clang-tools  6.0.0
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 IntegerTypesCheck::IntegerTypesCheck(StringRef Name, ClangTidyContext *Context)
44  : ClangTidyCheck(Name, Context),
45  UnsignedTypePrefix(Options.get("UnsignedTypePrefix", "uint")),
46  SignedTypePrefix(Options.get("SignedTypePrefix", "int")),
47  TypeSuffix(Options.get("TypeSuffix", "")) {}
48 
50  Options.store(Opts, "UnsignedTypePrefix", UnsignedTypePrefix);
51  Options.store(Opts, "SignedTypePrefix", SignedTypePrefix);
52  Options.store(Opts, "TypeSuffix", TypeSuffix);
53 }
54 
55 void IntegerTypesCheck::registerMatchers(MatchFinder *Finder) {
56  // Find all TypeLocs. The relevant Style Guide rule only applies to C++.
57  if (!getLangOpts().CPlusPlus)
58  return;
59  Finder->addMatcher(typeLoc(loc(isInteger())).bind("tl"), this);
60  IdentTable = llvm::make_unique<IdentifierTable>(getLangOpts());
61 }
62 
63 void IntegerTypesCheck::check(const MatchFinder::MatchResult &Result) {
64  auto TL = *Result.Nodes.getNodeAs<TypeLoc>("tl");
65  SourceLocation Loc = TL.getLocStart();
66 
67  if (Loc.isInvalid() || Loc.isMacroID())
68  return;
69 
70  // Look through qualification.
71  if (auto QualLoc = TL.getAs<QualifiedTypeLoc>())
72  TL = QualLoc.getUnqualifiedLoc();
73 
74  auto BuiltinLoc = TL.getAs<BuiltinTypeLoc>();
75  if (!BuiltinLoc)
76  return;
77 
78  Token Tok = getTokenAtLoc(Loc, Result, *IdentTable);
79  // Ensure the location actually points to one of the builting integral type
80  // names we're interested in. Otherwise, we might be getting this match from
81  // implicit code (e.g. an implicit assignment operator of a class containing
82  // an array of non-POD types).
83  if (!Tok.isOneOf(tok::kw_short, tok::kw_long, tok::kw_unsigned,
84  tok::kw_signed))
85  return;
86 
87  bool IsSigned;
88  unsigned Width;
89  const TargetInfo &TargetInfo = Result.Context->getTargetInfo();
90 
91  // Look for uses of short, long, long long and their unsigned versions.
92  switch (BuiltinLoc.getTypePtr()->getKind()) {
93  case BuiltinType::Short:
94  Width = TargetInfo.getShortWidth();
95  IsSigned = true;
96  break;
97  case BuiltinType::Long:
98  Width = TargetInfo.getLongWidth();
99  IsSigned = true;
100  break;
101  case BuiltinType::LongLong:
102  Width = TargetInfo.getLongLongWidth();
103  IsSigned = true;
104  break;
105  case BuiltinType::UShort:
106  Width = TargetInfo.getShortWidth();
107  IsSigned = false;
108  break;
109  case BuiltinType::ULong:
110  Width = TargetInfo.getLongWidth();
111  IsSigned = false;
112  break;
113  case BuiltinType::ULongLong:
114  Width = TargetInfo.getLongLongWidth();
115  IsSigned = false;
116  break;
117  default:
118  return;
119  }
120 
121  // We allow "unsigned short port" as that's reasonably common and required by
122  // the sockets API.
123  const StringRef Port = "unsigned short port";
124  const char *Data = Result.SourceManager->getCharacterData(Loc);
125  if (!std::strncmp(Data, Port.data(), Port.size()) &&
126  !isIdentifierBody(Data[Port.size()]))
127  return;
128 
129  std::string Replacement =
130  ((IsSigned ? SignedTypePrefix : UnsignedTypePrefix) + Twine(Width) +
131  TypeSuffix)
132  .str();
133 
134  // We don't add a fix-it as changing the type can easily break code,
135  // e.g. when a function requires a 'long' argument on all platforms.
136  // QualTypes are printed with implicit quotes.
137  diag(Loc, "consider replacing %0 with '%1'") << BuiltinLoc.getType()
138  << Replacement;
139 }
140 
141 } // namespace runtime
142 } // namespace google
143 } // namespace tidy
144 } // namespace clang
SourceLocation Loc
&#39;#&#39; location in the include directive
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:449
StringHandle Name
LangOptions getLangOpts() const
Returns the language options from the context.
Definition: ClangTidy.h:187
Base class for all clang-tidy checks.
Definition: ClangTidy.h:127
void registerMatchers(ast_matchers::MatchFinder *Finder) override
Override this to register AST matchers with Finder.
std::map< std::string, std::string > OptionMap
FunctionInfo Info
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&#39;s name.
Definition: ClangTidy.cpp:416