clang-tools  3.9.0
IntegerTypesCheck.cpp
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1 //===--- IntegerTypesCheck.cpp - clang-tidy -------------------------------===//
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 #include "IntegerTypesCheck.h"
11 #include "clang/AST/ASTContext.h"
12 #include "clang/ASTMatchers/ASTMatchFinder.h"
13 #include "clang/ASTMatchers/ASTMatchers.h"
14 #include "clang/Basic/CharInfo.h"
15 #include "clang/Basic/IdentifierTable.h"
16 #include "clang/Basic/TargetInfo.h"
17 #include "clang/Lex/Lexer.h"
18 
19 namespace clang {
20 
21 using namespace ast_matchers;
22 
23 static Token getTokenAtLoc(SourceLocation Loc,
24  const MatchFinder::MatchResult &MatchResult,
25  IdentifierTable &IdentTable) {
26  Token Tok;
27  if (Lexer::getRawToken(Loc, Tok, *MatchResult.SourceManager,
28  MatchResult.Context->getLangOpts(), false))
29  return Tok;
30 
31  if (Tok.is(tok::raw_identifier)) {
32  IdentifierInfo &Info = IdentTable.get(Tok.getRawIdentifier());
33  Tok.setIdentifierInfo(&Info);
34  Tok.setKind(Info.getTokenID());
35  }
36  return Tok;
37 }
38 
39 namespace tidy {
40 namespace google {
41 namespace runtime {
42 
43 
44 IntegerTypesCheck::IntegerTypesCheck(StringRef Name, ClangTidyContext *Context)
45  : ClangTidyCheck(Name, Context),
46  UnsignedTypePrefix(Options.get("UnsignedTypePrefix", "uint")),
47  SignedTypePrefix(Options.get("SignedTypePrefix", "int")),
48  TypeSuffix(Options.get("TypeSuffix", "")) {}
49 
51  Options.store(Opts, "UnsignedTypePrefix", UnsignedTypePrefix);
52  Options.store(Opts, "SignedTypePrefix", SignedTypePrefix);
53  Options.store(Opts, "TypeSuffix", TypeSuffix);
54 }
55 
57  // Find all TypeLocs. The relevant Style Guide rule only applies to C++.
58  if (!getLangOpts().CPlusPlus)
59  return;
60  Finder->addMatcher(typeLoc(loc(isInteger())).bind("tl"), this);
61  IdentTable = llvm::make_unique<IdentifierTable>(getLangOpts());
62 }
63 
64 void IntegerTypesCheck::check(const MatchFinder::MatchResult &Result) {
65  auto TL = *Result.Nodes.getNodeAs<TypeLoc>("tl");
66  SourceLocation Loc = TL.getLocStart();
67 
68  if (Loc.isInvalid() || Loc.isMacroID())
69  return;
70 
71  // Look through qualification.
72  if (auto QualLoc = TL.getAs<QualifiedTypeLoc>())
73  TL = QualLoc.getUnqualifiedLoc();
74 
75  auto BuiltinLoc = TL.getAs<BuiltinTypeLoc>();
76  if (!BuiltinLoc)
77  return;
78 
79  Token Tok = getTokenAtLoc(Loc, Result, *IdentTable);
80  // Ensure the location actually points to one of the builting integral type
81  // names we're interested in. Otherwise, we might be getting this match from
82  // implicit code (e.g. an implicit assignment operator of a class containing
83  // an array of non-POD types).
84  if (!Tok.isOneOf(tok::kw_short, tok::kw_long, tok::kw_unsigned,
85  tok::kw_signed))
86  return;
87 
88  bool IsSigned;
89  unsigned Width;
90  const TargetInfo &TargetInfo = Result.Context->getTargetInfo();
91 
92  // Look for uses of short, long, long long and their unsigned versions.
93  switch (BuiltinLoc.getTypePtr()->getKind()) {
94  case BuiltinType::Short:
95  Width = TargetInfo.getShortWidth();
96  IsSigned = true;
97  break;
98  case BuiltinType::Long:
99  Width = TargetInfo.getLongWidth();
100  IsSigned = true;
101  break;
102  case BuiltinType::LongLong:
103  Width = TargetInfo.getLongLongWidth();
104  IsSigned = true;
105  break;
106  case BuiltinType::UShort:
107  Width = TargetInfo.getShortWidth();
108  IsSigned = false;
109  break;
110  case BuiltinType::ULong:
111  Width = TargetInfo.getLongWidth();
112  IsSigned = false;
113  break;
114  case BuiltinType::ULongLong:
115  Width = TargetInfo.getLongLongWidth();
116  IsSigned = false;
117  break;
118  default:
119  return;
120  }
121 
122  // We allow "unsigned short port" as that's reasonably common and required by
123  // the sockets API.
124  const StringRef Port = "unsigned short port";
125  const char *Data = Result.SourceManager->getCharacterData(Loc);
126  if (!std::strncmp(Data, Port.data(), Port.size()) &&
127  !isIdentifierBody(Data[Port.size()]))
128  return;
129 
130  std::string Replacement =
131  ((IsSigned ? SignedTypePrefix : UnsignedTypePrefix) + Twine(Width) +
132  TypeSuffix)
133  .str();
134 
135  // We don't add a fix-it as changing the type can easily break code,
136  // e.g. when a function requires a 'long' argument on all platforms.
137  // QualTypes are printed with implicit quotes.
138  diag(Loc, "consider replacing %0 with '%1'") << BuiltinLoc.getType()
139  << Replacement;
140 }
141 
142 } // namespace runtime
143 } // namespace google
144 } // namespace tidy
145 } // namespace clang
SourceLocation Loc
'#' location in the include directive
const std::string Name
Definition: USRFinder.cpp:140
LangOptions getLangOpts() const
Returns the language options from the context.
Definition: ClangTidy.h:170
std::unique_ptr< ast_matchers::MatchFinder > Finder
Definition: ClangTidy.cpp:210
Base class for all clang-tidy checks.
Definition: ClangTidy.h:110
void registerMatchers(ast_matchers::MatchFinder *Finder) override
Override this to register AST matchers with Finder.
void store(ClangTidyOptions::OptionMap &Options, StringRef LocalName, StringRef Value) const
Stores an option with the check-local name LocalName with string value Value to Options.
Definition: ClangTidy.cpp:385
std::map< std::string, std::string > OptionMap
ClangTidyContext & Context
Definition: ClangTidy.cpp:93
Every ClangTidyCheck reports errors through a DiagnosticsEngine provided by this context.
void check(const ast_matchers::MatchFinder::MatchResult &Result) override
ClangTidyChecks that register ASTMatchers should do the actual work in here.
void storeOptions(ClangTidyOptions::OptionMap &Options) override
Should store all options supported by this check with their current values or default values for opti...
static Token getTokenAtLoc(SourceLocation Loc, const MatchFinder::MatchResult &MatchResult, IdentifierTable &IdentTable)
DiagnosticBuilder diag(SourceLocation Loc, StringRef Description, DiagnosticIDs::Level Level=DiagnosticIDs::Warning)
Add a diagnostic with the check's name.
Definition: ClangTidy.cpp:352
const NamedDecl * Result
Definition: USRFinder.cpp:137