| 1 | //===--- IdDependentBackwardBranchCheck.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_ALTERA_IDDEPENDENTBACKWARDBRANCHCHECK_H |
| 10 | #define |
| 11 | |
| 12 | #include "../ClangTidyCheck.h" |
| 13 | |
| 14 | namespace clang::tidy::altera { |
| 15 | |
| 16 | /// Finds ID-dependent variables and fields used within loops, and warns of |
| 17 | /// their usage. Using these variables in loops can lead to performance |
| 18 | /// degradation. |
| 19 | /// |
| 20 | /// For the user-facing documentation see: |
| 21 | /// http://clang.llvm.org/extra/clang-tidy/checks/altera/id-dependent-backward-branch.html |
| 22 | class IdDependentBackwardBranchCheck : public ClangTidyCheck { |
| 23 | private: |
| 24 | enum LoopType { UnknownLoop = -1, DoLoop = 0, WhileLoop = 1, ForLoop = 2 }; |
| 25 | // Stores information necessary for printing out source of error. |
| 26 | struct IdDependencyRecord { |
| 27 | IdDependencyRecord(const VarDecl *Declaration, SourceLocation Location, |
| 28 | const llvm::Twine &Message) |
| 29 | : VariableDeclaration(Declaration), Location(Location), |
| 30 | Message(Message.str()) {} |
| 31 | IdDependencyRecord(const FieldDecl *Declaration, SourceLocation Location, |
| 32 | const llvm::Twine &Message) |
| 33 | : FieldDeclaration(Declaration), Location(Location), |
| 34 | Message(Message.str()) {} |
| 35 | IdDependencyRecord() = default; |
| 36 | const VarDecl *VariableDeclaration = nullptr; |
| 37 | const FieldDecl *FieldDeclaration = nullptr; |
| 38 | SourceLocation Location; |
| 39 | std::string Message; |
| 40 | }; |
| 41 | // Stores the locations where ID-dependent variables are created. |
| 42 | std::map<const VarDecl *, IdDependencyRecord> IdDepVarsMap; |
| 43 | // Stores the locations where ID-dependent fields are created. |
| 44 | std::map<const FieldDecl *, IdDependencyRecord> IdDepFieldsMap; |
| 45 | /// Returns an IdDependencyRecord if the Expression contains an ID-dependent |
| 46 | /// variable, returns a nullptr otherwise. |
| 47 | IdDependencyRecord *hasIdDepVar(const Expr *Expression); |
| 48 | /// Returns an IdDependencyRecord if the Expression contains an ID-dependent |
| 49 | /// field, returns a nullptr otherwise. |
| 50 | IdDependencyRecord *hasIdDepField(const Expr *Expression); |
| 51 | /// Stores the location an ID-dependent variable is created from a call to |
| 52 | /// an ID function in IdDepVarsMap. |
| 53 | void saveIdDepVar(const Stmt *Statement, const VarDecl *Variable); |
| 54 | /// Stores the location an ID-dependent field is created from a call to an ID |
| 55 | /// function in IdDepFieldsMap. |
| 56 | void saveIdDepField(const Stmt *Statement, const FieldDecl *Field); |
| 57 | /// Stores the location an ID-dependent variable is created from a reference |
| 58 | /// to another ID-dependent variable or field in IdDepVarsMap. |
| 59 | void saveIdDepVarFromReference(const DeclRefExpr *RefExpr, |
| 60 | const MemberExpr *MemExpr, |
| 61 | const VarDecl *PotentialVar); |
| 62 | /// Stores the location an ID-dependent field is created from a reference to |
| 63 | /// another ID-dependent variable or field in IdDepFieldsMap. |
| 64 | void saveIdDepFieldFromReference(const DeclRefExpr *RefExpr, |
| 65 | const MemberExpr *MemExpr, |
| 66 | const FieldDecl *PotentialField); |
| 67 | /// Returns the loop type. |
| 68 | LoopType getLoopType(const Stmt *Loop); |
| 69 | |
| 70 | public: |
| 71 | IdDependentBackwardBranchCheck(StringRef Name, ClangTidyContext *Context) |
| 72 | : ClangTidyCheck(Name, Context) {} |
| 73 | void registerMatchers(ast_matchers::MatchFinder *Finder) override; |
| 74 | void check(const ast_matchers::MatchFinder::MatchResult &Result) override; |
| 75 | }; |
| 76 | |
| 77 | } // namespace clang::tidy::altera |
| 78 | |
| 79 | #endif // LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_ALTERA_IDDEPENDENTBACKWARDBRANCHCHECK_H |
| 80 | |