Cleaup ValueHandle to no longer keep a PointerIntPair for the Value*.

This was used previously for metadata but is no longer needed there. Not
doing this simplifies ValueHandle and will make it easier to fix things
like AssertingVH's DenseMapInfo.

llvm-svn: 225487

llvm/include/llvm/IR/ValueHandle.h

@@ -56,55 +56,48 @@ private:
   PointerIntPair<ValueHandleBase**, 2, HandleBaseKind> PrevPair;
   ValueHandleBase *Next;
 
-  // A subclass may want to store some information along with the value
+  Value* V;
-  // pointer. Allow them to do this by making the value pointer a pointer-int
-  // pair. The 'setValPtrInt' and 'getValPtrInt' methods below give them this
-  // access.
-  PointerIntPair<Value*, 2> VP;
 
   ValueHandleBase(const ValueHandleBase&) LLVM_DELETED_FUNCTION;
 public:
   explicit ValueHandleBase(HandleBaseKind Kind)
-    : PrevPair(nullptr, Kind), Next(nullptr), VP(nullptr, 0) {}
+    : PrevPair(nullptr, Kind), Next(nullptr), V(nullptr) {}
   ValueHandleBase(HandleBaseKind Kind, Value *V)
-    : PrevPair(nullptr, Kind), Next(nullptr), VP(V, 0) {
+    : PrevPair(nullptr, Kind), Next(nullptr), V(V) {
-    if (isValid(VP.getPointer()))
+    if (isValid(V))
       AddToUseList();
   }
   ValueHandleBase(HandleBaseKind Kind, const ValueHandleBase &RHS)
-    : PrevPair(nullptr, Kind), Next(nullptr), VP(RHS.VP) {
+    : PrevPair(nullptr, Kind), Next(nullptr), V(RHS.V) {
-    if (isValid(VP.getPointer()))
+    if (isValid(V))
       AddToExistingUseList(RHS.getPrevPtr());
   }
   ~ValueHandleBase() {
-    if (isValid(VP.getPointer()))
+    if (isValid(V))
       RemoveFromUseList();
   }
 
   Value *operator=(Value *RHS) {
-    if (VP.getPointer() == RHS) return RHS;
+    if (V == RHS) return RHS;
-    if (isValid(VP.getPointer())) RemoveFromUseList();
+    if (isValid(V)) RemoveFromUseList();
-    VP.setPointer(RHS);
+    V = RHS;
-    if (isValid(VP.getPointer())) AddToUseList();
+    if (isValid(V)) AddToUseList();
     return RHS;
   }
 
   Value *operator=(const ValueHandleBase &RHS) {
-    if (VP.getPointer() == RHS.VP.getPointer()) return RHS.VP.getPointer();
+    if (V == RHS.V) return RHS.V;
-    if (isValid(VP.getPointer())) RemoveFromUseList();
+    if (isValid(V)) RemoveFromUseList();
-    VP.setPointer(RHS.VP.getPointer());
+    V = RHS.V;
-    if (isValid(VP.getPointer())) AddToExistingUseList(RHS.getPrevPtr());
+    if (isValid(V)) AddToExistingUseList(RHS.getPrevPtr());
-    return VP.getPointer();
+    return V;
   }
 
-  Value *operator->() const { return getValPtr(); }
+  Value *operator->() const { return V; }
-  Value &operator*() const { return *getValPtr(); }
+  Value &operator*() const { return *V; }
 
 protected:
-  Value *getValPtr() const { return VP.getPointer(); }
+  Value *getValPtr() const { return V; }
-
-  void setValPtrInt(unsigned K) { VP.setInt(K); }
-  unsigned getValPtrInt() const { return VP.getInt(); }
 
   static bool isValid(Value *V) {
     return V &&
@@ -123,7 +116,7 @@ private:
   HandleBaseKind getKind() const { return PrevPair.getInt(); }
   void setPrevPtr(ValueHandleBase **Ptr) { PrevPair.setPointer(Ptr); }
 
-  /// \brief Add this ValueHandle to the use list for VP.
+  /// \brief Add this ValueHandle to the use list for V.
   ///
   /// List is the address of either the head of the list or a Next node within
   /// the existing use list.
@@ -132,7 +125,7 @@ private:
   /// \brief Add this ValueHandle to the use list after Node.
   void AddToExistingUseListAfter(ValueHandleBase *Node);
 
-  /// \brief Add this ValueHandle to the use list for VP.
+  /// \brief Add this ValueHandle to the use list for V.
   void AddToUseList();
   /// \brief Remove this ValueHandle from its current use list.
   void RemoveFromUseList();

llvm/lib/IR/Value.cpp

@@ -645,7 +645,7 @@ void ValueHandleBase::AddToExistingUseList(ValueHandleBase **List) {
   setPrevPtr(List);
   if (Next) {
     Next->setPrevPtr(&Next);
-    assert(VP.getPointer() == Next->VP.getPointer() && "Added to wrong list?");
+    assert(V == Next->V && "Added to wrong list?");
   }
 }
 
@@ -660,14 +660,14 @@ void ValueHandleBase::AddToExistingUseListAfter(ValueHandleBase *List) {
 }
 
 void ValueHandleBase::AddToUseList() {
-  assert(VP.getPointer() && "Null pointer doesn't have a use list!");
+  assert(V && "Null pointer doesn't have a use list!");
 
-  LLVMContextImpl *pImpl = VP.getPointer()->getContext().pImpl;
+  LLVMContextImpl *pImpl = V->getContext().pImpl;
 
-  if (VP.getPointer()->HasValueHandle) {
+  if (V->HasValueHandle) {
     // If this value already has a ValueHandle, then it must be in the
     // ValueHandles map already.
-    ValueHandleBase *&Entry = pImpl->ValueHandles[VP.getPointer()];
+    ValueHandleBase *&Entry = pImpl->ValueHandles[V];
     assert(Entry && "Value doesn't have any handles?");
     AddToExistingUseList(&Entry);
     return;
@@ -681,10 +681,10 @@ void ValueHandleBase::AddToUseList() {
   DenseMap<Value*, ValueHandleBase*> &Handles = pImpl->ValueHandles;
   const void *OldBucketPtr = Handles.getPointerIntoBucketsArray();
 
-  ValueHandleBase *&Entry = Handles[VP.getPointer()];
+  ValueHandleBase *&Entry = Handles[V];
   assert(!Entry && "Value really did already have handles?");
   AddToExistingUseList(&Entry);
-  VP.getPointer()->HasValueHandle = true;
+  V->HasValueHandle = true;
 
   // If reallocation didn't happen or if this was the first insertion, don't
   // walk the table.
@@ -696,14 +696,14 @@ void ValueHandleBase::AddToUseList() {
   // Okay, reallocation did happen.  Fix the Prev Pointers.
   for (DenseMap<Value*, ValueHandleBase*>::iterator I = Handles.begin(),
        E = Handles.end(); I != E; ++I) {
-    assert(I->second && I->first == I->second->VP.getPointer() &&
+    assert(I->second && I->first == I->second->V &&
            "List invariant broken!");
     I->second->setPrevPtr(&I->second);
   }
 }
 
 void ValueHandleBase::RemoveFromUseList() {
-  assert(VP.getPointer() && VP.getPointer()->HasValueHandle &&
+  assert(V && V->HasValueHandle &&
          "Pointer doesn't have a use list!");
 
   // Unlink this from its use list.
@@ -720,11 +720,11 @@ void ValueHandleBase::RemoveFromUseList() {
   // If the Next pointer was null, then it is possible that this was the last
   // ValueHandle watching VP.  If so, delete its entry from the ValueHandles
   // map.
-  LLVMContextImpl *pImpl = VP.getPointer()->getContext().pImpl;
+  LLVMContextImpl *pImpl = V->getContext().pImpl;
   DenseMap<Value*, ValueHandleBase*> &Handles = pImpl->ValueHandles;
   if (Handles.isPointerIntoBucketsArray(PrevPtr)) {
-    Handles.erase(VP.getPointer());
+    Handles.erase(V);
-    VP.getPointer()->HasValueHandle = false;
+    V->HasValueHandle = false;
   }
 }