1 //===--- MacroInfo.cpp - Information about #defined identifiers -----------===//
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 implements the MacroInfo interface.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "clang/Lex/MacroInfo.h"
15 #include "clang/Lex/Preprocessor.h"
16 using namespace clang;
17
MacroInfo(SourceLocation DefLoc)18 MacroInfo::MacroInfo(SourceLocation DefLoc)
19 : Location(DefLoc),
20 ArgumentList(nullptr),
21 NumArguments(0),
22 IsDefinitionLengthCached(false),
23 IsFunctionLike(false),
24 IsC99Varargs(false),
25 IsGNUVarargs(false),
26 IsBuiltinMacro(false),
27 HasCommaPasting(false),
28 IsDisabled(false),
29 IsUsed(false),
30 IsAllowRedefinitionsWithoutWarning(false),
31 IsWarnIfUnused(false),
32 FromASTFile(false),
33 UsedForHeaderGuard(false) {
34 }
35
getDefinitionLengthSlow(SourceManager & SM) const36 unsigned MacroInfo::getDefinitionLengthSlow(SourceManager &SM) const {
37 assert(!IsDefinitionLengthCached);
38 IsDefinitionLengthCached = true;
39
40 if (ReplacementTokens.empty())
41 return (DefinitionLength = 0);
42
43 const Token &firstToken = ReplacementTokens.front();
44 const Token &lastToken = ReplacementTokens.back();
45 SourceLocation macroStart = firstToken.getLocation();
46 SourceLocation macroEnd = lastToken.getLocation();
47 assert(macroStart.isValid() && macroEnd.isValid());
48 assert((macroStart.isFileID() || firstToken.is(tok::comment)) &&
49 "Macro defined in macro?");
50 assert((macroEnd.isFileID() || lastToken.is(tok::comment)) &&
51 "Macro defined in macro?");
52 std::pair<FileID, unsigned>
53 startInfo = SM.getDecomposedExpansionLoc(macroStart);
54 std::pair<FileID, unsigned>
55 endInfo = SM.getDecomposedExpansionLoc(macroEnd);
56 assert(startInfo.first == endInfo.first &&
57 "Macro definition spanning multiple FileIDs ?");
58 assert(startInfo.second <= endInfo.second);
59 DefinitionLength = endInfo.second - startInfo.second;
60 DefinitionLength += lastToken.getLength();
61
62 return DefinitionLength;
63 }
64
65 /// \brief Return true if the specified macro definition is equal to
66 /// this macro in spelling, arguments, and whitespace.
67 ///
68 /// \param Syntactically if true, the macro definitions can be identical even
69 /// if they use different identifiers for the function macro parameters.
70 /// Otherwise the comparison is lexical and this implements the rules in
71 /// C99 6.10.3.
isIdenticalTo(const MacroInfo & Other,Preprocessor & PP,bool Syntactically) const72 bool MacroInfo::isIdenticalTo(const MacroInfo &Other, Preprocessor &PP,
73 bool Syntactically) const {
74 bool Lexically = !Syntactically;
75
76 // Check # tokens in replacement, number of args, and various flags all match.
77 if (ReplacementTokens.size() != Other.ReplacementTokens.size() ||
78 getNumArgs() != Other.getNumArgs() ||
79 isFunctionLike() != Other.isFunctionLike() ||
80 isC99Varargs() != Other.isC99Varargs() ||
81 isGNUVarargs() != Other.isGNUVarargs())
82 return false;
83
84 if (Lexically) {
85 // Check arguments.
86 for (arg_iterator I = arg_begin(), OI = Other.arg_begin(), E = arg_end();
87 I != E; ++I, ++OI)
88 if (*I != *OI) return false;
89 }
90
91 // Check all the tokens.
92 for (unsigned i = 0, e = ReplacementTokens.size(); i != e; ++i) {
93 const Token &A = ReplacementTokens[i];
94 const Token &B = Other.ReplacementTokens[i];
95 if (A.getKind() != B.getKind())
96 return false;
97
98 // If this isn't the first first token, check that the whitespace and
99 // start-of-line characteristics match.
100 if (i != 0 &&
101 (A.isAtStartOfLine() != B.isAtStartOfLine() ||
102 A.hasLeadingSpace() != B.hasLeadingSpace()))
103 return false;
104
105 // If this is an identifier, it is easy.
106 if (A.getIdentifierInfo() || B.getIdentifierInfo()) {
107 if (A.getIdentifierInfo() == B.getIdentifierInfo())
108 continue;
109 if (Lexically)
110 return false;
111 // With syntactic equivalence the parameter names can be different as long
112 // as they are used in the same place.
113 int AArgNum = getArgumentNum(A.getIdentifierInfo());
114 if (AArgNum == -1)
115 return false;
116 if (AArgNum != Other.getArgumentNum(B.getIdentifierInfo()))
117 return false;
118 continue;
119 }
120
121 // Otherwise, check the spelling.
122 if (PP.getSpelling(A) != PP.getSpelling(B))
123 return false;
124 }
125
126 return true;
127 }
128
getDefinition()129 MacroDirective::DefInfo MacroDirective::getDefinition() {
130 MacroDirective *MD = this;
131 SourceLocation UndefLoc;
132 Optional<bool> isPublic;
133 for (; MD; MD = MD->getPrevious()) {
134 if (DefMacroDirective *DefMD = dyn_cast<DefMacroDirective>(MD))
135 return DefInfo(DefMD, UndefLoc,
136 !isPublic.hasValue() || isPublic.getValue());
137
138 if (UndefMacroDirective *UndefMD = dyn_cast<UndefMacroDirective>(MD)) {
139 UndefLoc = UndefMD->getLocation();
140 continue;
141 }
142
143 VisibilityMacroDirective *VisMD = cast<VisibilityMacroDirective>(MD);
144 if (!isPublic.hasValue())
145 isPublic = VisMD->isPublic();
146 }
147
148 return DefInfo(nullptr, UndefLoc,
149 !isPublic.hasValue() || isPublic.getValue());
150 }
151
152 const MacroDirective::DefInfo
findDirectiveAtLoc(SourceLocation L,SourceManager & SM) const153 MacroDirective::findDirectiveAtLoc(SourceLocation L, SourceManager &SM) const {
154 assert(L.isValid() && "SourceLocation is invalid.");
155 for (DefInfo Def = getDefinition(); Def; Def = Def.getPreviousDefinition()) {
156 if (Def.getLocation().isInvalid() || // For macros defined on the command line.
157 SM.isBeforeInTranslationUnit(Def.getLocation(), L))
158 return (!Def.isUndefined() ||
159 SM.isBeforeInTranslationUnit(L, Def.getUndefLocation()))
160 ? Def : DefInfo();
161 }
162 return DefInfo();
163 }
164