[DebugInfo] Added support to Clang FE for generating debug info for preprocessor macros.

Added "-fdebug-macro" flag (and "-fno-debug-macro" flag) to enable (and to disable) emitting macro debug info.
Added CC1 "-debug-info-macro" flag that enables emitting macro debug info.

Differential Revision: https://reviews.llvm.org/D16135

llvm-svn: 294637

1 files changed, 118 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/MacroPPCallbacks.h b/clang/lib/CodeGen/MacroPPCallbacks.h
new file mode 100644
index 000000000000..f02801dc3275
--- /dev/null
+++ b/clang/lib/CodeGen/MacroPPCallbacks.h
@@ -0,0 +1,118 @@
+//===--- MacroPPCallbacks.h -------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file defines implementation for the macro preprocessors callbacks.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Lex/PPCallbacks.h"
+
+namespace llvm {
+class DIMacroFile;
+class DIMacroNode;
+}
+namespace clang {
+class Preprocessor;
+class MacroInfo;
+class CodeGenerator;
+
+class MacroPPCallbacks : public PPCallbacks {
+  /// A pointer to code generator, where debug info generator can be found.
+  CodeGenerator *Gen;
+
+  /// Preprocessor.
+  Preprocessor &PP;
+
+  /// Location of recent included file, used for line number.
+  SourceLocation LastHashLoc;
+
+  /// Counts current number of command line included files, which were entered
+  /// and were not exited yet.
+  int EnteredCommandLineIncludeFiles = 0;
+
+  enum FileScopeStatus {
+    NoScope = 0,              // Scope is not initialized yet.
+    InitializedScope,         // Main file scope is initialized but not set yet.
+    BuiltinScope,             // <built-in> and <command line> file scopes.
+    CommandLineIncludeScope,  // Included file, from <command line> file, scope.
+    MainFileScope             // Main file scope.
+  };
+  FileScopeStatus Status;
+
+  /// Parent contains all entered files that were not exited yet according to
+  /// the inclusion order.
+  llvm::SmallVector<llvm::DIMacroFile *, 4> Scopes;
+
+  /// Get current DIMacroFile scope.
+  /// \return current DIMacroFile scope or nullptr if there is no such scope.
+  llvm::DIMacroFile *getCurrentScope();
+
+  /// Get current line location or invalid location.
+  /// \param Loc current line location.
+  /// \return current line location \p `Loc`, or invalid location if it's in a
+  ///         skipped file scope.
+  SourceLocation getCorrectLocation(SourceLocation Loc);
+
+  /// Use the passed preprocessor to write the macro name and value from the
+  /// given macro info and identifier info into the given \p `Name` and \p
+  /// `Value` output streams.
+  ///
+  /// \param II Identifier info, used to get the Macro name.
+  /// \param MI Macro info, used to get the Macro argumets and values.
+  /// \param PP Preprocessor.
+  /// \param [out] Name Place holder for returned macro name and arguments.
+  /// \param [out] Value Place holder for returned macro value.
+  static void writeMacroDefinition(const IdentifierInfo &II,
+                                   const MacroInfo &MI, Preprocessor &PP,
+                                   raw_ostream &Name, raw_ostream &Value);
+
+  /// Update current file scope status to next file scope.
+  void updateStatusToNextScope();
+
+  /// Handle the case when entering a file.
+  ///
+  /// \param Loc Indicates the new location.
+  /// \Return true if file scope status should be updated.
+  void FileEntered(SourceLocation Loc);
+
+  /// Handle the case when exiting a file.
+  ///
+  /// \Return true if file scope status should be updated.
+  void FileExited(SourceLocation Loc);
+
+public:
+  MacroPPCallbacks(CodeGenerator *Gen, Preprocessor &PP);
+
+  /// Callback invoked whenever a source file is entered or exited.
+  ///
+  /// \param Loc Indicates the new location.
+  /// \param PrevFID the file that was exited if \p Reason is ExitFile.
+  void FileChanged(SourceLocation Loc, FileChangeReason Reason,
+                   SrcMgr::CharacteristicKind FileType,
+                   FileID PrevFID = FileID()) override;
+
+  /// Callback invoked whenever a directive (#xxx) is processed.
+  void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,
+                          StringRef FileName, bool IsAngled,
+                          CharSourceRange FilenameRange, const FileEntry *File,
+                          StringRef SearchPath, StringRef RelativePath,
+                          const Module *Imported) override;
+
+  /// Hook called whenever a macro definition is seen.
+  void MacroDefined(const Token &MacroNameTok,
+                    const MacroDirective *MD) override;
+
+  /// Hook called whenever a macro \#undef is seen.
+  ///
+  /// MD is released immediately following this callback.
+  void MacroUndefined(const Token &MacroNameTok,
+                      const MacroDefinition &MD) override;
+};
+
+} // end namespace clang