1//===---- CheckerHelpers.cpp - Helper functions for checkers ----*- 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// This file defines several static functions for use in checkers.
10//
11//===----------------------------------------------------------------------===//
12
13#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerHelpers.h"
14#include "clang/AST/Decl.h"
15#include "clang/AST/Expr.h"
16#include "clang/Lex/Preprocessor.h"
17
18namespace clang {
19
20namespace ento {
21
22// Recursively find any substatements containing macros
23bool containsMacro(const Stmt *S) {
24 if (S->getBeginLoc().isMacroID())
25 return true;
26
27 if (S->getEndLoc().isMacroID())
28 return true;
29
30 for (const Stmt *Child : S->children())
31 if (Child && containsMacro(Child))
32 return true;
33
34 return false;
35}
36
37// Recursively find any substatements containing enum constants
38bool containsEnum(const Stmt *S) {
39 const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(S);
40
41 if (DR && isa<EnumConstantDecl>(DR->getDecl()))
42 return true;
43
44 for (const Stmt *Child : S->children())
45 if (Child && containsEnum(Child))
46 return true;
47
48 return false;
49}
50
51// Recursively find any substatements containing static vars
52bool containsStaticLocal(const Stmt *S) {
53 const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(S);
54
55 if (DR)
56 if (const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl()))
57 if (VD->isStaticLocal())
58 return true;
59
60 for (const Stmt *Child : S->children())
61 if (Child && containsStaticLocal(Child))
62 return true;
63
64 return false;
65}
66
67// Recursively find any substatements containing __builtin_offsetof
68bool containsBuiltinOffsetOf(const Stmt *S) {
69 if (isa<OffsetOfExpr>(S))
70 return true;
71
72 for (const Stmt *Child : S->children())
73 if (Child && containsBuiltinOffsetOf(Child))
74 return true;
75
76 return false;
77}
78
79// Extract lhs and rhs from assignment statement
80std::pair<const clang::VarDecl *, const clang::Expr *>
81parseAssignment(const Stmt *S) {
82 const VarDecl *VD = nullptr;
83 const Expr *RHS = nullptr;
84
85 if (auto Assign = dyn_cast_or_null<BinaryOperator>(S)) {
86 if (Assign->isAssignmentOp()) {
87 // Ordinary assignment
88 RHS = Assign->getRHS();
89 if (auto DE = dyn_cast_or_null<DeclRefExpr>(Assign->getLHS()))
90 VD = dyn_cast_or_null<VarDecl>(DE->getDecl());
91 }
92 } else if (auto PD = dyn_cast_or_null<DeclStmt>(S)) {
93 // Initialization
94 assert(PD->isSingleDecl() && "We process decls one by one");
95 VD = cast<VarDecl>(PD->getSingleDecl());
96 RHS = VD->getAnyInitializer();
97 }
98
99 return std::make_pair(VD, RHS);
100}
101
102Nullability getNullabilityAnnotation(QualType Type) {
103 const auto *AttrType = Type->getAs<AttributedType>();
104 if (!AttrType)
105 return Nullability::Unspecified;
106 if (AttrType->getAttrKind() == attr::TypeNullable)
107 return Nullability::Nullable;
108 else if (AttrType->getAttrKind() == attr::TypeNonNull)
109 return Nullability::Nonnull;
110 return Nullability::Unspecified;
111}
112
113llvm::Optional<int> tryExpandAsInteger(StringRef Macro,
114 const Preprocessor &PP) {
115 const auto *MacroII = PP.getIdentifierInfo(Macro);
116 if (!MacroII)
117 return llvm::None;
118 const MacroInfo *MI = PP.getMacroInfo(MacroII);
119 if (!MI)
120 return llvm::None;
121
122 // Filter out parens.
123 std::vector<Token> FilteredTokens;
124 FilteredTokens.reserve(MI->tokens().size());
125 for (auto &T : MI->tokens())
126 if (!T.isOneOf(tok::l_paren, tok::r_paren))
127 FilteredTokens.push_back(T);
128
129 // Parse an integer at the end of the macro definition.
130 const Token &T = FilteredTokens.back();
131 // FIXME: EOF macro token coming from a PCH file on macOS while marked as
132 // literal, doesn't contain any literal data
133 if (!T.isLiteral() || !T.getLiteralData())
134 return llvm::None;
135 StringRef ValueStr = StringRef(T.getLiteralData(), T.getLength());
136 llvm::APInt IntValue;
137 constexpr unsigned AutoSenseRadix = 0;
138 if (ValueStr.getAsInteger(AutoSenseRadix, IntValue))
139 return llvm::None;
140
141 // Parse an optional minus sign.
142 size_t Size = FilteredTokens.size();
143 if (Size >= 2) {
144 if (FilteredTokens[Size - 2].is(tok::minus))
145 IntValue = -IntValue;
146 }
147
148 return IntValue.getSExtValue();
149}
150
151OperatorKind operationKindFromOverloadedOperator(OverloadedOperatorKind OOK,
152 bool IsBinary) {
153 llvm::StringMap<BinaryOperatorKind> BinOps{
154#define BINARY_OPERATION(Name, Spelling) {Spelling, BO_##Name},
155#include "clang/AST/OperationKinds.def"
156 };
157 llvm::StringMap<UnaryOperatorKind> UnOps{
158#define UNARY_OPERATION(Name, Spelling) {Spelling, UO_##Name},
159#include "clang/AST/OperationKinds.def"
160 };
161
162 switch (OOK) {
163#define OVERLOADED_OPERATOR(Name, Spelling, Token, Unary, Binary, MemberOnly) \
164 case OO_##Name: \
165 if (IsBinary) { \
166 auto BinOpIt = BinOps.find(Spelling); \
167 if (BinOpIt != BinOps.end()) \
168 return OperatorKind(BinOpIt->second); \
169 else \
170 llvm_unreachable("operator was expected to be binary but is not"); \
171 } else { \
172 auto UnOpIt = UnOps.find(Spelling); \
173 if (UnOpIt != UnOps.end()) \
174 return OperatorKind(UnOpIt->second); \
175 else \
176 llvm_unreachable("operator was expected to be unary but is not"); \
177 } \
178 break;
179#include "clang/Basic/OperatorKinds.def"
180 default:
181 llvm_unreachable("unexpected operator kind");
182 }
183}
184
185} // namespace ento
186} // namespace clang
187

source code of clang/lib/StaticAnalyzer/Core/CheckerHelpers.cpp