Imported Upstream version 6.10.0.49

Former-commit-id: 1d6753294b2993e1fbf92de9366bb9544db4189b

external/llvm-project/clang-tools-extra/clang-tidy/performance/ForRangeCopyCheck.h

@@ -0,0 +1,49 @@
+//===--- ForRangeCopyCheck.h - clang-tidy------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_FORRANGECOPYCHECK_H
+#define LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_FORRANGECOPYCHECK_H
+
+#include "../ClangTidy.h"
+
+namespace clang {
+namespace tidy {
+namespace performance {
+
+/// A check that detects copied loop variables and suggests using const
+/// references.
+/// For the user-facing documentation see:
+/// http://clang.llvm.org/extra/clang-tidy/checks/performance-for-range-copy.html
+class ForRangeCopyCheck : public ClangTidyCheck {
+public:
+  ForRangeCopyCheck(StringRef Name, ClangTidyContext *Context);
+  void storeOptions(ClangTidyOptions::OptionMap &Opts) override;
+  void registerMatchers(ast_matchers::MatchFinder *Finder) override;
+  void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+
+private:
+  // Checks if the loop variable is a const value and expensive to copy. If so
+  // suggests it be converted to a const reference.
+  bool handleConstValueCopy(const VarDecl &LoopVar, ASTContext &Context);
+
+  // Checks if the loop variable is a non-const value and whether only
+  // const methods are invoked on it or whether it is only used as a const
+  // reference argument. If so it suggests it be made a const reference.
+  bool handleCopyIsOnlyConstReferenced(const VarDecl &LoopVar,
+                                       const CXXForRangeStmt &ForRange,
+                                       ASTContext &Context);
+
+  const bool WarnOnAllAutoCopies;
+};
+
+} // namespace performance
+} // namespace tidy
+} // namespace clang
+
+#endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_PERFORMANCE_FORRANGECOPYCHECK_H