clang  11.0.0git
AnyCall.h
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1 //=== AnyCall.h - Abstraction over different callables --------*- 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 // A utility class for performing generic operations over different callables.
10 //
11 //===----------------------------------------------------------------------===//
12 //
13 #ifndef LLVM_CLANG_ANALYSIS_ANY_CALL_H
14 #define LLVM_CLANG_ANALYSIS_ANY_CALL_H
15 
16 #include "clang/AST/Decl.h"
17 #include "clang/AST/ExprCXX.h"
18 #include "clang/AST/ExprObjC.h"
19 
20 namespace clang {
21 
22 /// An instance of this class corresponds to a call.
23 /// It might be a syntactically-concrete call, done as a part of evaluating an
24 /// expression, or it may be an abstract callee with no associated expression.
25 class AnyCall {
26 public:
27  enum Kind {
28  /// A function, function pointer, or a C++ method call
29  Function,
30 
31  /// A call to an Objective-C method
32  ObjCMethod,
33 
34  /// A call to an Objective-C block
35  Block,
36 
37  /// An implicit C++ destructor call (called implicitly
38  /// or by operator 'delete')
39  Destructor,
40 
41  /// An implicit or explicit C++ constructor call
43 
44  /// A C++ inherited constructor produced by a "using T::T" directive
45  InheritedConstructor,
46 
47  /// A C++ allocation function call (operator `new`), via C++ new-expression
48  Allocator,
49 
50  /// A C++ deallocation function call (operator `delete`), via C++
51  /// delete-expression
52  Deallocator
53  };
54 
55 private:
56  /// Either expression or declaration (but not both at the same time)
57  /// can be null.
58 
59  /// Call expression, is null when is not known (then declaration is non-null),
60  /// or for implicit destructor calls (when no expression exists.)
61  const Expr *E = nullptr;
62 
63  /// Corresponds to a statically known declaration of the called function,
64  /// or null if it is not known (e.g. for a function pointer).
65  const Decl *D = nullptr;
66  Kind K;
67 
68 public:
69  AnyCall(const CallExpr *CE) : E(CE) {
70  D = CE->getCalleeDecl();
71  K = (CE->getCallee()->getType()->getAs<BlockPointerType>()) ? Block
72  : Function;
73  if (D && ((K == Function && !isa<FunctionDecl>(D)) ||
74  (K == Block && !isa<BlockDecl>(D))))
75  D = nullptr;
76  }
77 
78  AnyCall(const ObjCMessageExpr *ME)
79  : E(ME), D(ME->getMethodDecl()), K(ObjCMethod) {}
80 
81  AnyCall(const CXXNewExpr *NE)
82  : E(NE), D(NE->getOperatorNew()), K(Allocator) {}
83 
84  AnyCall(const CXXDeleteExpr *NE)
85  : E(NE), D(NE->getOperatorDelete()), K(Deallocator) {}
86 
87  AnyCall(const CXXConstructExpr *NE)
88  : E(NE), D(NE->getConstructor()), K(Constructor) {}
89 
90  AnyCall(const CXXInheritedCtorInitExpr *CIE)
91  : E(CIE), D(CIE->getConstructor()), K(InheritedConstructor) {}
92 
93  AnyCall(const CXXDestructorDecl *D) : E(nullptr), D(D), K(Destructor) {}
94 
95  AnyCall(const CXXConstructorDecl *D) : E(nullptr), D(D), K(Constructor) {}
96 
97  AnyCall(const ObjCMethodDecl *D) : E(nullptr), D(D), K(ObjCMethod) {}
98 
99  AnyCall(const FunctionDecl *D) : E(nullptr), D(D) {
100  if (isa<CXXConstructorDecl>(D)) {
101  K = Constructor;
102  } else if (isa <CXXDestructorDecl>(D)) {
103  K = Destructor;
104  } else {
105  K = Function;
106  }
107 
108  }
109 
110  /// If {@code E} is a generic call (to ObjC method /function/block/etc),
111  /// return a constructed {@code AnyCall} object. Return None otherwise.
112  static Optional<AnyCall> forExpr(const Expr *E) {
113  if (const auto *ME = dyn_cast<ObjCMessageExpr>(E)) {
114  return AnyCall(ME);
115  } else if (const auto *CE = dyn_cast<CallExpr>(E)) {
116  return AnyCall(CE);
117  } else if (const auto *CXNE = dyn_cast<CXXNewExpr>(E)) {
118  return AnyCall(CXNE);
119  } else if (const auto *CXDE = dyn_cast<CXXDeleteExpr>(E)) {
120  return AnyCall(CXDE);
121  } else if (const auto *CXCE = dyn_cast<CXXConstructExpr>(E)) {
122  return AnyCall(CXCE);
123  } else if (const auto *CXCIE = dyn_cast<CXXInheritedCtorInitExpr>(E)) {
124  return AnyCall(CXCIE);
125  } else {
126  return None;
127  }
128  }
129 
130  /// If {@code D} is a callable (Objective-C method or a function), return
131  /// a constructed {@code AnyCall} object. Return None otherwise.
132  // FIXME: block support.
133  static Optional<AnyCall> forDecl(const Decl *D) {
134  if (const auto *FD = dyn_cast<FunctionDecl>(D)) {
135  return AnyCall(FD);
136  } else if (const auto *MD = dyn_cast<ObjCMethodDecl>(D)) {
137  return AnyCall(MD);
138  }
139  return None;
140  }
141 
142  /// \returns formal parameters for direct calls (including virtual calls)
143  ArrayRef<ParmVarDecl *> parameters() const {
144  if (!D)
145  return None;
146 
147  if (const auto *FD = dyn_cast<FunctionDecl>(D)) {
148  return FD->parameters();
149  } else if (const auto *MD = dyn_cast<ObjCMethodDecl>(D)) {
150  return MD->parameters();
151  } else if (const auto *BD = dyn_cast<BlockDecl>(D)) {
152  return BD->parameters();
153  } else {
154  return None;
155  }
156  }
157 
158  using param_const_iterator = ArrayRef<ParmVarDecl *>::const_iterator;
159  param_const_iterator param_begin() const { return parameters().begin(); }
160  param_const_iterator param_end() const { return parameters().end(); }
161  size_t param_size() const { return parameters().size(); }
162  bool param_empty() const { return parameters().empty(); }
163 
164  QualType getReturnType(ASTContext &Ctx) const {
165  switch (K) {
166  case Function:
167  if (E)
168  return cast<CallExpr>(E)->getCallReturnType(Ctx);
169  return cast<FunctionDecl>(D)->getReturnType();
170  case ObjCMethod:
171  if (E)
172  return cast<ObjCMessageExpr>(E)->getCallReturnType(Ctx);
173  return cast<ObjCMethodDecl>(D)->getReturnType();
174  case Block:
175  // FIXME: BlockDecl does not know its return type,
176  // hence the asymmetry with the function and method cases above.
177  return cast<CallExpr>(E)->getCallReturnType(Ctx);
178  case Destructor:
179  case Constructor:
180  case InheritedConstructor:
181  case Allocator:
182  case Deallocator:
183  return cast<FunctionDecl>(D)->getReturnType();
184  }
185  llvm_unreachable("Unknown AnyCall::Kind");
186  }
187 
188  /// \returns Function identifier if it is a named declaration,
189  /// {@code nullptr} otherwise.
190  const IdentifierInfo *getIdentifier() const {
191  if (const auto *ND = dyn_cast_or_null<NamedDecl>(D))
192  return ND->getIdentifier();
193  return nullptr;
194  }
195 
196  const Decl *getDecl() const {
197  return D;
198  }
199 
200  const Expr *getExpr() const {
201  return E;
202  }
203 
204  Kind getKind() const {
205  return K;
206  }
207 
208  void dump() const {
209  if (E)
210  E->dump();
211  if (D)
212  D->dump();
213  }
214 };
215 
216 }
217 
218 #endif // LLVM_CLANG_ANALYSIS_ANY_CALL_H
The l-value was an access to a declared entity or something equivalently strong, like the address of ...
Defines the clang::Expr interface and subclasses for C++ expressions.
static void dump(llvm::raw_ostream &OS, StringRef FunctionName, ArrayRef< CounterExpression > Expressions, ArrayRef< CounterMappingRegion > Regions)
static StringRef getIdentifier(const Token &Tok)
Kind
Dataflow Directional Tag Classes.
bool NE(InterpState &S, CodePtr OpPC)
Definition: Interp.h:223
static Decl::Kind getKind(const Decl *D)
Definition: DeclBase.cpp:996