1 //=======- PtrTypesSemantics.cpp ---------------------------------*- 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_ANALYZER_WEBKIT_PTRTYPESEMANTICS_H 10 #define LLVM_CLANG_ANALYZER_WEBKIT_PTRTYPESEMANTICS_H 11 12 #include "llvm/ADT/APInt.h" 13 #include "llvm/ADT/DenseMap.h" 14 #include "llvm/ADT/PointerUnion.h" 15 #include <optional> 16 17 namespace clang { 18 class CXXBaseSpecifier; 19 class CXXMethodDecl; 20 class CXXRecordDecl; 21 class Decl; 22 class FunctionDecl; 23 class QualType; 24 class Stmt; 25 class Type; 26 27 // Ref-countability of a type is implicitly defined by Ref<T> and RefPtr<T> 28 // implementation. It can be modeled as: type T having public methods ref() and 29 // deref() 30 31 // In WebKit there are two ref-counted templated smart pointers: RefPtr<T> and 32 // Ref<T>. 33 34 /// \returns CXXRecordDecl of the base if the type has ref as a public method, 35 /// nullptr if not, std::nullopt if inconclusive. 36 std::optional<const clang::CXXRecordDecl *> 37 hasPublicMethodInBase(const CXXBaseSpecifier *Base, 38 llvm::StringRef NameToMatch); 39 40 /// \returns true if \p Class is ref-countable, false if not, std::nullopt if 41 /// inconclusive. 42 std::optional<bool> isRefCountable(const clang::CXXRecordDecl *Class); 43 44 /// \returns true if \p Class is checked-pointer compatible, false if not, 45 /// std::nullopt if inconclusive. 46 std::optional<bool> isCheckedPtrCapable(const clang::CXXRecordDecl *Class); 47 48 /// \returns true if \p Class is ref-counted, false if not. 49 bool isRefCounted(const clang::CXXRecordDecl *Class); 50 51 /// \returns true if \p Class is a CheckedPtr / CheckedRef, false if not. 52 bool isCheckedPtr(const clang::CXXRecordDecl *Class); 53 54 /// \returns true if \p Class is ref-countable AND not ref-counted, false if 55 /// not, std::nullopt if inconclusive. 56 std::optional<bool> isUncounted(const clang::QualType T); 57 58 /// \returns true if \p Class is CheckedPtr capable AND not checked, false if 59 /// not, std::nullopt if inconclusive. 60 std::optional<bool> isUnchecked(const clang::QualType T); 61 62 /// \returns true if \p Class is ref-countable AND not ref-counted, false if 63 /// not, std::nullopt if inconclusive. 64 std::optional<bool> isUncounted(const clang::CXXRecordDecl* Class); 65 66 /// \returns true if \p Class is CheckedPtr capable AND not checked, false if 67 /// not, std::nullopt if inconclusive. 68 std::optional<bool> isUnchecked(const clang::CXXRecordDecl *Class); 69 70 /// \returns true if \p T is either a raw pointer or reference to an uncounted 71 /// class, false if not, std::nullopt if inconclusive. 72 std::optional<bool> isUncountedPtr(const clang::QualType T); 73 74 /// \returns true if \p T is either a raw pointer or reference to an unchecked 75 /// class, false if not, std::nullopt if inconclusive. 76 std::optional<bool> isUncheckedPtr(const clang::QualType T); 77 78 /// \returns true if \p T is either a raw pointer or reference to an uncounted 79 /// or unchecked class, false if not, std::nullopt if inconclusive. 80 std::optional<bool> isUnsafePtr(const QualType T); 81 82 /// \returns true if \p T is a RefPtr, Ref, CheckedPtr, CheckedRef, or its 83 /// variant, false if not. 84 bool isSafePtrType(const clang::QualType T); 85 86 /// \returns true if \p T is a RefPtr, Ref, CheckedPtr, CheckedRef, or 87 /// unique_ptr, false if not. 88 bool isOwnerPtrType(const clang::QualType T); 89 90 /// \returns true if \p F creates ref-countable object from uncounted parameter, 91 /// false if not. 92 bool isCtorOfRefCounted(const clang::FunctionDecl *F); 93 94 /// \returns true if \p F creates checked ptr object from uncounted parameter, 95 /// false if not. 96 bool isCtorOfCheckedPtr(const clang::FunctionDecl *F); 97 98 /// \returns true if \p F creates ref-countable or checked ptr object from 99 /// uncounted parameter, false if not. 100 bool isCtorOfSafePtr(const clang::FunctionDecl *F); 101 102 /// \returns true if \p Name is RefPtr, Ref, or its variant, false if not. 103 bool isRefType(const std::string &Name); 104 105 /// \returns true if \p Name is CheckedRef or CheckedPtr, false if not. 106 bool isCheckedPtr(const std::string &Name); 107 108 /// \returns true if \p M is getter of a ref-counted class, false if not. 109 std::optional<bool> isGetterOfSafePtr(const clang::CXXMethodDecl *Method); 110 111 /// \returns true if \p F is a conversion between ref-countable or ref-counted 112 /// pointer types. 113 bool isPtrConversion(const FunctionDecl *F); 114 115 /// \returns true if \p F is a static singleton function. 116 bool isSingleton(const FunctionDecl *F); 117 118 /// An inter-procedural analysis facility that detects functions with "trivial" 119 /// behavior with respect to reference counting, such as simple field getters. 120 class TrivialFunctionAnalysis { 121 public: 122 /// \returns true if \p D is a "trivial" function. 123 bool isTrivial(const Decl *D) const { return isTrivialImpl(D, TheCache); } 124 bool isTrivial(const Stmt *S) const { return isTrivialImpl(S, TheCache); } 125 126 private: 127 friend class TrivialFunctionAnalysisVisitor; 128 129 using CacheTy = 130 llvm::DenseMap<llvm::PointerUnion<const Decl *, const Stmt *>, bool>; 131 mutable CacheTy TheCache{}; 132 133 static bool isTrivialImpl(const Decl *D, CacheTy &Cache); 134 static bool isTrivialImpl(const Stmt *S, CacheTy &Cache); 135 }; 136 137 } // namespace clang 138 139 #endif 140