clang  3.9.0
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(unsigned NumToks, bool varargsElided)
57  : NumUnexpArgTokens(NumToks), VarargsElided(varargsElided),
58  ArgCache(nullptr) {}
59  ~MacroArgs() = default;
60 
61 public:
62  /// MacroArgs ctor function - Create a new MacroArgs object with the specified
63  /// macro and argument info.
64  static MacroArgs *create(const MacroInfo *MI,
65  ArrayRef<Token> UnexpArgTokens,
66  bool VarargsElided, Preprocessor &PP);
67 
68  /// destroy - Destroy and deallocate the memory for this object.
69  ///
70  void destroy(Preprocessor &PP);
71 
72  /// ArgNeedsPreexpansion - If we can prove that the argument won't be affected
73  /// by pre-expansion, return false. Otherwise, conservatively return true.
74  bool ArgNeedsPreexpansion(const Token *ArgTok, Preprocessor &PP) const;
75 
76  /// getUnexpArgument - Return a pointer to the first token of the unexpanded
77  /// token list for the specified formal.
78  ///
79  const Token *getUnexpArgument(unsigned Arg) const;
80 
81  /// getArgLength - Given a pointer to an expanded or unexpanded argument,
82  /// return the number of tokens, not counting the EOF, that make up the
83  /// argument.
84  static unsigned getArgLength(const Token *ArgPtr);
85 
86  /// getPreExpArgument - Return the pre-expanded form of the specified
87  /// argument.
88  const std::vector<Token> &
89  getPreExpArgument(unsigned Arg, const MacroInfo *MI, Preprocessor &PP);
90 
91  /// getStringifiedArgument - Compute, cache, and return the specified argument
92  /// that has been 'stringified' as required by the # operator.
93  const Token &getStringifiedArgument(unsigned ArgNo, Preprocessor &PP,
94  SourceLocation ExpansionLocStart,
95  SourceLocation ExpansionLocEnd);
96 
97  /// getNumArguments - Return the number of arguments passed into this macro
98  /// invocation.
99  unsigned getNumArguments() const { return NumUnexpArgTokens; }
100 
101 
102  /// isVarargsElidedUse - Return true if this is a C99 style varargs macro
103  /// invocation and there was no argument specified for the "..." argument. If
104  /// the argument was specified (even empty) or this isn't a C99 style varargs
105  /// function, or if in strict mode and the C99 varargs macro had only a ...
106  /// argument, this returns false.
107  bool isVarargsElidedUse() const { return VarargsElided; }
108 
109  /// StringifyArgument - Implement C99 6.10.3.2p2, converting a sequence of
110  /// tokens into the literal string token that should be produced by the C #
111  /// preprocessor operator. If Charify is true, then it should be turned into
112  /// a character literal for the Microsoft charize (#@) extension.
113  ///
114  static Token StringifyArgument(const Token *ArgToks,
115  Preprocessor &PP, bool Charify,
116  SourceLocation ExpansionLocStart,
117  SourceLocation ExpansionLocEnd);
118 
119 
120  /// deallocate - This should only be called by the Preprocessor when managing
121  /// its freelist.
123 };
124 
125 } // end namespace clang
126 
127 #endif
bool isVarargsElidedUse() const
isVarargsElidedUse - Return true if this is a C99 style varargs macro invocation and there was no arg...
Definition: MacroArgs.h:107
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:147
void destroy(Preprocessor &PP)
destroy - Destroy and deallocate the memory for this object.
Definition: MacroArgs.cpp:73
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:113
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:297
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:194
MacroArgs - An instance of this class captures information about the formal arguments specified to a ...
Definition: MacroArgs.h:29
unsigned getNumArguments() const
getNumArguments - Return the number of arguments passed into this macro invocation.
Definition: MacroArgs.h:99
MacroArgs * deallocate()
deallocate - This should only be called by the Preprocessor when managing its freelist.
Definition: MacroArgs.cpp:88
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:131
static unsigned getArgLength(const Token *ArgPtr)
getArgLength - Given a pointer to an expanded or unexpanded argument, return the number of tokens...
Definition: MacroArgs.cpp:103
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:97