Simplify some implementations of get*Decl.

* NamedDecl and CXXMethodDecl were missing getMostRecentDecl.
* The const version can just forward to the non const.
* getMostRecentDecl can use cast instead of cast_or_null.

This then removes some casts from the callers.

llvm-svn: 193039

clang/include/clang/AST/Decl.h

@@ -273,6 +273,13 @@ public:
     return const_cast<NamedDecl*>(this)->getUnderlyingDecl();
   }
 
+  NamedDecl *getMostRecentDecl() {
+    return cast<NamedDecl>(Decl::getMostRecentDecl());
+  }
+  const NamedDecl *getMostRecentDecl() const {
+    return const_cast<NamedDecl*>(this)->getMostRecentDecl();
+  }
+
   static bool classof(const Decl *D) { return classofKind(D->getKind()); }
   static bool classofKind(Kind K) { return K >= firstNamed && K <= lastNamed; }
 };
@@ -2810,22 +2817,22 @@ public:
     return cast<EnumDecl>(TagDecl::getCanonicalDecl());
   }
   const EnumDecl *getCanonicalDecl() const {
-    return cast<EnumDecl>(TagDecl::getCanonicalDecl());
+    return const_cast<EnumDecl*>(this)->getCanonicalDecl();
   }
 
-  const EnumDecl *getPreviousDecl() const {
-    return cast_or_null<EnumDecl>(TagDecl::getPreviousDecl());
-  }
   EnumDecl *getPreviousDecl() {
     return cast_or_null<EnumDecl>(TagDecl::getPreviousDecl());
   }
-
-  const EnumDecl *getMostRecentDecl() const {
-    return cast<EnumDecl>(TagDecl::getMostRecentDecl());
+  const EnumDecl *getPreviousDecl() const {
+    return const_cast<EnumDecl*>(this)->getPreviousDecl();
   }
+
   EnumDecl *getMostRecentDecl() {
     return cast<EnumDecl>(TagDecl::getMostRecentDecl());
   }
+  const EnumDecl *getMostRecentDecl() const {
+    return const_cast<EnumDecl*>(this)->getMostRecentDecl();
+  }
 
   EnumDecl *getDefinition() const {
     return cast_or_null<EnumDecl>(TagDecl::getDefinition());
@@ -3020,19 +3027,19 @@ public:
                             IdentifierInfo *Id, RecordDecl* PrevDecl = 0);
   static RecordDecl *CreateDeserialized(const ASTContext &C, unsigned ID);
 
-  const RecordDecl *getPreviousDecl() const {
-    return cast_or_null<RecordDecl>(TagDecl::getPreviousDecl());
-  }
   RecordDecl *getPreviousDecl() {
     return cast_or_null<RecordDecl>(TagDecl::getPreviousDecl());
   }
-
-  const RecordDecl *getMostRecentDecl() const {
-    return cast<RecordDecl>(TagDecl::getMostRecentDecl());
+  const RecordDecl *getPreviousDecl() const {
+    return const_cast<RecordDecl*>(this)->getPreviousDecl();
   }
+
   RecordDecl *getMostRecentDecl() {
     return cast<RecordDecl>(TagDecl::getMostRecentDecl());
   }
+  const RecordDecl *getMostRecentDecl() const {
+    return const_cast<RecordDecl*>(this)->getMostRecentDecl();
+  }
 
   bool hasFlexibleArrayMember() const { return HasFlexibleArrayMember; }
   void setHasFlexibleArrayMember(bool V) { HasFlexibleArrayMember = V; }

clang/include/clang/AST/DeclCXX.h

@@ -641,18 +641,19 @@ public:
     return cast<CXXRecordDecl>(RecordDecl::getCanonicalDecl());
   }
 
-  const CXXRecordDecl *getPreviousDecl() const {
-    return cast_or_null<CXXRecordDecl>(RecordDecl::getPreviousDecl());
-  }
   CXXRecordDecl *getPreviousDecl() {
     return cast_or_null<CXXRecordDecl>(RecordDecl::getPreviousDecl());
   }
+  const CXXRecordDecl *getPreviousDecl() const {
+    return const_cast<CXXRecordDecl*>(this)->getPreviousDecl();
+  }
+
+  CXXRecordDecl *getMostRecentDecl() {
+    return cast<CXXRecordDecl>(RecordDecl::getMostRecentDecl());
+  }
 
   const CXXRecordDecl *getMostRecentDecl() const {
-    return cast_or_null<CXXRecordDecl>(RecordDecl::getMostRecentDecl());
-  }
-  CXXRecordDecl *getMostRecentDecl() {
-    return cast_or_null<CXXRecordDecl>(RecordDecl::getMostRecentDecl());
+    return const_cast<CXXRecordDecl*>(this)->getMostRecentDecl();
   }
 
   CXXRecordDecl *getDefinition() const {
@@ -1716,12 +1717,19 @@ public:
   /// \brief Determine whether this is a move assignment operator.
   bool isMoveAssignmentOperator() const;
 
-  const CXXMethodDecl *getCanonicalDecl() const {
-    return cast<CXXMethodDecl>(FunctionDecl::getCanonicalDecl());
-  }
   CXXMethodDecl *getCanonicalDecl() {
     return cast<CXXMethodDecl>(FunctionDecl::getCanonicalDecl());
   }
+  const CXXMethodDecl *getCanonicalDecl() const {
+    return const_cast<CXXMethodDecl*>(this)->getCanonicalDecl();
+  }
+
+  CXXMethodDecl *getMostRecentDecl() {
+    return cast<CXXMethodDecl>(FunctionDecl::getMostRecentDecl());
+  }
+  const CXXMethodDecl *getMostRecentDecl() const {
+    return const_cast<CXXMethodDecl*>(this)->getMostRecentDecl();
+  }
 
   /// True if this method is user-declared and was not
   /// deleted or defaulted on its first declaration.

clang/include/clang/AST/DeclTemplate.h

@@ -1449,8 +1449,7 @@ public:
                                     bool Qualified) const;
 
   ClassTemplateSpecializationDecl *getMostRecentDecl() {
-    CXXRecordDecl *Recent
-        = cast<CXXRecordDecl>(CXXRecordDecl::getMostRecentDecl());
+    CXXRecordDecl *Recent = CXXRecordDecl::getMostRecentDecl();
     while (!isa<ClassTemplateSpecializationDecl>(Recent)) {
       // FIXME: Does injected class name need to be in the redeclarations chain?
       assert(Recent->isInjectedClassName() && Recent->getPreviousDecl());
@@ -2310,7 +2309,7 @@ public:
                                     bool Qualified) const;
 
   VarTemplateSpecializationDecl *getMostRecentDecl() {
-    VarDecl *Recent = cast<VarDecl>(VarDecl::getMostRecentDecl());
+    VarDecl *Recent = VarDecl::getMostRecentDecl();
     return cast<VarTemplateSpecializationDecl>(Recent);
   }
 

clang/lib/AST/Decl.cpp

@@ -972,7 +972,7 @@ NamedDecl::getExplicitVisibility(ExplicitVisibilityKind kind) const {
                            kind);
 
   // Use the most recent declaration.
-  const NamedDecl *MostRecent = cast<NamedDecl>(this->getMostRecentDecl());
+  const NamedDecl *MostRecent = getMostRecentDecl();
   if (MostRecent != this)
     return MostRecent->getExplicitVisibility(kind);
 

clang/lib/Analysis/ThreadSafety.cpp

@@ -323,8 +323,7 @@ private:
     } else if (const CXXMemberCallExpr *CMCE = dyn_cast<CXXMemberCallExpr>(Exp)) {
       // When calling a function with a lock_returned attribute, replace
       // the function call with the expression in lock_returned.
-      const CXXMethodDecl* MD =
-        cast<CXXMethodDecl>(CMCE->getMethodDecl()->getMostRecentDecl());
+      const CXXMethodDecl *MD = CMCE->getMethodDecl()->getMostRecentDecl();
       if (LockReturnedAttr* At = MD->getAttr<LockReturnedAttr>()) {
         CallingContext LRCallCtx(CMCE->getMethodDecl());
         LRCallCtx.SelfArg = CMCE->getImplicitObjectArgument();
@@ -353,8 +352,7 @@ private:
       NodeVec[Root].setSize(Sz + 1);
       return Sz + 1;
     } else if (const CallExpr *CE = dyn_cast<CallExpr>(Exp)) {
-      const FunctionDecl* FD =
-        cast<FunctionDecl>(CE->getDirectCallee()->getMostRecentDecl());
+      const FunctionDecl *FD = CE->getDirectCallee()->getMostRecentDecl();
       if (LockReturnedAttr* At = FD->getAttr<LockReturnedAttr>()) {
         CallingContext LRCallCtx(CE->getDirectCallee());
         LRCallCtx.NumArgs = CE->getNumArgs();

clang/lib/Sema/SemaDecl.cpp

@@ -4487,7 +4487,7 @@ NamedDecl *Sema::findLocallyScopedExternCDecl(DeclarationName Name) {
   }
 
   NamedDecl *D = LocallyScopedExternCDecls.lookup(Name);
-  return D ? cast<NamedDecl>(D->getMostRecentDecl()) : 0;
+  return D ? D->getMostRecentDecl() : 0;
 }
 
 /// \brief Diagnose function specifiers on a declaration of an identifier that

clang/lib/Serialization/ASTReader.cpp

@@ -7580,7 +7580,7 @@ void ASTReader::FinishedDeserializing() {
 }
 
 void ASTReader::pushExternalDeclIntoScope(NamedDecl *D, DeclarationName Name) {
-  D = cast<NamedDecl>(D->getMostRecentDecl());
+  D = D->getMostRecentDecl();
 
   if (SemaObj->IdResolver.tryAddTopLevelDecl(D, Name) && SemaObj->TUScope) {
     SemaObj->TUScope->AddDecl(D);