Revert r194865 and r194874.

This change is incorrect. If you delete virtual destructor of both a base class
and a subclass, then the following code:
  Base *foo = new Child();
  delete foo;
will not cause the destructor for members of Child class. As a result, I observe
plently of memory leaks. Notable examples I investigated are:
ObjectBuffer and ObjectBufferStream, AttributeImpl and StringSAttributeImpl.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194997 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/CodeGen/MachineRegisterInfo.h

@@ -30,9 +30,8 @@ class PSetIterator;
 class MachineRegisterInfo {
 public:
   class Delegate {
-    virtual void anchor();
   public:
-    virtual void MRI_NoteNewVirtualRegister(unsigned Reg) = 0;
+    virtual void MRI_NoteNewVirtualRegister(unsigned Reg) {}
 
     virtual ~Delegate() {}
   };

include/llvm/CodeGen/MachineScheduler.h

@@ -164,7 +164,6 @@ struct MachineSchedPolicy {
 /// Initialization sequence:
 ///   initPolicy -> shouldTrackPressure -> initialize(DAG) -> registerRoots
 class MachineSchedStrategy {
-  virtual void anchor();
 public:
   virtual ~MachineSchedStrategy() {}
 
@@ -263,7 +262,6 @@ public:
 
 /// Mutate the DAG as a postpass after normal DAG building.
 class ScheduleDAGMutation {
-  virtual void anchor();
 public:
   virtual ~ScheduleDAGMutation() {}
 

include/llvm/ExecutionEngine/ObjectBuffer.h

@@ -33,6 +33,7 @@ class ObjectBuffer {
 public:
   ObjectBuffer() {}
   ObjectBuffer(MemoryBuffer* Buf) : Buffer(Buf) {}
+  virtual ~ObjectBuffer() {}
 
   /// getMemBuffer - Like MemoryBuffer::getMemBuffer() this function
   /// returns a pointer to an object that is owned by the caller. However,
@@ -57,6 +58,7 @@ protected:
 class ObjectBufferStream : public ObjectBuffer {
 public:
   ObjectBufferStream() : OS(SV) {}
+  virtual ~ObjectBufferStream() {}
 
   raw_ostream &getOStream() { return OS; }
   void flush()

include/llvm/ExecutionEngine/ObjectCache.h

@@ -20,7 +20,6 @@ class Module;
 /// ExecutionEngine for the purpose of avoiding compilation for Modules that
 /// have already been compiled and an object file is available.
 class ObjectCache {
-  virtual void anchor();
 public:
   ObjectCache() { }
 

include/llvm/ExecutionEngine/ObjectImage.h

@@ -25,7 +25,6 @@ namespace llvm {
 class ObjectImage {
   ObjectImage() LLVM_DELETED_FUNCTION;
   ObjectImage(const ObjectImage &other) LLVM_DELETED_FUNCTION;
-  virtual void anchor();
 
 protected:
   OwningPtr<ObjectBuffer> Buffer;

include/llvm/MC/MCAtom.h

@@ -32,7 +32,6 @@ class MCDataAtom;
 /// \brief Represents a contiguous range of either instructions (a TextAtom)
 /// or data (a DataAtom).  Address ranges are expressed as _closed_ intervals.
 class MCAtom {
-  virtual void anchor();
 public:
   virtual ~MCAtom() {}
 

include/llvm/MC/MCStreamer.h

@@ -76,7 +76,6 @@ public:
 // FIXME: declared here because it is used from
 // lib/CodeGen/AsmPrinter/ARMException.cpp.
 class ARMTargetStreamer : public MCTargetStreamer {
-  virtual void anchor();
 public:
   virtual void emitFnStart() = 0;
   virtual void emitFnEnd() = 0;

include/llvm/MC/MCWinCOFFObjectWriter.h

@@ -19,8 +19,6 @@ namespace llvm {
   class MCWinCOFFObjectTargetWriter {
     const unsigned Machine;
 
-    virtual void anchor();
-
   protected:
     MCWinCOFFObjectTargetWriter(unsigned Machine_);
 

include/llvm/Support/CommandLine.h

@@ -350,9 +350,6 @@ struct cat {
 struct GenericOptionValue {
   virtual ~GenericOptionValue() {}
   virtual bool compare(const GenericOptionValue &V) const = 0;
-
-private:
-  virtual void anchor();
 };
 
 template<class DataType> struct OptionValue;
@@ -1755,7 +1752,6 @@ void getRegisteredOptions(StringMap<Option*> &Map);
 /// \brief Saves strings in the inheritor's stable storage and returns a stable
 /// raw character pointer.
 class StringSaver {
-  virtual void anchor();
 public:
   virtual const char *SaveString(const char *Str) = 0;
   virtual ~StringSaver() {};  // Pacify -Wnon-virtual-dtor.

include/llvm/Support/ValueHandle.h

@@ -339,7 +339,6 @@ public:
 /// rearrange itself when the pointer changes).  Unlike ValueHandleBase, this
 /// class has a vtable and a virtual destructor.
 class CallbackVH : public ValueHandleBase {
-  virtual void anchor();
 protected:
   CallbackVH(const CallbackVH &RHS)
     : ValueHandleBase(Callback, RHS) {}
@@ -366,13 +365,13 @@ public:
   ///
   /// All implementations must remove the reference from this object to the
   /// Value that's being destroyed.
-  virtual void deleted() { setValPtr(NULL); }
+  virtual void deleted();
 
   /// Called when this->getValPtr()->replaceAllUsesWith(new_value) is called,
   /// _before_ any of the uses have actually been replaced.  If WeakVH were
   /// implemented as a CallbackVH, it would use this method to call
   /// setValPtr(new_value).  AssertingVH would do nothing in this method.
-  virtual void allUsesReplacedWith(Value *) {}
+  virtual void allUsesReplacedWith(Value *);
 };
 
 } // End llvm namespace

include/llvm/Support/YAMLParser.h

@@ -105,7 +105,6 @@ private:
 
 /// @brief Abstract base class for all Nodes.
 class Node {
-   virtual void anchor();
 public:
   enum NodeKind {
     NK_Null,
@@ -176,7 +175,6 @@ private:
 /// Example:
 ///   !!null null
 class NullNode : public Node {
-  virtual void anchor();
 public:
   NullNode(OwningPtr<Document> &D)
       : Node(NK_Null, D, StringRef(), StringRef()) {}
@@ -192,7 +190,6 @@ public:
 /// Example:
 ///   Adena
 class ScalarNode : public Node {
-  virtual void anchor();
 public:
   ScalarNode(OwningPtr<Document> &D, StringRef Anchor, StringRef Tag,
              StringRef Val)
@@ -234,7 +231,6 @@ private:
 /// Example:
 ///   Section: .text
 class KeyValueNode : public Node {
-  virtual void anchor();
 public:
   KeyValueNode(OwningPtr<Document> &D)
     : Node(NK_KeyValue, D, StringRef(), StringRef())
@@ -346,7 +342,6 @@ void skip(CollectionType &C) {
 ///   Name: _main
 ///   Scope: Global
 class MappingNode : public Node {
-  virtual void anchor();
 public:
   enum MappingType {
     MT_Block,
@@ -396,7 +391,6 @@ private:
 ///   - Hello
 ///   - World
 class SequenceNode : public Node {
-  virtual void anchor();
 public:
   enum SequenceType {
     ST_Block,
@@ -452,7 +446,6 @@ private:
 /// Example:
 ///   *AnchorName
 class AliasNode : public Node {
-  virtual void anchor();
 public:
   AliasNode(OwningPtr<Document> &D, StringRef Val)
     : Node(NK_Alias, D, StringRef(), StringRef()), Name(Val) {}

include/llvm/Support/YAMLTraits.h

@@ -723,7 +723,6 @@ private:
   virtual bool canElideEmptySequence();
 
   class HNode {
-    virtual void anchor();
   public:
     HNode(Node *n) : _node(n) { }
     virtual ~HNode() { }
@@ -733,9 +732,9 @@ private:
   };
 
   class EmptyHNode : public HNode {
-    virtual void anchor();
   public:
     EmptyHNode(Node *n) : HNode(n) { }
+    virtual ~EmptyHNode() {}
     static inline bool classof(const HNode *n) {
       return NullNode::classof(n->_node);
     }
@@ -743,9 +742,9 @@ private:
   };
 
   class ScalarHNode : public HNode {
-    virtual void anchor();
   public:
     ScalarHNode(Node *n, StringRef s) : HNode(n), _value(s) { }
+    virtual ~ScalarHNode() { }
 
     StringRef value() const { return _value; }
 
@@ -758,7 +757,6 @@ private:
   };
 
   class MapHNode : public HNode {
-    virtual void anchor();
   public:
     MapHNode(Node *n) : HNode(n) { }
     virtual ~MapHNode();
@@ -777,7 +775,6 @@ private:
   };
 
   class SequenceHNode : public HNode {
-    virtual void anchor();
   public:
     SequenceHNode(Node *n) : HNode(n) { }
     virtual ~SequenceHNode();