[AST] Migrate away from PointerUnion::{is,get} (NFC) (#119523)

Note that PointerUnion::{is,get} have been soft deprecated in
PointerUnion.h:

  // FIXME: Replace the uses of is(), get() and dyn_cast() with
  //        isa<T>, cast<T> and the llvm::dyn_cast<T>

I'm not touching PointerUnion::dyn_cast for now because it's a bit
complicated; we could blindly migrate it to dyn_cast_if_present, but
we should probably use dyn_cast when the operand is known to be
non-null.

Author: kazutakahirata

clang/include/clang/AST/Decl.h

@@ -747,9 +747,9 @@ class DeclaratorDecl : public ValueDecl {
   /// ignoring outer template declarations.
   SourceLocation InnerLocStart;
 
-  bool hasExtInfo() const { return DeclInfo.is<ExtInfo*>(); }
-  ExtInfo *getExtInfo() { return DeclInfo.get<ExtInfo*>(); }
-  const ExtInfo *getExtInfo() const { return DeclInfo.get<ExtInfo*>(); }
+  bool hasExtInfo() const { return isa<ExtInfo *>(DeclInfo); }
+  ExtInfo *getExtInfo() { return cast<ExtInfo *>(DeclInfo); }
+  const ExtInfo *getExtInfo() const { return cast<ExtInfo *>(DeclInfo); }
 
 protected:
   DeclaratorDecl(Kind DK, DeclContext *DC, SourceLocation L,
@@ -762,9 +762,8 @@ class DeclaratorDecl : public ValueDecl {
   friend class ASTDeclWriter;
 
   TypeSourceInfo *getTypeSourceInfo() const {
-    return hasExtInfo()
-      ? getExtInfo()->TInfo
-      : DeclInfo.get<TypeSourceInfo*>();
+    return hasExtInfo() ? getExtInfo()->TInfo
+                        : cast<TypeSourceInfo *>(DeclInfo);
   }
 
   void setTypeSourceInfo(TypeSourceInfo *TI) {
@@ -3587,10 +3586,10 @@ class TagDecl : public TypeDecl,
   /// otherwise, it is a null (TypedefNameDecl) pointer.
   llvm::PointerUnion<TypedefNameDecl *, ExtInfo *> TypedefNameDeclOrQualifier;
 
-  bool hasExtInfo() const { return TypedefNameDeclOrQualifier.is<ExtInfo *>(); }
-  ExtInfo *getExtInfo() { return TypedefNameDeclOrQualifier.get<ExtInfo *>(); }
+  bool hasExtInfo() const { return isa<ExtInfo *>(TypedefNameDeclOrQualifier); }
+  ExtInfo *getExtInfo() { return cast<ExtInfo *>(TypedefNameDeclOrQualifier); }
   const ExtInfo *getExtInfo() const {
-    return TypedefNameDeclOrQualifier.get<ExtInfo *>();
+    return cast<ExtInfo *>(TypedefNameDeclOrQualifier);
   }
 
 protected:
@@ -3793,7 +3792,7 @@ class TagDecl : public TypeDecl,
 
   TypedefNameDecl *getTypedefNameForAnonDecl() const {
     return hasExtInfo() ? nullptr
-                        : TypedefNameDeclOrQualifier.get<TypedefNameDecl *>();
+                        : cast<TypedefNameDecl *>(TypedefNameDeclOrQualifier);
   }
 
   void setTypedefNameForAnonDecl(TypedefNameDecl *TDD);
@@ -4011,7 +4010,7 @@ class EnumDecl : public TagDecl {
       return QualType();
     if (const Type *T = IntegerType.dyn_cast<const Type*>())
       return QualType(T, 0);
-    return IntegerType.get<TypeSourceInfo*>()->getType().getUnqualifiedType();
+    return cast<TypeSourceInfo *>(IntegerType)->getType().getUnqualifiedType();
   }
 
   /// Set the underlying integer type.

clang/include/clang/AST/DeclBase.h

@@ -271,16 +271,12 @@ class alignas(8) Decl {
   ///                // LexicalDC == global namespace
   llvm::PointerUnion<DeclContext*, MultipleDC*> DeclCtx;
 
-  bool isInSemaDC() const { return DeclCtx.is<DeclContext*>(); }
-  bool isOutOfSemaDC() const { return DeclCtx.is<MultipleDC*>(); }
+  bool isInSemaDC() const { return isa<DeclContext *>(DeclCtx); }
+  bool isOutOfSemaDC() const { return isa<MultipleDC *>(DeclCtx); }
 
-  MultipleDC *getMultipleDC() const {
-    return DeclCtx.get<MultipleDC*>();
-  }
+  MultipleDC *getMultipleDC() const { return cast<MultipleDC *>(DeclCtx); }
 
-  DeclContext *getSemanticDC() const {
-    return DeclCtx.get<DeclContext*>();
-  }
+  DeclContext *getSemanticDC() const { return cast<DeclContext *>(DeclCtx); }
 
   /// Loc - The location of this decl.
   SourceLocation Loc;
@@ -1340,7 +1336,7 @@ class DeclListNode {
       assert(Ptr && "dereferencing end() iterator");
       if (DeclListNode *CurNode = Ptr.dyn_cast<DeclListNode*>())
         return CurNode->D;
-      return Ptr.get<NamedDecl*>();
+      return cast<NamedDecl *>(Ptr);
     }
     void operator->() const { } // Unsupported.
     bool operator==(const iterator &X) const { return Ptr == X.Ptr; }

clang/include/clang/AST/DeclCXX.h

@@ -2388,19 +2388,19 @@ class CXXCtorInitializer final {
 
   /// Determine whether this initializer is initializing a base class.
   bool isBaseInitializer() const {
-    return Initializee.is<TypeSourceInfo*>() && !IsDelegating;
+    return isa<TypeSourceInfo *>(Initializee) && !IsDelegating;
   }
 
   /// Determine whether this initializer is initializing a non-static
   /// data member.
-  bool isMemberInitializer() const { return Initializee.is<FieldDecl*>(); }
+  bool isMemberInitializer() const { return isa<FieldDecl *>(Initializee); }
 
   bool isAnyMemberInitializer() const {
     return isMemberInitializer() || isIndirectMemberInitializer();
   }
 
   bool isIndirectMemberInitializer() const {
-    return Initializee.is<IndirectFieldDecl*>();
+    return isa<IndirectFieldDecl *>(Initializee);
   }
 
   /// Determine whether this initializer is an implicit initializer
@@ -2416,7 +2416,7 @@ class CXXCtorInitializer final {
   /// Determine whether this initializer is creating a delegating
   /// constructor.
   bool isDelegatingInitializer() const {
-    return Initializee.is<TypeSourceInfo*>() && IsDelegating;
+    return isa<TypeSourceInfo *>(Initializee) && IsDelegating;
   }
 
   /// Determine whether this initializer is a pack expansion.
@@ -2457,21 +2457,21 @@ class CXXCtorInitializer final {
   /// non-static data member being initialized. Otherwise, returns null.
   FieldDecl *getMember() const {
     if (isMemberInitializer())
-      return Initializee.get<FieldDecl*>();
+      return cast<FieldDecl *>(Initializee);
     return nullptr;
   }
 
   FieldDecl *getAnyMember() const {
     if (isMemberInitializer())
-      return Initializee.get<FieldDecl*>();
+      return cast<FieldDecl *>(Initializee);
     if (isIndirectMemberInitializer())
-      return Initializee.get<IndirectFieldDecl*>()->getAnonField();
+      return cast<IndirectFieldDecl *>(Initializee)->getAnonField();
     return nullptr;
   }
 
   IndirectFieldDecl *getIndirectMember() const {
     if (isIndirectMemberInitializer())
-      return Initializee.get<IndirectFieldDecl*>();
+      return cast<IndirectFieldDecl *>(Initializee);
     return nullptr;
   }
 

clang/include/clang/AST/DeclTemplate.h

@@ -1965,7 +1965,7 @@ class ClassTemplateSpecializationDecl : public CXXRecordDecl,
             SpecializedTemplate.dyn_cast<SpecializedPartialSpecialization *>())
       return PartialSpec->PartialSpecialization;
 
-    return SpecializedTemplate.get<ClassTemplateDecl*>();
+    return cast<ClassTemplateDecl *>(SpecializedTemplate);
   }
 
   /// Retrieve the set of template arguments that should be used
@@ -2013,7 +2013,7 @@ class ClassTemplateSpecializationDecl : public CXXRecordDecl,
   const ASTTemplateArgumentListInfo *getTemplateArgsAsWritten() const {
     if (auto *Info = ExplicitInfo.dyn_cast<ExplicitInstantiationInfo *>())
       return Info->TemplateArgsAsWritten;
-    return ExplicitInfo.get<const ASTTemplateArgumentListInfo *>();
+    return cast<const ASTTemplateArgumentListInfo *>(ExplicitInfo);
   }
 
   /// Set the template argument list as written in the sources.
@@ -2734,7 +2734,7 @@ class VarTemplateSpecializationDecl : public VarDecl,
             SpecializedTemplate.dyn_cast<SpecializedPartialSpecialization *>())
       return PartialSpec->PartialSpecialization;
 
-    return SpecializedTemplate.get<VarTemplateDecl *>();
+    return cast<VarTemplateDecl *>(SpecializedTemplate);
   }
 
   /// Retrieve the set of template arguments that should be used
@@ -2782,7 +2782,7 @@ class VarTemplateSpecializationDecl : public VarDecl,
   const ASTTemplateArgumentListInfo *getTemplateArgsAsWritten() const {
     if (auto *Info = ExplicitInfo.dyn_cast<ExplicitInstantiationInfo *>())
       return Info->TemplateArgsAsWritten;
-    return ExplicitInfo.get<const ASTTemplateArgumentListInfo *>();
+    return cast<const ASTTemplateArgumentListInfo *>(ExplicitInfo);
   }
 
   /// Set the template argument list as written in the sources.
@@ -3309,7 +3309,7 @@ inline NamedDecl *getAsNamedDecl(TemplateParameter P) {
     return PD;
   if (auto *PD = P.dyn_cast<NonTypeTemplateParmDecl *>())
     return PD;
-  return P.get<TemplateTemplateParmDecl *>();
+  return cast<TemplateTemplateParmDecl *>(P);
 }
 
 inline TemplateDecl *getAsTypeTemplateDecl(Decl *D) {

clang/include/clang/AST/ExprCXX.h

@@ -878,7 +878,7 @@ class CXXTypeidExpr : public Expr {
   /// object. This is not a strong guarantee.
   bool isMostDerived(const ASTContext &Context) const;
 
-  bool isTypeOperand() const { return Operand.is<TypeSourceInfo *>(); }
+  bool isTypeOperand() const { return isa<TypeSourceInfo *>(Operand); }
 
   /// Retrieves the type operand of this typeid() expression after
   /// various required adjustments (removing reference types, cv-qualifiers).
@@ -887,11 +887,11 @@ class CXXTypeidExpr : public Expr {
   /// Retrieve source information for the type operand.
   TypeSourceInfo *getTypeOperandSourceInfo() const {
     assert(isTypeOperand() && "Cannot call getTypeOperand for typeid(expr)");
-    return Operand.get<TypeSourceInfo *>();
+    return cast<TypeSourceInfo *>(Operand);
   }
   Expr *getExprOperand() const {
     assert(!isTypeOperand() && "Cannot call getExprOperand for typeid(type)");
-    return static_cast<Expr*>(Operand.get<Stmt *>());
+    return static_cast<Expr *>(cast<Stmt *>(Operand));
   }
 
   SourceLocation getBeginLoc() const LLVM_READONLY { return Range.getBegin(); }
@@ -1093,7 +1093,7 @@ class CXXUuidofExpr : public Expr {
       Operand = (TypeSourceInfo*)nullptr;
   }
 
-  bool isTypeOperand() const { return Operand.is<TypeSourceInfo *>(); }
+  bool isTypeOperand() const { return isa<TypeSourceInfo *>(Operand); }
 
   /// Retrieves the type operand of this __uuidof() expression after
   /// various required adjustments (removing reference types, cv-qualifiers).
@@ -1102,11 +1102,11 @@ class CXXUuidofExpr : public Expr {
   /// Retrieve source information for the type operand.
   TypeSourceInfo *getTypeOperandSourceInfo() const {
     assert(isTypeOperand() && "Cannot call getTypeOperand for __uuidof(expr)");
-    return Operand.get<TypeSourceInfo *>();
+    return cast<TypeSourceInfo *>(Operand);
   }
   Expr *getExprOperand() const {
     assert(!isTypeOperand() && "Cannot call getExprOperand for __uuidof(type)");
-    return static_cast<Expr*>(Operand.get<Stmt *>());
+    return static_cast<Expr *>(cast<Stmt *>(Operand));
   }
 
   MSGuidDecl *getGuidDecl() const { return Guid; }
@@ -4750,24 +4750,24 @@ class MaterializeTemporaryExpr : public Expr {
   /// be materialized into a glvalue.
   Expr *getSubExpr() const {
     return cast<Expr>(
-        State.is<Stmt *>()
-            ? State.get<Stmt *>()
-            : State.get<LifetimeExtendedTemporaryDecl *>()->getTemporaryExpr());
+        isa<Stmt *>(State)
+            ? cast<Stmt *>(State)
+            : cast<LifetimeExtendedTemporaryDecl *>(State)->getTemporaryExpr());
   }
 
   /// Retrieve the storage duration for the materialized temporary.
   StorageDuration getStorageDuration() const {
-    return State.is<Stmt *>() ? SD_FullExpression
-                              : State.get<LifetimeExtendedTemporaryDecl *>()
+    return isa<Stmt *>(State) ? SD_FullExpression
+                              : cast<LifetimeExtendedTemporaryDecl *>(State)
                                     ->getStorageDuration();
   }
 
   /// Get the storage for the constant value of a materialized temporary
   /// of static storage duration.
   APValue *getOrCreateValue(bool MayCreate) const {
-    assert(State.is<LifetimeExtendedTemporaryDecl *>() &&
+    assert(isa<LifetimeExtendedTemporaryDecl *>(State) &&
            "the temporary has not been lifetime extended");
-    return State.get<LifetimeExtendedTemporaryDecl *>()->getOrCreateValue(
+    return cast<LifetimeExtendedTemporaryDecl *>(State)->getOrCreateValue(
         MayCreate);
   }
 
@@ -4782,8 +4782,8 @@ class MaterializeTemporaryExpr : public Expr {
   /// Get the declaration which triggered the lifetime-extension of this
   /// temporary, if any.
   ValueDecl *getExtendingDecl() {
-    return State.is<Stmt *>() ? nullptr
-                              : State.get<LifetimeExtendedTemporaryDecl *>()
+    return isa<Stmt *>(State) ? nullptr
+                              : cast<LifetimeExtendedTemporaryDecl *>(State)
                                     ->getExtendingDecl();
   }
   const ValueDecl *getExtendingDecl() const {
@@ -4793,8 +4793,8 @@ class MaterializeTemporaryExpr : public Expr {
   void setExtendingDecl(ValueDecl *ExtendedBy, unsigned ManglingNumber);
 
   unsigned getManglingNumber() const {
-    return State.is<Stmt *>() ? 0
-                              : State.get<LifetimeExtendedTemporaryDecl *>()
+    return isa<Stmt *>(State) ? 0
+                              : cast<LifetimeExtendedTemporaryDecl *>(State)
                                     ->getManglingNumber();
   }
 
@@ -4820,17 +4820,17 @@ class MaterializeTemporaryExpr : public Expr {
 
   // Iterators
   child_range children() {
-    return State.is<Stmt *>()
+    return isa<Stmt *>(State)
                ? child_range(State.getAddrOfPtr1(), State.getAddrOfPtr1() + 1)
-               : State.get<LifetimeExtendedTemporaryDecl *>()->childrenExpr();
+               : cast<LifetimeExtendedTemporaryDecl *>(State)->childrenExpr();
   }
 
   const_child_range children() const {
-    return State.is<Stmt *>()
+    return isa<Stmt *>(State)
                ? const_child_range(State.getAddrOfPtr1(),
                                    State.getAddrOfPtr1() + 1)
                : const_cast<const LifetimeExtendedTemporaryDecl *>(
-                     State.get<LifetimeExtendedTemporaryDecl *>())
+                     cast<LifetimeExtendedTemporaryDecl *>(State))
                      ->childrenExpr();
   }
 };

clang/include/clang/AST/ExprConcepts.h

@@ -261,13 +261,13 @@ class TypeRequirement : public Requirement {
     assert(Status == SS_SubstitutionFailure &&
            "Attempted to get substitution diagnostic when there has been no "
            "substitution failure.");
-    return Value.get<SubstitutionDiagnostic *>();
+    return cast<SubstitutionDiagnostic *>(Value);
   }
 
   TypeSourceInfo *getType() const {
     assert(!isSubstitutionFailure() &&
            "Attempted to get type when there has been a substitution failure.");
-    return Value.get<TypeSourceInfo *>();
+    return cast<TypeSourceInfo *>(Value);
   }
 
   static bool classof(const Requirement *R) {
@@ -409,14 +409,14 @@ class ExprRequirement : public Requirement {
     assert(isExprSubstitutionFailure() &&
            "Attempted to get expression substitution diagnostic when there has "
            "been no expression substitution failure");
-    return Value.get<SubstitutionDiagnostic *>();
+    return cast<SubstitutionDiagnostic *>(Value);
   }
 
   Expr *getExpr() const {
     assert(!isExprSubstitutionFailure() &&
            "ExprRequirement has no expression because there has been a "
            "substitution failure.");
-    return Value.get<Expr *>();
+    return cast<Expr *>(Value);
   }
 
   static bool classof(const Requirement *R) {

clang/include/clang/AST/ExprObjC.h

@@ -752,28 +752,24 @@ class ObjCPropertyRefExpr : public Expr {
     setMethodRefFlag(MethodRef_Setter, val);
   }
 
-  const Expr *getBase() const {
-    return cast<Expr>(Receiver.get<Stmt*>());
-  }
-  Expr *getBase() {
-    return cast<Expr>(Receiver.get<Stmt*>());
-  }
+  const Expr *getBase() const { return cast<Expr>(cast<Stmt *>(Receiver)); }
+  Expr *getBase() { return cast<Expr>(cast<Stmt *>(Receiver)); }
 
   SourceLocation getLocation() const { return IdLoc; }
 
   SourceLocation getReceiverLocation() const { return ReceiverLoc; }
 
   QualType getSuperReceiverType() const {
-    return QualType(Receiver.get<const Type*>(), 0);
+    return QualType(cast<const Type *>(Receiver), 0);
   }
 
   ObjCInterfaceDecl *getClassReceiver() const {
-    return Receiver.get<ObjCInterfaceDecl*>();
+    return cast<ObjCInterfaceDecl *>(Receiver);
   }
 
-  bool isObjectReceiver() const { return Receiver.is<Stmt*>(); }
-  bool isSuperReceiver() const { return Receiver.is<const Type*>(); }
-  bool isClassReceiver() const { return Receiver.is<ObjCInterfaceDecl*>(); }
+  bool isObjectReceiver() const { return isa<Stmt *>(Receiver); }
+  bool isSuperReceiver() const { return isa<const Type *>(Receiver); }
+  bool isClassReceiver() const { return isa<ObjCInterfaceDecl *>(Receiver); }
 
   /// Determine the type of the base, regardless of the kind of receiver.
   QualType getReceiverType(const ASTContext &ctx) const;
@@ -787,7 +783,7 @@ class ObjCPropertyRefExpr : public Expr {
 
   // Iterators
   child_range children() {
-    if (Receiver.is<Stmt*>()) {
+    if (isa<Stmt *>(Receiver)) {
       Stmt **begin = reinterpret_cast<Stmt**>(&Receiver); // hack!
       return child_range(begin, begin+1);
     }