1 //===--- MacroPPCallbacks.h -------------------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 //  This file defines implementation for the macro preprocessors callbacks.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CLANG_LIB_CODEGEN_MACROPPCALLBACKS_H
14 #define LLVM_CLANG_LIB_CODEGEN_MACROPPCALLBACKS_H
15 
16 #include "clang/Lex/PPCallbacks.h"
17 
18 namespace llvm {
19 class DIMacroFile;
20 }
21 namespace clang {
22 class Preprocessor;
23 class MacroInfo;
24 class CodeGenerator;
25 
26 class MacroPPCallbacks : public PPCallbacks {
27   /// A pointer to code generator, where debug info generator can be found.
28   CodeGenerator *Gen;
29 
30   /// Preprocessor.
31   Preprocessor &PP;
32 
33   /// Location of recent included file, used for line number.
34   SourceLocation LastHashLoc;
35 
36   /// Counts current number of command line included files, which were entered
37   /// and were not exited yet.
38   int EnteredCommandLineIncludeFiles = 0;
39 
40   enum FileScopeStatus {
41     NoScope = 0,              // Scope is not initialized yet.
42     InitializedScope,         // Main file scope is initialized but not set yet.
43     BuiltinScope,             // <built-in> and <command line> file scopes.
44     CommandLineIncludeScope,  // Included file, from <command line> file, scope.
45     MainFileScope             // Main file scope.
46   };
47   FileScopeStatus Status;
48 
49   /// Parent contains all entered files that were not exited yet according to
50   /// the inclusion order.
51   llvm::SmallVector<llvm::DIMacroFile *, 4> Scopes;
52 
53   /// Get current DIMacroFile scope.
54   /// \return current DIMacroFile scope or nullptr if there is no such scope.
55   llvm::DIMacroFile *getCurrentScope();
56 
57   /// Get current line location or invalid location.
58   /// \param Loc current line location.
59   /// \return current line location \p `Loc`, or invalid location if it's in a
60   ///         skipped file scope.
61   SourceLocation getCorrectLocation(SourceLocation Loc);
62 
63   /// Use the passed preprocessor to write the macro name and value from the
64   /// given macro info and identifier info into the given \p `Name` and \p
65   /// `Value` output streams.
66   ///
67   /// \param II Identifier info, used to get the Macro name.
68   /// \param MI Macro info, used to get the Macro argumets and values.
69   /// \param PP Preprocessor.
70   /// \param [out] Name Place holder for returned macro name and arguments.
71   /// \param [out] Value Place holder for returned macro value.
72   static void writeMacroDefinition(const IdentifierInfo &II,
73                                    const MacroInfo &MI, Preprocessor &PP,
74                                    raw_ostream &Name, raw_ostream &Value);
75 
76   /// Update current file scope status to next file scope.
77   void updateStatusToNextScope();
78 
79   /// Handle the case when entering a file.
80   ///
81   /// \param Loc Indicates the new location.
82   void FileEntered(SourceLocation Loc);
83 
84   /// Handle the case when exiting a file.
85   ///
86   /// \param Loc Indicates the new location.
87   void FileExited(SourceLocation Loc);
88 
89 public:
90   MacroPPCallbacks(CodeGenerator *Gen, Preprocessor &PP);
91 
92   /// Callback invoked whenever a source file is entered or exited.
93   ///
94   /// \param Loc Indicates the new location.
95   /// \param PrevFID the file that was exited if \p Reason is ExitFile.
96   void FileChanged(SourceLocation Loc, FileChangeReason Reason,
97                    SrcMgr::CharacteristicKind FileType,
98                    FileID PrevFID = FileID()) override;
99 
100   /// Callback invoked whenever a directive (#xxx) is processed.
101   void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,
102                           StringRef FileName, bool IsAngled,
103                           CharSourceRange FilenameRange, const FileEntry *File,
104                           StringRef SearchPath, StringRef RelativePath,
105                           const Module *Imported,
106                           SrcMgr::CharacteristicKind FileType) override;
107 
108   /// Hook called whenever a macro definition is seen.
109   void MacroDefined(const Token &MacroNameTok,
110                     const MacroDirective *MD) override;
111 
112   /// Hook called whenever a macro \#undef is seen.
113   ///
114   /// MD is released immediately following this callback.
115   void MacroUndefined(const Token &MacroNameTok, const MacroDefinition &MD,
116                       const MacroDirective *Undef) override;
117 };
118 
119 } // end namespace clang
120 
121 #endif
122