xref: /llvm-project/clang-tools-extra/clang-tidy/performance/ForRangeCopyCheck.h (revision 4718da506091a37ca4863d979bc541e359b79b10)
1 //===--- ForRangeCopyCheck.h - clang-tidy------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_FORRANGECOPYCHECK_H
10 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_FORRANGECOPYCHECK_H
11 
12 #include "../ClangTidyCheck.h"
13 
14 namespace clang::tidy::performance {
15 
16 /// A check that detects copied loop variables and suggests using const
17 /// references.
18 /// For the user-facing documentation see:
19 /// http://clang.llvm.org/extra/clang-tidy/checks/performance/for-range-copy.html
20 class ForRangeCopyCheck : public ClangTidyCheck {
21 public:
22   ForRangeCopyCheck(StringRef Name, ClangTidyContext *Context);
isLanguageVersionSupported(const LangOptions & LangOpts)23   bool isLanguageVersionSupported(const LangOptions &LangOpts) const override{
24     return LangOpts.CPlusPlus11;
25   }
26   void storeOptions(ClangTidyOptions::OptionMap &Opts) override;
27   void registerMatchers(ast_matchers::MatchFinder *Finder) override;
28   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
29 
30 private:
31   // Checks if the loop variable is a const value and expensive to copy. If so
32   // suggests it be converted to a const reference.
33   bool handleConstValueCopy(const VarDecl &LoopVar, ASTContext &Context);
34 
35   // Checks if the loop variable is a non-const value and whether only
36   // const methods are invoked on it or whether it is only used as a const
37   // reference argument. If so it suggests it be made a const reference.
38   bool handleCopyIsOnlyConstReferenced(const VarDecl &LoopVar,
39                                        const CXXForRangeStmt &ForRange,
40                                        ASTContext &Context);
41 
42   const bool WarnOnAllAutoCopies;
43   const std::vector<StringRef> AllowedTypes;
44 };
45 
46 } // namespace clang::tidy::performance
47 
48 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_FORRANGECOPYCHECK_H
49