1 //===--- UnnecessaryValueParamCheck.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_UNNECESSARY_VALUE_PARAM_H 10 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_UNNECESSARY_VALUE_PARAM_H 11 12 #include "../ClangTidyCheck.h" 13 #include "../utils/IncludeInserter.h" 14 #include "clang/Analysis/Analyses/ExprMutationAnalyzer.h" 15 16 namespace clang::tidy::performance { 17 18 /// A check that flags value parameters of expensive to copy types that 19 /// can safely be converted to const references. 20 /// 21 /// For the user-facing documentation see: 22 /// http://clang.llvm.org/extra/clang-tidy/checks/performance/unnecessary-value-param.html 23 class UnnecessaryValueParamCheck : public ClangTidyCheck { 24 public: 25 UnnecessaryValueParamCheck(StringRef Name, ClangTidyContext *Context); 26 bool isLanguageVersionSupported(const LangOptions &LangOpts) const override { 27 return LangOpts.CPlusPlus; 28 } 29 void registerMatchers(ast_matchers::MatchFinder *Finder) override; 30 void check(const ast_matchers::MatchFinder::MatchResult &Result) override; 31 void registerPPCallbacks(const SourceManager &SM, Preprocessor *PP, 32 Preprocessor *ModuleExpanderPP) override; 33 void storeOptions(ClangTidyOptions::OptionMap &Opts) override; 34 void onEndOfTranslationUnit() override; 35 36 protected: 37 // Create diagnostics. These are virtual so that derived classes can change 38 // behaviour. 39 virtual void handleMoveFix(const ParmVarDecl &Param, 40 const DeclRefExpr &CopyArgument, 41 ASTContext &Context); 42 virtual void handleConstRefFix(const FunctionDecl &Function, 43 const ParmVarDecl &Param, ASTContext &Context); 44 45 private: 46 ExprMutationAnalyzer::Memoized MutationAnalyzerCache; 47 utils::IncludeInserter Inserter; 48 const std::vector<StringRef> AllowedTypes; 49 }; 50 51 } // namespace clang::tidy::performance 52 53 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_UNNECESSARY_VALUE_PARAM_H 54