//===--- Execution.h - Executing clang frontend actions -*- 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
 
//
 
//===----------------------------------------------------------------------===//
 
//
 
//  This file defines framework for executing clang frontend actions.
 
//
 
//  The framework can be extended to support different execution plans including
 
//  standalone execution on the given TUs or parallel execution on all TUs in
 
//  the codebase.
 
//
 
//  In order to enable multiprocessing execution, tool actions are expected to
 
//  output result into the ToolResults provided by the executor. The
 
//  `ToolResults` is an interface that abstracts how results are stored e.g.
 
//  in-memory for standalone execution or on-disk for large-scale execution.
 
//
 
//  New executors can be registered as ToolExecutorPlugins via the
 
//  `ToolExecutorPluginRegistry`. CLI tools can use
 
//  `createExecutorFromCommandLineArgs` to create a specific registered executor
 
//  according to the command-line arguments.
 
//
 
//===----------------------------------------------------------------------===//
 
 
 
#ifndef LLVM_CLANG_TOOLING_EXECUTION_H
 
#define LLVM_CLANG_TOOLING_EXECUTION_H
 
 
 
#include "clang/Tooling/CommonOptionsParser.h"
 
#include "clang/Tooling/Tooling.h"
 
#include "llvm/Support/Error.h"
 
#include "llvm/Support/Registry.h"
 
#include "llvm/Support/StringSaver.h"
 
 
 
namespace clang {
 
namespace tooling {
 
 
 
extern llvm::cl::opt<std::string> ExecutorName;
 
 
 
/// An abstraction for the result of a tool execution. For example, the
 
/// underlying result can be in-memory or on-disk.
 
///
 
/// Results should be string key-value pairs. For example, a refactoring tool
 
/// can use source location as key and a replacement in YAML format as value.
 
class ToolResults {
 
public:
 
  virtual ~ToolResults() = default;
 
  virtual void addResult(StringRef Key, StringRef Value) = 0;
 
  virtual std::vector<std::pair<llvm::StringRef, llvm::StringRef>>
 
  AllKVResults() = 0;
 
  virtual void forEachResult(
 
      llvm::function_ref<void(StringRef Key, StringRef Value)> Callback) = 0;
 
};
 
 
 
/// Stores the key-value results in memory. It maintains the lifetime of
 
/// the result. Clang tools using this class are expected to generate a small
 
/// set of different results, or a large set of duplicated results.
 
class InMemoryToolResults : public ToolResults {
 
public:
 
  InMemoryToolResults() : Strings(Arena) {}
 
  void addResult(StringRef Key, StringRef Value) override;
 
  std::vector<std::pair<llvm::StringRef, llvm::StringRef>>
 
  AllKVResults() override;
 
  void forEachResult(llvm::function_ref<void(StringRef Key, StringRef Value)>
 
                         Callback) override;
 
 
 
private:
 
  llvm::BumpPtrAllocator Arena;
 
  llvm::UniqueStringSaver Strings;
 
 
 
  std::vector<std::pair<llvm::StringRef, llvm::StringRef>> KVResults;
 
};
 
 
 
/// The context of an execution, including the information about
 
/// compilation and results.
 
class ExecutionContext {
 
public:
 
  virtual ~ExecutionContext() {}
 
 
 
  /// Initializes a context. This does not take ownership of `Results`.
 
  explicit ExecutionContext(ToolResults *Results) : Results(Results) {}
 
 
 
  /// Adds a KV pair to the result container of this execution.
 
  void reportResult(StringRef Key, StringRef Value);
 
 
 
  // Returns the source control system's revision number if applicable.
 
  // Otherwise returns an empty string.
 
  virtual std::string getRevision() { return ""; }
 
 
 
  // Returns the corpus being analyzed, e.g. "llvm" for the LLVM codebase, if
 
  // applicable.
 
  virtual std::string getCorpus() { return ""; }
 
 
 
  // Returns the currently processed compilation unit if available.
 
  virtual std::string getCurrentCompilationUnit() { return ""; }
 
 
 
private:
 
  ToolResults *Results;
 
};
 
 
 
/// Interface for executing clang frontend actions.
 
///
 
/// This can be extended to support running tool actions in different
 
/// execution mode, e.g. on a specific set of TUs or many TUs in parallel.
 
///
 
///  New executors can be registered as ToolExecutorPlugins via the
 
///  `ToolExecutorPluginRegistry`. CLI tools can use
 
///  `createExecutorFromCommandLineArgs` to create a specific registered
 
///  executor according to the command-line arguments.
 
class ToolExecutor {
 
public:
 
  virtual ~ToolExecutor() {}
 
 
 
  /// Returns the name of a specific executor.
 
  virtual StringRef getExecutorName() const = 0;
 
 
 
  /// Executes each action with a corresponding arguments adjuster.
 
  virtual llvm::Error
 
  execute(llvm::ArrayRef<
 
          std::pair<std::unique_ptr<FrontendActionFactory>, ArgumentsAdjuster>>
 
              Actions) = 0;
 
 
 
  /// Convenient functions for the above `execute`.
 
  llvm::Error execute(std::unique_ptr<FrontendActionFactory> Action);
 
  /// Executes an action with an argument adjuster.
 
  llvm::Error execute(std::unique_ptr<FrontendActionFactory> Action,
 
                      ArgumentsAdjuster Adjuster);
 
 
 
  /// Returns a reference to the execution context.
 
  ///
 
  /// This should be passed to tool callbacks, and tool callbacks should report
 
  /// results via the returned context.
 
  virtual ExecutionContext *getExecutionContext() = 0;
 
 
 
  /// Returns a reference to the result container.
 
  ///
 
  /// NOTE: This should only be used after the execution finishes. Tool
 
  /// callbacks should report results via `ExecutionContext` instead.
 
  virtual ToolResults *getToolResults() = 0;
 
 
 
  /// Map a virtual file to be used while running the tool.
 
  ///
 
  /// \param FilePath The path at which the content will be mapped.
 
  /// \param Content A buffer of the file's content.
 
  virtual void mapVirtualFile(StringRef FilePath, StringRef Content) = 0;
 
};
 
 
 
/// Interface for factories that create specific executors. This is also
 
/// used as a plugin to be registered into ToolExecutorPluginRegistry.
 
class ToolExecutorPlugin {
 
public:
 
  virtual ~ToolExecutorPlugin() {}
 
 
 
  /// Create an `ToolExecutor`.
 
  ///
 
  /// `OptionsParser` can be consumed (e.g. moved) if the creation succeeds.
 
  virtual llvm::Expected<std::unique_ptr<ToolExecutor>>
 
  create(CommonOptionsParser &OptionsParser) = 0;
 
};
 
 
 
/// This creates a ToolExecutor that is in the global registry based on
 
/// commandline arguments.
 
///
 
/// This picks the right executor based on the `--executor` option. This parses
 
/// the commandline arguments with `CommonOptionsParser`, so caller does not
 
/// need to parse again.
 
///
 
/// By default, this creates a `StandaloneToolExecutor` ("standalone") if
 
/// `--executor` is not provided.
 
llvm::Expected<std::unique_ptr<ToolExecutor>>
 
createExecutorFromCommandLineArgs(int &argc, const char **argv,
 
                                  llvm::cl::OptionCategory &Category,
 
                                  const char *Overview = nullptr);
 
 
 
namespace internal {
 
llvm::Expected<std::unique_ptr<ToolExecutor>>
 
createExecutorFromCommandLineArgsImpl(int &argc, const char **argv,
 
                                      llvm::cl::OptionCategory &Category,
 
                                      const char *Overview = nullptr);
 
} // end namespace internal
 
 
 
} // end namespace tooling
 
} // end namespace clang
 
 
 
#endif // LLVM_CLANG_TOOLING_EXECUTION_H