Subversion Repositories QNX 8.QNX8 LLVM/Clang compiler suite

//===-- llvm/IR/ModuleSlotTracker.h -----------------------------*- 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_IR_MODULESLOTTRACKER_H

#define LLVM_IR_MODULESLOTTRACKER_H

#include <functional>

#include <memory>

#include <utility>

#include <vector>

namespace llvm {

class Module;

class Function;

class SlotTracker;

class Value;

class MDNode;

/// Abstract interface of slot tracker storage.

class AbstractSlotTrackerStorage {

public:

  virtual ~AbstractSlotTrackerStorage();

  virtual unsigned getNextMetadataSlot() = 0;

  virtual void createMetadataSlot(const MDNode *) = 0;

  virtual int getMetadataSlot(const MDNode *) = 0;

};

/// Manage lifetime of a slot tracker for printing IR.

///

/// Wrapper around the \a SlotTracker used internally by \a AsmWriter.  This

/// class allows callers to share the cost of incorporating the metadata in a

/// module or a function.

///

/// If the IR changes from underneath \a ModuleSlotTracker, strings like

/// "<badref>" will be printed, or, worse, the wrong slots entirely.

class ModuleSlotTracker {

  /// Storage for a slot tracker.

  std::unique_ptr<SlotTracker> MachineStorage;

  bool ShouldCreateStorage = false;

  bool ShouldInitializeAllMetadata = false;

  const Module *M = nullptr;

  const Function *F = nullptr;

  SlotTracker *Machine = nullptr;

  std::function<void(AbstractSlotTrackerStorage *, const Module *, bool)>

      ProcessModuleHookFn;

  std::function<void(AbstractSlotTrackerStorage *, const Function *, bool)>

      ProcessFunctionHookFn;

public:

  /// Wrap a preinitialized SlotTracker.

  ModuleSlotTracker(SlotTracker &Machine, const Module *M,

                    const Function *F = nullptr);

  /// Construct a slot tracker from a module.

  ///

  /// If \a M is \c nullptr, uses a null slot tracker.  Otherwise, initializes

  /// a slot tracker, and initializes all metadata slots.  \c

  /// ShouldInitializeAllMetadata defaults to true because this is expected to

  /// be shared between multiple callers, and otherwise MDNode references will

  /// not match up.

  explicit ModuleSlotTracker(const Module *M,

                             bool ShouldInitializeAllMetadata = true);

  /// Destructor to clean up storage.

  virtual ~ModuleSlotTracker();

  /// Lazily creates a slot tracker.

  SlotTracker *getMachine();

  const Module *getModule() const { return M; }

  const Function *getCurrentFunction() const { return F; }

  /// Incorporate the given function.

  ///

  /// Purge the currently incorporated function and incorporate \c F.  If \c F

  /// is currently incorporated, this is a no-op.

  void incorporateFunction(const Function &F);

  /// Return the slot number of the specified local value.

  ///

  /// A function that defines this value should be incorporated prior to calling

  /// this method.

  /// Return -1 if the value is not in the function's SlotTracker.

  int getLocalSlot(const Value *V);

  void setProcessHook(

      std::function<void(AbstractSlotTrackerStorage *, const Module *, bool)>);

  void setProcessHook(std::function<void(AbstractSlotTrackerStorage *,

                                         const Function *, bool)>);

  using MachineMDNodeListType =

      std::vector<std::pair<unsigned, const MDNode *>>;

  void collectMDNodes(MachineMDNodeListType &L, unsigned LB, unsigned UB) const;

};

} // end namespace llvm

#endif