1 //===--- UnnecessaryCopyInitialization.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_COPY_INITIALIZATION_H 10 #define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_UNNECESSARY_COPY_INITIALIZATION_H 11 12 #include "../ClangTidyCheck.h" 13 #include "clang/AST/Decl.h" 14 15 namespace clang { 16 namespace tidy { 17 namespace performance { 18 19 // The check detects local variable declarations that are copy initialized with 20 // the const reference of a function call or the const reference of a method 21 // call whose object is guaranteed to outlive the variable's scope and suggests 22 // to use a const reference. 23 // 24 // The check currently only understands a subset of variables that are 25 // guaranteed to outlive the const reference returned, namely: const variables, 26 // const references, and const pointers to const. 27 class UnnecessaryCopyInitialization : public ClangTidyCheck { 28 public: 29 UnnecessaryCopyInitialization(StringRef Name, ClangTidyContext *Context); isLanguageVersionSupported(const LangOptions & LangOpts)30 bool isLanguageVersionSupported(const LangOptions &LangOpts) const override{ 31 return LangOpts.CPlusPlus; 32 } 33 void registerMatchers(ast_matchers::MatchFinder *Finder) override; 34 void check(const ast_matchers::MatchFinder::MatchResult &Result) override; 35 void storeOptions(ClangTidyOptions::OptionMap &Opts) override; 36 37 private: 38 void handleCopyFromMethodReturn(const VarDecl &Var, const Stmt &BlockStmt, 39 const DeclStmt &Stmt, bool IssueFix, 40 const VarDecl *ObjectArg, 41 ASTContext &Context); 42 void handleCopyFromLocalVar(const VarDecl &NewVar, const VarDecl &OldVar, 43 const Stmt &BlockStmt, const DeclStmt &Stmt, 44 bool IssueFix, ASTContext &Context); 45 const std::vector<StringRef> AllowedTypes; 46 const std::vector<StringRef> ExcludedContainerTypes; 47 }; 48 49 } // namespace performance 50 } // namespace tidy 51 } // namespace clang 52 53 #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_UNNECESSARY_COPY_INITIALIZATION_H 54