llvm-project/clang-tools-extra/modularize/PreprocessorTracker.h

70 lines
2.8 KiB
C++

//===- PreprocessorTracker.h - Tracks preprocessor activities -*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===--------------------------------------------------------------------===//
///
/// \file
/// \brief Macro expansions and preprocessor conditional consistency checker.
///
//===--------------------------------------------------------------------===//
#ifndef MODULARIZE_PREPROCESSOR_TRACKER_H
#define MODULARIZE_PREPROCESSOR_TRACKER_H
#include "clang/Lex/Preprocessor.h"
namespace Modularize {
/// \brief Preprocessor tracker for modularize.
///
/// The PreprocessorTracker class defines an API for
/// checking macro expansions and preprocessor conditional expressions
/// in a header file for consistency among one or more compilations of
/// the header in a #include scenario. This is for helping a user
/// find which macro expansions or conditionals might be problematic with
/// respect to using the headers in the modules scenario, because they
/// evaluate to different values depending on how or where a header
/// is included.
///
/// The handlePreprocessorEntry function implementation will register
/// a PPCallbacks object in the given Preprocessor object. The calls to
/// the callbacks will collect information about the macro expansions
/// and preprocessor conditionals encountered, for later analysis and
/// reporting of inconsistencies between runs performed by calls to
/// the reportInconsistentMacros and reportInconsistentConditionals
/// functions respectively. The handlePreprocessorExit informs the
/// implementation that a preprocessing session is complete, allowing
/// it to do any needed compilation completion activities in the checker.
class PreprocessorTracker {
public:
virtual ~PreprocessorTracker();
// Handle entering a preprocessing session.
// (Called after a Preprocessor object is created, but before preprocessing.)
virtual void handlePreprocessorEntry(clang::Preprocessor &PP,
llvm::StringRef RootHeaderFile) = 0;
// Handle exiting a preprocessing session.
// (Called after preprocessing is complete, but before the Preprocessor
// object is destroyed.)
virtual void handlePreprocessorExit() = 0;
// Report on inconsistent macro instances.
// Returns true if any mismatches.
virtual bool reportInconsistentMacros(llvm::raw_ostream &OS) = 0;
// Report on inconsistent conditional directive instances.
// Returns true if any mismatches.
virtual bool reportInconsistentConditionals(llvm::raw_ostream &OS) = 0;
// Create instance of PreprocessorTracker.
static PreprocessorTracker *create();
};
} // end namespace Modularize
#endif