ///                      arguments and the "-o" argument. It needs to return
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  ///                      a path for where the PCM for the given module is to
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  ///                      be located.
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  std::vector<std::string> getCanonicalCommandLine(
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      std::function<StringRef(ModuleID)> LookupPCMPath) const;
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  /// Gets the canonical command line suitable for passing to clang, excluding
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  /// "-fmodule-file=" and "-o" arguments.
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  std::vector<std::string> getCanonicalCommandLineWithoutModulePaths() const;
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};
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class ModuleDepCollector;
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/// Callback that records textual includes and direct modular includes/imports
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/// during preprocessing. At the end of the main file, it also collects
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/// transitive modular dependencies and passes everything to the
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/// \c DependencyConsumer of the parent \c ModuleDepCollector.
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class ModuleDepCollectorPP final : public PPCallbacks {
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public:
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  ModuleDepCollectorPP(ModuleDepCollector &MDC) : MDC(MDC) {}
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  void FileChanged(SourceLocation Loc, FileChangeReason Reason,
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                   SrcMgr::CharacteristicKind FileType,
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                   FileID PrevFID) override;
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  void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,
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                          StringRef FileName, bool IsAngled,
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                          CharSourceRange FilenameRange,
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                          Optional<FileEntryRef> File, StringRef SearchPath,
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                          StringRef RelativePath, const Module *Imported,
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                          SrcMgr::CharacteristicKind FileType) override;
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  void moduleImport(SourceLocation ImportLoc, ModuleIdPath Path,
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                    const Module *Imported) override;
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  void EndOfMainFile() override;
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private:
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  /// The parent dependency collector.
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  ModuleDepCollector &MDC;
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  /// Working set of direct modular dependencies.
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  llvm::DenseSet<const Module *> DirectModularDeps;
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  /// Working set of direct modular dependencies that have already been built.
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  llvm::DenseSet<const Module *> DirectPrebuiltModularDeps;
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  void handleImport(const Module *Imported);
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  /// Adds direct modular dependencies that have already been built to the
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  /// ModuleDeps instance.
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  void
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  addAllSubmodulePrebuiltDeps(const Module *M, ModuleDeps &MD,
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                              llvm::DenseSet<const Module *> &SeenSubmodules);
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  void addModulePrebuiltDeps(const Module *M, ModuleDeps &MD,
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                             llvm::DenseSet<const Module *> &SeenSubmodules);
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  /// Traverses the previously collected direct modular dependencies to discover
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  /// transitive modular dependencies and fills the parent \c ModuleDepCollector
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  /// with both.
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  ModuleID handleTopLevelModule(const Module *M);
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  void addAllSubmoduleDeps(const Module *M, ModuleDeps &MD,
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                           llvm::DenseSet<const Module *> &AddedModules);
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  void addModuleDep(const Module *M, ModuleDeps &MD,
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                    llvm::DenseSet<const Module *> &AddedModules);
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};
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/// Collects modular and non-modular dependencies of the main file by attaching
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/// \c ModuleDepCollectorPP to the preprocessor.
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class ModuleDepCollector final : public DependencyCollector {
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public:
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  ModuleDepCollector(std::unique_ptr<DependencyOutputOptions> Opts,
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                     CompilerInstance &ScanInstance, DependencyConsumer &C,
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                     CompilerInvocation &&OriginalCI, bool OptimizeArgs);
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  void attachToPreprocessor(Preprocessor &PP) override;
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  void attachToASTReader(ASTReader &R) override;
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private:
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  friend ModuleDepCollectorPP;
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  /// The compiler instance for scanning the current translation unit.
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  CompilerInstance &ScanInstance;
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  /// The consumer of collected dependency information.
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  DependencyConsumer &Consumer;
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  /// Path to the main source file.
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  std::string MainFile;
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  /// Hash identifying the compilation conditions of the current TU.
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  std::string ContextHash;
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  /// Non-modular file dependencies. This includes the main source file and
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  /// textually included header files.
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  std::vector<std::string> FileDeps;
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  /// Direct and transitive modular dependencies of the main source file.
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  std::unordered_map<const Module *, ModuleDeps> ModularDeps;
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  /// Options that control the dependency output generation.
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  std::unique_ptr<DependencyOutputOptions> Opts;
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  /// The original Clang invocation passed to dependency scanner.
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  CompilerInvocation OriginalInvocation;
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  /// Whether to optimize the modules' command-line arguments.
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  bool OptimizeArgs;
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  /// Checks whether the module is known as being prebuilt.
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  bool isPrebuiltModule(const Module *M);
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  /// Constructs a CompilerInvocation that can be used to build the given
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  /// module, excluding paths to discovered modular dependencies that are yet to
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  /// be built.
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  CompilerInvocation makeInvocationForModuleBuildWithoutPaths(
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      const ModuleDeps &Deps,
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      llvm::function_ref<void(CompilerInvocation &)> Optimize) const;
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};
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} // end namespace dependencies
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} // end namespace tooling
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} // end namespace clang
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#endif // LLVM_CLANG_TOOLING_DEPENDENCYSCANNING_MODULEDEPCOLLECTOR_H