clang  5.0.0
MacroArgs.h
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1 //===--- MacroArgs.h - Formal argument info for Macros ----------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines the MacroArgs interface.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_CLANG_LEX_MACROARGS_H
15 #define LLVM_CLANG_LEX_MACROARGS_H
16 
17 #include "clang/Basic/LLVM.h"
18 #include "clang/Lex/Token.h"
19 #include "llvm/ADT/ArrayRef.h"
20 #include <vector>
21 
22 namespace clang {
23  class MacroInfo;
24  class Preprocessor;
25  class SourceLocation;
26 
27 /// MacroArgs - An instance of this class captures information about
28 /// the formal arguments specified to a function-like macro invocation.
29 class MacroArgs {
30  /// NumUnexpArgTokens - The number of raw, unexpanded tokens for the
31  /// arguments. All of the actual argument tokens are allocated immediately
32  /// after the MacroArgs object in memory. This is all of the arguments
33  /// concatenated together, with 'EOF' markers at the end of each argument.
34  unsigned NumUnexpArgTokens;
35 
36  /// VarargsElided - True if this is a C99 style varargs macro invocation and
37  /// there was no argument specified for the "..." argument. If the argument
38  /// was specified (even empty) or this isn't a C99 style varargs function, or
39  /// if in strict mode and the C99 varargs macro had only a ... argument, this
40  /// is false.
41  bool VarargsElided;
42 
43  /// PreExpArgTokens - Pre-expanded tokens for arguments that need them. Empty
44  /// if not yet computed. This includes the EOF marker at the end of the
45  /// stream.
46  std::vector<std::vector<Token> > PreExpArgTokens;
47 
48  /// StringifiedArgs - This contains arguments in 'stringified' form. If the
49  /// stringified form of an argument has not yet been computed, this is empty.
50  std::vector<Token> StringifiedArgs;
51 
52  /// ArgCache - This is a linked list of MacroArgs objects that the
53  /// Preprocessor owns which we use to avoid thrashing malloc/free.
54  MacroArgs *ArgCache;
55 
56  /// MacroArgs - The number of arguments the invoked macro expects.
57  unsigned NumMacroArgs;
58 
59  MacroArgs(unsigned NumToks, bool varargsElided, unsigned MacroArgs)
60  : NumUnexpArgTokens(NumToks), VarargsElided(varargsElided),
61  ArgCache(nullptr), NumMacroArgs(MacroArgs) {}
62  ~MacroArgs() = default;
63 
64 public:
65  /// MacroArgs ctor function - Create a new MacroArgs object with the specified
66  /// macro and argument info.
67  static MacroArgs *create(const MacroInfo *MI,
68  ArrayRef<Token> UnexpArgTokens,
69  bool VarargsElided, Preprocessor &PP);
70 
71  /// destroy - Destroy and deallocate the memory for this object.
72  ///
73  void destroy(Preprocessor &PP);
74 
75  /// ArgNeedsPreexpansion - If we can prove that the argument won't be affected
76  /// by pre-expansion, return false. Otherwise, conservatively return true.
77  bool ArgNeedsPreexpansion(const Token *ArgTok, Preprocessor &PP) const;
78 
79  /// getUnexpArgument - Return a pointer to the first token of the unexpanded
80  /// token list for the specified formal.
81  ///
82  const Token *getUnexpArgument(unsigned Arg) const;
83 
84  /// getArgLength - Given a pointer to an expanded or unexpanded argument,
85  /// return the number of tokens, not counting the EOF, that make up the
86  /// argument.
87  static unsigned getArgLength(const Token *ArgPtr);
88 
89  /// getPreExpArgument - Return the pre-expanded form of the specified
90  /// argument.
91  const std::vector<Token> &
92  getPreExpArgument(unsigned Arg, const MacroInfo *MI, Preprocessor &PP);
93 
94  /// getStringifiedArgument - Compute, cache, and return the specified argument
95  /// that has been 'stringified' as required by the # operator.
96  const Token &getStringifiedArgument(unsigned ArgNo, Preprocessor &PP,
97  SourceLocation ExpansionLocStart,
98  SourceLocation ExpansionLocEnd);
99 
100  /// getNumMacroArguments - Return the number of arguments the invoked macro
101  /// expects.
102  unsigned getNumMacroArguments() const { return NumMacroArgs; }
103 
104  /// isVarargsElidedUse - Return true if this is a C99 style varargs macro
105  /// invocation and there was no argument specified for the "..." argument. If
106  /// the argument was specified (even empty) or this isn't a C99 style varargs
107  /// function, or if in strict mode and the C99 varargs macro had only a ...
108  /// argument, this returns false.
109  bool isVarargsElidedUse() const { return VarargsElided; }
110 
111  /// StringifyArgument - Implement C99 6.10.3.2p2, converting a sequence of
112  /// tokens into the literal string token that should be produced by the C #
113  /// preprocessor operator. If Charify is true, then it should be turned into
114  /// a character literal for the Microsoft charize (#@) extension.
115  ///
116  static Token StringifyArgument(const Token *ArgToks,
117  Preprocessor &PP, bool Charify,
118  SourceLocation ExpansionLocStart,
119  SourceLocation ExpansionLocEnd);
120 
121 
122  /// deallocate - This should only be called by the Preprocessor when managing
123  /// its freelist.
124  MacroArgs *deallocate();
125 };
126 
127 } // end namespace clang
128 
129 #endif
unsigned getNumMacroArguments() const
getNumMacroArguments - Return the number of arguments the invoked macro expects.
Definition: MacroArgs.h:102
bool isVarargsElidedUse() const
isVarargsElidedUse - Return true if this is a C99 style varargs macro invocation and there was no arg...
Definition: MacroArgs.h:109
Token - This structure provides full information about a lexed token.
Definition: Token.h:35
Forward-declares and imports various common LLVM datatypes that clang wants to use unqualified...
const std::vector< Token > & getPreExpArgument(unsigned Arg, const MacroInfo *MI, Preprocessor &PP)
getPreExpArgument - Return the pre-expanded form of the specified argument.
Definition: MacroArgs.cpp:149
void destroy(Preprocessor &PP)
destroy - Destroy and deallocate the memory for this object.
Definition: MacroArgs.cpp:75
const Token * getUnexpArgument(unsigned Arg) const
getUnexpArgument - Return a pointer to the first token of the unexpanded token list for the specified...
Definition: MacroArgs.cpp:115
const Token & getStringifiedArgument(unsigned ArgNo, Preprocessor &PP, SourceLocation ExpansionLocStart, SourceLocation ExpansionLocEnd)
getStringifiedArgument - Compute, cache, and return the specified argument that has been 'stringified...
Definition: MacroArgs.cpp:299
static Token StringifyArgument(const Token *ArgToks, Preprocessor &PP, bool Charify, SourceLocation ExpansionLocStart, SourceLocation ExpansionLocEnd)
StringifyArgument - Implement C99 6.10.3.2p2, converting a sequence of tokens into the literal string...
Definition: MacroArgs.cpp:196
MacroArgs - An instance of this class captures information about the formal arguments specified to a ...
Definition: MacroArgs.h:29
MacroArgs * deallocate()
deallocate - This should only be called by the Preprocessor when managing its freelist.
Definition: MacroArgs.cpp:90
Encodes a location in the source.
bool ArgNeedsPreexpansion(const Token *ArgTok, Preprocessor &PP) const
ArgNeedsPreexpansion - If we can prove that the argument won't be affected by pre-expansion, return false.
Definition: MacroArgs.cpp:133
static unsigned getArgLength(const Token *ArgPtr)
getArgLength - Given a pointer to an expanded or unexpanded argument, return the number of tokens...
Definition: MacroArgs.cpp:105
Encapsulates the data about a macro definition (e.g.
Definition: MacroInfo.h:34
static MacroArgs * create(const MacroInfo *MI, ArrayRef< Token > UnexpArgTokens, bool VarargsElided, Preprocessor &PP)
MacroArgs ctor function - Create a new MacroArgs object with the specified macro and argument info...
Definition: MacroArgs.cpp:25
Engages in a tight little dance with the lexer to efficiently preprocess tokens.
Definition: Preprocessor.h:98