CodeGenAction.h

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//===--- CodeGenAction.h - LLVM Code Generation Frontend Action -*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
 
#ifndef LLVM_CLANG_CODEGEN_CODEGENACTION_H
#define LLVM_CLANG_CODEGEN_CODEGENACTION_H
 
#include "clang/Frontend/FrontendAction.h"
#include <memory>
 
namespace llvm {
  class LLVMContext;
  class Module;
}
 
namespace clang {
class BackendConsumer;
class CodeGenerator;
 
class CodeGenAction : public ASTFrontendAction {
private:
  // Let BackendConsumer access LinkModule.
  friend class BackendConsumer;
 
  /// Info about module to link into a module we're generating.
  struct LinkModule {
    /// The module to link in.
    std::unique_ptr<llvm::Module> Module;
 
    /// If true, we set attributes on Module's functions according to our
    /// CodeGenOptions and LangOptions, as though we were generating the
    /// function ourselves.
    bool PropagateAttrs;
 
    /// If true, we use LLVM module internalizer.
    bool Internalize;
 
    /// Bitwise combination of llvm::LinkerFlags used when we link the module.
    unsigned LinkFlags;
  };
 
  unsigned Act;
  std::unique_ptr<llvm::Module> TheModule;
 
  /// Bitcode modules to link in to our module.
  SmallVector<LinkModule, 4> LinkModules;
  llvm::LLVMContext *VMContext;
  bool OwnsVMContext;
 
  std::unique_ptr<llvm::Module> loadModule(llvm::MemoryBufferRef MBRef);
 
  /// Load bitcode modules to link into our module from the options.
  bool loadLinkModules(CompilerInstance &CI);
 
protected:
  bool BeginSourceFileAction(CompilerInstance &CI) override;
 
  /// Create a new code generation action.  If the optional \p _VMContext
  /// parameter is supplied, the action uses it without taking ownership,
  /// otherwise it creates a fresh LLVM context and takes ownership.
  CodeGenAction(unsigned _Act, llvm::LLVMContext *_VMContext = nullptr);
 
  bool hasIRSupport() const override;
 
  std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &CI,
                                                 StringRef InFile) override;
 
  void ExecuteAction() override;
 
  void EndSourceFileAction() override;
 
public:
  ~CodeGenAction() override;
 
  /// Take the generated LLVM module, for use after the action has been run.
  /// The result may be null on failure.
  std::unique_ptr<llvm::Module> takeModule();
 
  /// Take the LLVM context used by this action.
  llvm::LLVMContext *takeLLVMContext();
 
  CodeGenerator *getCodeGenerator() const;
 
  BackendConsumer *BEConsumer = nullptr;
};