[IR] Added operator delete to subclasses of User to avoid UB

[MoritzS]

Summary

Several subclasses of User override operator new without also overriding
operator delete. This means that delete expressions fall back to using
operator delete of the base class, which would be User. However, this is
only allowed if the base class has a virtual destructor which is not the
case for User, so this is UB.

See also [expr.delete] (3) for the exact wording.

This is actually detected in some cases by GCC 11's
-Wmismatched-new-delete now which is how I found this error.

[MoritzS]

Rebased onto main

[dblaikie]

Sounds OK to me - might not hurt to fix the naming convention issues on the lines you're touching/adding.

[MoritzS]

Fixed variable names

[MoritzS]

User::operator delete(Ptr) must not be called with any additional arguments. Fixed that.

llvm/include/llvm/Analysis/MemorySSA.h

 public:
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(MemoryAccess);
 
   MemoryUse(LLVMContext &C, MemoryAccess *DMA, Instruction *MI, BasicBlock *BB)
       : MemoryUseOrDef(C, DMA, MemoryUseVal, deleteMe, MI, BB,
                        /*NumOperands=*/1) {}
 
   // allocate space for exactly one operand
-  void *operator new(size_t s) { return User::operator new(s, 1); }
+  void *operator new(size_t S) { return User::operator new(S, 1); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   static bool classof(const Value *MA) {
     return MA->getValueID() == MemoryUseVal;
   }
 
   void print(raw_ostream &OS) const;
 
   void setOptimized(MemoryAccess *DMA) {
public:
 
   MemoryDef(LLVMContext &C, MemoryAccess *DMA, Instruction *MI, BasicBlock *BB,
             unsigned Ver)
       : MemoryUseOrDef(C, DMA, MemoryDefVal, deleteMe, MI, BB,
                        /*NumOperands=*/2),
         ID(Ver) {}
 
   // allocate space for exactly two operands
-  void *operator new(size_t s) { return User::operator new(s, 2); }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   static bool classof(const Value *MA) {
     return MA->getValueID() == MemoryDefVal;
   }
 
   void setOptimized(MemoryAccess *MA) {
     setOperand(1, MA);
     OptimizedID = MA->getID();

 /// }
 /// even if the two stores do not conflict. Otherwise, both 1 and 2 reach the
 /// end of the branch, and if there are not two phi nodes, one will be
 /// disconnected completely from the SSA graph below that point.
 /// Because MemoryUse's do not generate new definitions, they do not have this
 /// issue.
 class MemoryPhi final : public MemoryAccess {
   // allocate space for exactly zero operands
-  void *operator new(size_t s) { return User::operator new(s); }
+  void *operator new(size_t S) { return User::operator new(S); }
 
 public:
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
+
   /// Provide fast operand accessors
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(MemoryAccess);
 
   MemoryPhi(LLVMContext &C, BasicBlock *BB, unsigned Ver, unsigned NumPreds = 0)
       : MemoryAccess(C, MemoryPhiVal, deleteMe, BB, 0), ID(Ver),
         ReservedSpace(NumPreds) {
     allocHungoffUses(ReservedSpace);
   }

llvm/include/llvm/IR/Constants.h

class ConstantData : public Constant {
 
   Value *handleOperandChangeImpl(Value *From, Value *To) {
     llvm_unreachable("Constant data does not have operands!");
   }
 
 protected:
   explicit ConstantData(Type *Ty, ValueTy VT) : Constant(Ty, VT, nullptr, 0) {}
 
-  void *operator new(size_t s) { return User::operator new(s, 0); }
+  void *operator new(size_t S) { return User::operator new(S, 0); }
 
 public:
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
+
   ConstantData(const ConstantData &) = delete;
 
   /// Methods to support type inquiry through isa, cast, and dyn_cast.
   static bool classof(const Value *V) {
     return V->getValueID() >= ConstantDataFirstVal &&
            V->getValueID() <= ConstantDataLastVal;
   }
 };

 
 /// The address of a basic block.
 ///
 class BlockAddress final : public Constant {
   friend class Constant;
 
   BlockAddress(Function *F, BasicBlock *BB);
 
-  void *operator new(size_t s) { return User::operator new(s, 2); }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
 
   void destroyConstantImpl();
   Value *handleOperandChangeImpl(Value *From, Value *To);
 
 public:
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
+
   /// Return a BlockAddress for the specified function and basic block.
   static BlockAddress *get(Function *F, BasicBlock *BB);
 
   /// Return a BlockAddress for the specified basic block.  The basic
   /// block must be embedded into a function.
   static BlockAddress *get(BasicBlock *BB);
 
   /// Lookup an existing \c BlockAddress constant for the given BasicBlock.

 /// Wrapper for a function that represents a value that
 /// functionally represents the original function. This can be a function,
 /// global alias to a function, or an ifunc.
 class DSOLocalEquivalent final : public Constant {
   friend class Constant;
 
   DSOLocalEquivalent(GlobalValue *GV);
 
-  void *operator new(size_t s) { return User::operator new(s, 1); }
+  void *operator new(size_t S) { return User::operator new(S, 1); }
 
   void destroyConstantImpl();
   Value *handleOperandChangeImpl(Value *From, Value *To);
 
 public:
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
+
   /// Return a DSOLocalEquivalent for the specified global value.
   static DSOLocalEquivalent *get(GlobalValue *GV);
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   GlobalValue *getGlobalValue() const {
     return cast<GlobalValue>(Op<0>().get());

llvm/include/llvm/IR/GlobalIndirectSymbol.h

protected:
   GlobalIndirectSymbol(Type *Ty, ValueTy VTy, unsigned AddressSpace,
       LinkageTypes Linkage, const Twine &Name, Constant *Symbol);
 
 public:
   GlobalIndirectSymbol(const GlobalIndirectSymbol &) = delete;
   GlobalIndirectSymbol &operator=(const GlobalIndirectSymbol &) = delete;
 
   // allocate space for exactly one operand
-  void *operator new(size_t s) {
-    return User::operator new(s, 1);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 1); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   /// Provide fast operand accessors
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Constant);
 
   void copyAttributesFrom(const GlobalValue *Src) {
     GlobalValue::copyAttributesFrom(Src);
   }
 

llvm/include/llvm/IR/InstrTypes.h

protected:
   }
   UnaryInstruction(Type *Ty, unsigned iType, Value *V, BasicBlock *IAE)
     : Instruction(Ty, iType, &Op<0>(), 1, IAE) {
     Op<0>() = V;
   }
 
 public:
   // allocate space for exactly one operand
-  void *operator new(size_t s) {
-    return User::operator new(s, 1);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 1); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->isUnaryOp() ||
            I->getOpcode() == Instruction::Alloca ||
protected:
 
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   BinaryOperator *cloneImpl() const;
 
 public:
   // allocate space for exactly two operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 2);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   /// Construct a binary instruction, given the opcode and the two
   /// operands.  Optionally (if InstBefore is specified) insert the instruction
   /// into a BasicBlock right before the specified instruction.  The specified
   /// Instruction is allowed to be a dereferenced end iterator.
CmpInst(Type *ty, Instruction::OtherOps op, Predicate pred,
           Instruction *FlagsSource = nullptr);
 
   CmpInst(Type *ty, Instruction::OtherOps op, Predicate pred,
           Value *LHS, Value *RHS, const Twine &Name,
           BasicBlock *InsertAtEnd);
 
 public:
   // allocate space for exactly two operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 2);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   /// Construct a compare instruction, given the opcode, the predicate and
   /// the two operands.  Optionally (if InstBefore is specified) insert the
   /// instruction into a BasicBlock right before the specified instruction.
   /// The specified Instruction is allowed to be a dereferenced end iterator.
   /// Create a CmpInst
   static CmpInst *Create(OtherOps Op,
                          Predicate predicate, Value *S1,

llvm/include/llvm/IR/Instructions.h

StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
             BasicBlock *InsertAtEnd);
   StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
             AtomicOrdering Order, SyncScope::ID SSID = SyncScope::System,
             Instruction *InsertBefore = nullptr);
   StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
             AtomicOrdering Order, SyncScope::ID SSID, BasicBlock *InsertAtEnd);
 
   // allocate space for exactly two operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 2);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   /// Return true if this is a store to a volatile memory location.
   bool isVolatile() const { return getSubclassData<VolatileField>(); }
 
   /// Specify whether this is a volatile store or not.
   void setVolatile(bool V) { setSubclassData<VolatileField>(V); }
 
   /// Transparently provide more efficient getOperand methods.
public:
   // SequentiallyConsistent.
   FenceInst(LLVMContext &C, AtomicOrdering Ordering,
             SyncScope::ID SSID = SyncScope::System,
             Instruction *InsertBefore = nullptr);
   FenceInst(LLVMContext &C, AtomicOrdering Ordering, SyncScope::ID SSID,
             BasicBlock *InsertAtEnd);
 
   // allocate space for exactly zero operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 0);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 0); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   /// Returns the ordering constraint of this fence instruction.
   AtomicOrdering getOrdering() const {
     return getSubclassData<OrderingField>();
   }
 
   /// Sets the ordering constraint of this fence instruction.  May only be
   /// Acquire, Release, AcquireRelease, or SequentiallyConsistent.
AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal, Align Alignment,
                     AtomicOrdering FailureOrdering, SyncScope::ID SSID,
                     Instruction *InsertBefore = nullptr);
   AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal, Align Alignment,
                     AtomicOrdering SuccessOrdering,
                     AtomicOrdering FailureOrdering, SyncScope::ID SSID,
                     BasicBlock *InsertAtEnd);
 
   // allocate space for exactly three operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 3);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 3); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   using VolatileField = BoolBitfieldElementT<0>;
   using WeakField = BoolBitfieldElementT<VolatileField::NextBit>;
   using SuccessOrderingField =
       AtomicOrderingBitfieldElementT<WeakField::NextBit>;
   using FailureOrderingField =
       AtomicOrderingBitfieldElementT<SuccessOrderingField::NextBit>;
   using AlignmentField =
public:
   AtomicRMWInst(BinOp Operation, Value *Ptr, Value *Val, Align Alignment,
                 AtomicOrdering Ordering, SyncScope::ID SSID,
                 Instruction *InsertBefore = nullptr);
   AtomicRMWInst(BinOp Operation, Value *Ptr, Value *Val, Align Alignment,
                 AtomicOrdering Ordering, SyncScope::ID SSID,
                 BasicBlock *InsertAtEnd);
 
   // allocate space for exactly two operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 2);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   using VolatileField = BoolBitfieldElementT<0>;
   using AtomicOrderingField =
       AtomicOrderingBitfieldElementT<VolatileField::NextBit>;
   using OperationField = BinOpBitfieldElement<AtomicOrderingField::NextBit>;
   using AlignmentField = AlignmentBitfieldElementT<OperationField::NextBit>;
   static_assert(Bitfield::areContiguous<VolatileField, AtomicOrderingField,
                                         OperationField, AlignmentField>(),
public:
   ShuffleVectorInst(Value *V1, Value *V2, Value *Mask,
                     const Twine &NameStr, BasicBlock *InsertAtEnd);
   ShuffleVectorInst(Value *V1, Value *V2, ArrayRef<int> Mask,
                     const Twine &NameStr = "",
                     Instruction *InsertBefor = nullptr);
   ShuffleVectorInst(Value *V1, Value *V2, ArrayRef<int> Mask,
                     const Twine &NameStr, BasicBlock *InsertAtEnd);
 
-  void *operator new(size_t s) { return User::operator new(s, 2); }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
+  void operator delete(void *Ptr) { return User::operator delete(Ptr); }
 
   /// Swap the operands and adjust the mask to preserve the semantics
   /// of the instruction.
   void commute();
 
   /// Return true if a shufflevector instruction can be
   /// formed with the specified operands.
   static bool isValidOperands(const Value *V1, const Value *V2,

 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   InsertValueInst *cloneImpl() const;
 
 public:
   // allocate space for exactly two operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 2);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   static InsertValueInst *Create(Value *Agg, Value *Val,
                                  ArrayRef<unsigned> Idxs,
                                  const Twine &NameStr = "",
                                  Instruction *InsertBefore = nullptr) {
     return new InsertValueInst(Agg, Val, Idxs, NameStr, InsertBefore);
   }
 

 
 private:
   explicit LandingPadInst(Type *RetTy, unsigned NumReservedValues,
                           const Twine &NameStr, Instruction *InsertBefore);
   explicit LandingPadInst(Type *RetTy, unsigned NumReservedValues,
                           const Twine &NameStr, BasicBlock *InsertAtEnd);
 
   // Allocate space for exactly zero operands.
-  void *operator new(size_t s) {
-    return User::operator new(s);
-  }
+  void *operator new(size_t S) { return User::operator new(S); }
 
   void growOperands(unsigned Size);
   void init(unsigned NumReservedValues, const Twine &NameStr);
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   LandingPadInst *cloneImpl() const;
 
 public:
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
+
   /// Constructors - NumReservedClauses is a hint for the number of incoming
   /// clauses that this landingpad will have (use 0 if you really have no idea).
   static LandingPadInst *Create(Type *RetTy, unsigned NumReservedClauses,
                                 const Twine &NameStr = "",
                                 Instruction *InsertBefore = nullptr);
   static LandingPadInst *Create(Type *RetTy, unsigned NumReservedClauses,
                                 const Twine &NameStr, BasicBlock *InsertAtEnd);
 
class SwitchInst : public Instruction {
   /// Create a new switch instruction, specifying a value to switch on and a
   /// default destination. The number of additional cases can be specified here
   /// to make memory allocation more efficient. This constructor also
   /// auto-inserts at the end of the specified BasicBlock.
   SwitchInst(Value *Value, BasicBlock *Default, unsigned NumCases,
              BasicBlock *InsertAtEnd);
 
   // allocate space for exactly zero operands
-  void *operator new(size_t s) {
-    return User::operator new(s);
-  }
+  void *operator new(size_t S) { return User::operator new(S); }
 
   void init(Value *Value, BasicBlock *Default, unsigned NumReserved);
   void growOperands();
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   SwitchInst *cloneImpl() const;
 
 public:
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
+
   // -2
   static const unsigned DefaultPseudoIndex = static_cast<unsigned>(~0L-1);
 
   template <typename CaseHandleT> class CaseIteratorImpl;
 
   /// A handle to a particular switch case. It exposes a convenient interface
   /// to both the case value and the successor block.
   ///
class IndirectBrInst : public Instruction {
 
   /// Create a new indirectbr instruction, specifying an
   /// Address to jump to.  The number of expected destinations can be specified
   /// here to make memory allocation more efficient.  This constructor also
   /// autoinserts at the end of the specified BasicBlock.
   IndirectBrInst(Value *Address, unsigned NumDests, BasicBlock *InsertAtEnd);
 
   // allocate space for exactly zero operands
-  void *operator new(size_t s) {
-    return User::operator new(s);
-  }
+  void *operator new(size_t S) { return User::operator new(S); }
 
   void init(Value *Address, unsigned NumDests);
   void growOperands();
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   IndirectBrInst *cloneImpl() const;
 
 public:
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
+
   /// Iterator type that casts an operand to a basic block.
   ///
   /// This only makes sense because the successors are stored as adjacent
   /// operands for indirectbr instructions.
   struct succ_op_iterator
       : iterator_adaptor_base<succ_op_iterator, value_op_iterator,
                               std::random_access_iterator_tag, BasicBlock *,
                               ptrdiff_t, BasicBlock *, BasicBlock *> {
class CatchSwitchInst : public Instruction {
   /// default destination.  The number of additional handlers can be specified
   /// here to make memory allocation more efficient.
   /// This constructor also autoinserts at the end of the specified BasicBlock.
   CatchSwitchInst(Value *ParentPad, BasicBlock *UnwindDest,
                   unsigned NumHandlers, const Twine &NameStr,
                   BasicBlock *InsertAtEnd);
 
   // allocate space for exactly zero operands
-  void *operator new(size_t s) { return User::operator new(s); }
+  void *operator new(size_t S) { return User::operator new(S); }
 
   void init(Value *ParentPad, BasicBlock *UnwindDest, unsigned NumReserved);
   void growOperands(unsigned Size);
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   CatchSwitchInst *cloneImpl() const;
 
 public:
+  void operator delete(void *Ptr) { return User::operator delete(Ptr); }
+
   static CatchSwitchInst *Create(Value *ParentPad, BasicBlock *UnwindDest,
                                  unsigned NumHandlers,
                                  const Twine &NameStr = "",
                                  Instruction *InsertBefore = nullptr) {
     return new CatchSwitchInst(ParentPad, UnwindDest, NumHandlers, NameStr,
                                InsertBefore);
   }
 
protected:
 
   UnreachableInst *cloneImpl() const;
 
 public:
   explicit UnreachableInst(LLVMContext &C, Instruction *InsertBefore = nullptr);
   explicit UnreachableInst(LLVMContext &C, BasicBlock *InsertAtEnd);
 
   // allocate space for exactly zero operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 0);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 0); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   unsigned getNumSuccessors() const { return 0; }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::Unreachable;
   }
   static bool classof(const Value *V) {

llvm/lib/IR/ConstantsContext.h

 class UnaryConstantExpr final : public ConstantExpr {
 public:
   UnaryConstantExpr(unsigned Opcode, Constant *C, Type *Ty)
     : ConstantExpr(Ty, Opcode, &Op<0>(), 1) {
     Op<0>() = C;
   }
 
   // allocate space for exactly one operand
-  void *operator new(size_t s) {
-    return User::operator new(s, 1);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 1); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   static bool classof(const ConstantExpr *CE) {
     return Instruction::isCast(CE->getOpcode()) ||
            Instruction::isUnaryOp(CE->getOpcode());
   }
   static bool classof(const Value *V) {
BinaryConstantExpr(unsigned Opcode, Constant *C1, Constant *C2,
                      unsigned Flags)
     : ConstantExpr(C1->getType(), Opcode, &Op<0>(), 2) {
     Op<0>() = C1;
     Op<1>() = C2;
     SubclassOptionalData = Flags;
   }
 
   // allocate space for exactly two operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 2);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   static bool classof(const ConstantExpr *CE) {
     return Instruction::isBinaryOp(CE->getOpcode());
   }
   static bool classof(const Value *V) {
     return isa<ConstantExpr>(V) && classof(cast<ConstantExpr>(V));
   }
 };
 
 /// SelectConstantExpr - This class is private to Constants.cpp, and is used
 /// behind the scenes to implement select constant exprs.
 class SelectConstantExpr final : public ConstantExpr {
 public:
   SelectConstantExpr(Constant *C1, Constant *C2, Constant *C3)
     : ConstantExpr(C2->getType(), Instruction::Select, &Op<0>(), 3) {
     Op<0>() = C1;
     Op<1>() = C2;
     Op<2>() = C3;
   }
 
   // allocate space for exactly three operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 3);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 3); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   static bool classof(const ConstantExpr *CE) {
     return CE->getOpcode() == Instruction::Select;
   }
   static bool classof(const Value *V) {
public:
   ExtractElementConstantExpr(Constant *C1, Constant *C2)
     : ConstantExpr(cast<VectorType>(C1->getType())->getElementType(),
                    Instruction::ExtractElement, &Op<0>(), 2) {
     Op<0>() = C1;
     Op<1>() = C2;
   }
 
   // allocate space for exactly two operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 2);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   static bool classof(const ConstantExpr *CE) {
     return CE->getOpcode() == Instruction::ExtractElement;
   }
   static bool classof(const Value *V) {
InsertElementConstantExpr(Constant *C1, Constant *C2, Constant *C3)
     : ConstantExpr(C1->getType(), Instruction::InsertElement,
                    &Op<0>(), 3) {
     Op<0>() = C1;
     Op<1>() = C2;
     Op<2>() = C3;
   }
 
   // allocate space for exactly three operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 3);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 3); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   static bool classof(const ConstantExpr *CE) {
     return CE->getOpcode() == Instruction::InsertElement;
   }
   static bool classof(const Value *V) {
ShuffleVectorConstantExpr(Constant *C1, Constant *C2, ArrayRef<int> Mask)
     ShuffleMask.assign(Mask.begin(), Mask.end());
     ShuffleMaskForBitcode =
         ShuffleVectorInst::convertShuffleMaskForBitcode(Mask, getType());
   }
 
   SmallVector<int, 4> ShuffleMask;
   Constant *ShuffleMaskForBitcode;
 
-  void *operator new(size_t s) { return User::operator new(s, 2); }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
+  void operator delete(void *Ptr) { return User::operator delete(Ptr); }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   static bool classof(const ConstantExpr *CE) {
     return CE->getOpcode() == Instruction::ShuffleVector;
   }
   static bool classof(const Value *V) {
public:
   ExtractValueConstantExpr(Constant *Agg, ArrayRef<unsigned> IdxList,
                            Type *DestTy)
       : ConstantExpr(DestTy, Instruction::ExtractValue, &Op<0>(), 1),
         Indices(IdxList.begin(), IdxList.end()) {
     Op<0>() = Agg;
   }
 
   // allocate space for exactly one operand
-  void *operator new(size_t s) {
-    return User::operator new(s, 1);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 1); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   /// Indices - These identify which value to extract.
   const SmallVector<unsigned, 4> Indices;
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   static bool classof(const ConstantExpr *CE) {
InsertValueConstantExpr(Constant *Agg, Constant *Val,
                           ArrayRef<unsigned> IdxList, Type *DestTy)
       : ConstantExpr(DestTy, Instruction::InsertValue, &Op<0>(), 2),
         Indices(IdxList.begin(), IdxList.end()) {
     Op<0>() = Agg;
     Op<1>() = Val;
   }
 
   // allocate space for exactly one operand
-  void *operator new(size_t s) {
-    return User::operator new(s, 2);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
+  void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   /// Indices - These identify the position for the insertion.
   const SmallVector<unsigned, 4> Indices;
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   static bool classof(const ConstantExpr *CE) {
public:
   CompareConstantExpr(Type *ty, Instruction::OtherOps opc,
                       unsigned short pred,  Constant* LHS, Constant* RHS)
     : ConstantExpr(ty, opc, &Op<0>(), 2), predicate(pred) {
     Op<0>() = LHS;
     Op<1>() = RHS;
   }
 
   // allocate space for exactly two operands
-  void *operator new(size_t s) {
-    return User::operator new(s, 2);
-  }
+  void *operator new(size_t S) { return User::operator new(S, 2); }
+  void operator delete(void *Ptr) { return User::operator delete(Ptr); }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   static bool classof(const ConstantExpr *CE) {
     return CE->getOpcode() == Instruction::ICmp ||
            CE->getOpcode() == Instruction::FCmp;
   }