1 //===--- MacroArgs.h - Formal argument info for Macros ----------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the MacroArgs interface.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_CLANG_LEX_MACROARGS_H
15 #define LLVM_CLANG_LEX_MACROARGS_H
17 #include "clang/Basic/LLVM.h"
18 #include "clang/Lex/Token.h"
19 #include "llvm/ADT/ArrayRef.h"
20 #include "llvm/Support/TrailingObjects.h"
28 /// MacroArgs - An instance of this class captures information about
29 /// the formal arguments specified to a function-like macro invocation.
31 : private llvm::TrailingObjects<MacroArgs, Token> {
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;
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
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
50 std::vector<std::vector<Token> > PreExpArgTokens;
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;
56 /// ArgCache - This is a linked list of MacroArgs objects that the
57 /// Preprocessor owns which we use to avoid thrashing malloc/free.
60 /// MacroArgs - The number of arguments the invoked macro expects.
61 unsigned NumMacroArgs;
63 MacroArgs(unsigned NumToks, bool varargsElided, unsigned MacroArgs)
64 : NumUnexpArgTokens(NumToks), VarargsElided(varargsElided),
65 ArgCache(nullptr), NumMacroArgs(MacroArgs) {}
66 ~MacroArgs() = default;
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);
75 /// destroy - Destroy and deallocate the memory for this object.
77 void destroy(Preprocessor &PP);
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;
83 /// getUnexpArgument - Return a pointer to the first token of the unexpanded
84 /// token list for the specified formal.
86 const Token *getUnexpArgument(unsigned Arg) const;
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
91 static unsigned getArgLength(const Token *ArgPtr);
93 /// getPreExpArgument - Return the pre-expanded form of the specified
95 const std::vector<Token> &
96 getPreExpArgument(unsigned Arg, Preprocessor &PP);
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);
104 /// getNumMacroArguments - Return the number of arguments the invoked macro
106 unsigned getNumMacroArguments() const { return NumMacroArgs; }
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; }
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.
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.
127 bool invokedWithVariadicArgument(const MacroInfo *const MI) const;
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.
134 static Token StringifyArgument(const Token *ArgToks,
135 Preprocessor &PP, bool Charify,
136 SourceLocation ExpansionLocStart,
137 SourceLocation ExpansionLocEnd);
140 /// deallocate - This should only be called by the Preprocessor when managing
142 MacroArgs *deallocate();
145 } // end namespace clang