clang  6.0.0svn
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 "llvm/Support/TrailingObjects.h"
21 #include <vector>
22 
23 namespace clang {
24  class MacroInfo;
25  class Preprocessor;
26  class SourceLocation;
27 
28 /// MacroArgs - An instance of this class captures information about
29 /// the formal arguments specified to a function-like macro invocation.
30 class MacroArgs final
31  : private llvm::TrailingObjects<MacroArgs, Token> {
32 
33  friend TrailingObjects;
34  /// NumUnexpArgTokens - The number of raw, unexpanded tokens for the
35  /// arguments. All of the actual argument tokens are allocated immediately
36  /// after the MacroArgs object in memory. This is all of the arguments
37  /// concatenated together, with 'EOF' markers at the end of each argument.
38  unsigned NumUnexpArgTokens;
39 
40  /// VarargsElided - True if this is a C99 style varargs macro invocation and
41  /// there was no argument specified for the "..." argument. If the argument
42  /// was specified (even empty) or this isn't a C99 style varargs function, or
43  /// if in strict mode and the C99 varargs macro had only a ... argument, this
44  /// is false.
45  bool VarargsElided;
46 
47  /// PreExpArgTokens - Pre-expanded tokens for arguments that need them. Empty
48  /// if not yet computed. This includes the EOF marker at the end of the
49  /// stream.
50  std::vector<std::vector<Token> > PreExpArgTokens;
51 
52  /// StringifiedArgs - This contains arguments in 'stringified' form. If the
53  /// stringified form of an argument has not yet been computed, this is empty.
54  std::vector<Token> StringifiedArgs;
55 
56  /// ArgCache - This is a linked list of MacroArgs objects that the
57  /// Preprocessor owns which we use to avoid thrashing malloc/free.
58  MacroArgs *ArgCache;
59 
60  /// MacroArgs - The number of arguments the invoked macro expects.
61  unsigned NumMacroArgs;
62 
63  MacroArgs(unsigned NumToks, bool varargsElided, unsigned MacroArgs)
64  : NumUnexpArgTokens(NumToks), VarargsElided(varargsElided),
65  ArgCache(nullptr), NumMacroArgs(MacroArgs) {}
66  ~MacroArgs() = default;
67 
68 public:
69  /// MacroArgs ctor function - Create a new MacroArgs object with the specified
70  /// macro and argument info.
71  static MacroArgs *create(const MacroInfo *MI,
72  ArrayRef<Token> UnexpArgTokens,
73  bool VarargsElided, Preprocessor &PP);
74 
75  /// destroy - Destroy and deallocate the memory for this object.
76  ///
77  void destroy(Preprocessor &PP);
78 
79  /// ArgNeedsPreexpansion - If we can prove that the argument won't be affected
80  /// by pre-expansion, return false. Otherwise, conservatively return true.
81  bool ArgNeedsPreexpansion(const Token *ArgTok, Preprocessor &PP) const;
82 
83  /// getUnexpArgument - Return a pointer to the first token of the unexpanded
84  /// token list for the specified formal.
85  ///
86  const Token *getUnexpArgument(unsigned Arg) const;
87 
88  /// getArgLength - Given a pointer to an expanded or unexpanded argument,
89  /// return the number of tokens, not counting the EOF, that make up the
90  /// argument.
91  static unsigned getArgLength(const Token *ArgPtr);
92 
93  /// getPreExpArgument - Return the pre-expanded form of the specified
94  /// argument.
95  const std::vector<Token> &
96  getPreExpArgument(unsigned Arg, Preprocessor &PP);
97 
98  /// getStringifiedArgument - Compute, cache, and return the specified argument
99  /// that has been 'stringified' as required by the # operator.
100  const Token &getStringifiedArgument(unsigned ArgNo, Preprocessor &PP,
101  SourceLocation ExpansionLocStart,
102  SourceLocation ExpansionLocEnd);
103 
104  /// getNumMacroArguments - Return the number of arguments the invoked macro
105  /// expects.
106  unsigned getNumMacroArguments() const { return NumMacroArgs; }
107 
108  /// isVarargsElidedUse - Return true if this is a C99 style varargs macro
109  /// invocation and there was no argument specified for the "..." argument. If
110  /// the argument was specified (even empty) or this isn't a C99 style varargs
111  /// function, or if in strict mode and the C99 varargs macro had only a ...
112  /// argument, this returns false.
113  bool isVarargsElidedUse() const { return VarargsElided; }
114 
115  /// Returns true if the macro was defined with a variadic (ellipsis) parameter
116  /// AND was invoked with at least one token supplied as a variadic argument.
117  ///
118  /// \code
119  /// #define F(a) a
120  /// #define V(a, ...) __VA_OPT__(a)
121  /// F() <-- returns false on this invocation.
122  /// V(,a) <-- returns true on this invocation.
123  /// V(,) <-- returns false on this invocation.
124  /// \endcode
125  ///
126 
127  bool invokedWithVariadicArgument(const MacroInfo *const MI) const;
128 
129  /// StringifyArgument - Implement C99 6.10.3.2p2, converting a sequence of
130  /// tokens into the literal string token that should be produced by the C #
131  /// preprocessor operator. If Charify is true, then it should be turned into
132  /// a character literal for the Microsoft charize (#@) extension.
133  ///
134  static Token StringifyArgument(const Token *ArgToks,
135  Preprocessor &PP, bool Charify,
136  SourceLocation ExpansionLocStart,
137  SourceLocation ExpansionLocEnd);
138 
139 
140  /// deallocate - This should only be called by the Preprocessor when managing
141  /// its freelist.
142  MacroArgs *deallocate();
143 };
144 
145 } // end namespace clang
146 
147 #endif
bool invokedWithVariadicArgument(const MacroInfo *const MI) const
Returns true if the macro was defined with a variadic (ellipsis) parameter AND was invoked with at le...
Definition: MacroArgs.cpp:142
bool ArgNeedsPreexpansion(const Token *ArgTok, Preprocessor &PP) const
ArgNeedsPreexpansion - If we can prove that the argument won&#39;t be affected by pre-expansion, return false.
Definition: MacroArgs.cpp:151
bool isVarargsElidedUse() const
isVarargsElidedUse - Return true if this is a C99 style varargs macro invocation and there was no arg...
Definition: MacroArgs.h:113
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...
void destroy(Preprocessor &PP)
destroy - Destroy and deallocate the memory for this object.
Definition: MacroArgs.cpp:78
const Token & getStringifiedArgument(unsigned ArgNo, Preprocessor &PP, SourceLocation ExpansionLocStart, SourceLocation ExpansionLocEnd)
getStringifiedArgument - Compute, cache, and return the specified argument that has been &#39;stringified...
Definition: MacroArgs.cpp:316
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:213
MacroArgs - An instance of this class captures information about the formal arguments specified to a ...
Definition: MacroArgs.h:30
MacroArgs * deallocate()
deallocate - This should only be called by the Preprocessor when managing its freelist.
Definition: MacroArgs.cpp:93
Encodes a location in the source.
Dataflow Directional Tag Classes.
const std::vector< Token > & getPreExpArgument(unsigned Arg, Preprocessor &PP)
getPreExpArgument - Return the pre-expanded form of the specified argument.
Definition: MacroArgs.cpp:166
static unsigned getArgLength(const Token *ArgPtr)
getArgLength - Given a pointer to an expanded or unexpanded argument, return the number of tokens...
Definition: MacroArgs.cpp:110
unsigned getNumMacroArguments() const
getNumMacroArguments - Return the number of arguments the invoked macro expects.
Definition: MacroArgs.h:106
Encapsulates the data about a macro definition (e.g.
Definition: MacroInfo.h:40
friend TrailingObjects
Definition: OpenMPClause.h:84
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
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:120
Engages in a tight little dance with the lexer to efficiently preprocess tokens.
Definition: Preprocessor.h:127