clang-tools-extra/clang-tidy/performance/ForRangeCopyCheck.h

   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);
  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