Subzero. Fixes memory leaks.

src/IceInst.h

 //===- subzero/src/IceInst.h - High-level instructions ----------*- C++ -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file declares the Inst class and its target-independent
@@ skipping 143 matching lines @@
   }
   virtual void emitIAS(const Cfg *Func) const { emit(Func); }
   virtual void dump(const Cfg *Func) const;
   virtual void dumpExtras(const Cfg *Func) const;
   void dumpDecorated(const Cfg *Func) const;
   void emitSources(const Cfg *Func) const;
   void dumpSources(const Cfg *Func) const;
   void dumpDest(const Cfg *Func) const;
   virtual bool isRedundantAssign() const { return false; }
 
-  virtual ~Inst() {}
-
 protected:
   Inst(Cfg *Func, InstKind Kind, SizeT MaxSrcs, Variable *Dest);
   void addSource(Operand *Src) {
     assert(Src);
     assert(NumSrcs < MaxSrcs);
     Srcs[NumSrcs++] = Src;
   }
   void setLastUse(SizeT VarIndex) {
     if (VarIndex < CHAR_BIT * sizeof(LiveRangesEnded))
       LiveRangesEnded |= (((LREndedBits)1u) << VarIndex);
@@ skipping 46 matching lines @@
 
 protected:
   InstHighLevel(Cfg *Func, InstKind Kind, SizeT MaxSrcs, Variable *Dest)
       : Inst(Func, Kind, MaxSrcs, Dest) {}
   void emit(const Cfg * /*Func*/) const override {
     llvm_unreachable("emit() called on a non-lowered instruction");
   }
   void emitIAS(const Cfg * /*Func*/) const override {
     llvm_unreachable("emitIAS() called on a non-lowered instruction");
   }
-  ~InstHighLevel() override {}
 };
 
 // Alloca instruction.  This captures the size in bytes as getSrc(0),
 // and the required alignment in bytes.  The alignment must be either
 // 0 (no alignment required) or a power of 2.
 class InstAlloca : public InstHighLevel {
   InstAlloca() = delete;
   InstAlloca(const InstAlloca &) = delete;
   InstAlloca &operator=(const InstAlloca &) = delete;
 
 public:
   static InstAlloca *create(Cfg *Func, Operand *ByteCount,
                             uint32_t AlignInBytes, Variable *Dest) {
     return new (Func->allocate<InstAlloca>())
         InstAlloca(Func, ByteCount, AlignInBytes, Dest);
   }
   uint32_t getAlignInBytes() const { return AlignInBytes; }
   Operand *getSizeInBytes() const { return getSrc(0); }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Alloca; }
 
 private:
   InstAlloca(Cfg *Func, Operand *ByteCount, uint32_t AlignInBytes,
              Variable *Dest);
-  ~InstAlloca() override {}
+
   const uint32_t AlignInBytes;
 };
 
 // Binary arithmetic instruction.  The source operands are captured in
 // getSrc(0) and getSrc(1).
 class InstArithmetic : public InstHighLevel {
   InstArithmetic() = delete;
   InstArithmetic(const InstArithmetic &) = delete;
   InstArithmetic &operator=(const InstArithmetic &) = delete;
 
@@ skipping 14 matching lines @@
   static const char *getOpName(OpKind Op);
   bool isCommutative() const;
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) {
     return Inst->getKind() == Arithmetic;
   }
 
 private:
   InstArithmetic(Cfg *Func, OpKind Op, Variable *Dest, Operand *Source1,
                  Operand *Source2);
-  ~InstArithmetic() override {}
 
   const OpKind Op;
 };
 
 // Assignment instruction.  The source operand is captured in
 // getSrc(0).  This is not part of the LLVM bitcode, but is a useful
 // abstraction for some of the lowering.  E.g., if Phi instruction
 // lowering happens before target lowering, or for representing an
 // Inttoptr instruction, or as an intermediate step for lowering a
 // Load instruction.
 class InstAssign : public InstHighLevel {
   InstAssign() = delete;
   InstAssign(const InstAssign &) = delete;
   InstAssign &operator=(const InstAssign &) = delete;
 
 public:
   static InstAssign *create(Cfg *Func, Variable *Dest, Operand *Source) {
     return new (Func->allocate<InstAssign>()) InstAssign(Func, Dest, Source);
   }
   bool isSimpleAssign() const override { return true; }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Assign; }
 
 private:
   InstAssign(Cfg *Func, Variable *Dest, Operand *Source);
-  ~InstAssign() override {}
 };
 
 // Branch instruction.  This represents both conditional and
 // unconditional branches.
 class InstBr : public InstHighLevel {
   InstBr() = delete;
   InstBr(const InstBr &) = delete;
   InstBr &operator=(const InstBr &) = delete;
 
 public:
@@ skipping 23 matching lines @@
   bool isUnconditionalBranch() const override { return isUnconditional(); }
   bool repointEdge(CfgNode *OldNode, CfgNode *NewNode) override;
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Br; }
 
 private:
   // Conditional branch
   InstBr(Cfg *Func, Operand *Source, CfgNode *TargetTrue, CfgNode *TargetFalse);
   // Unconditional branch
   InstBr(Cfg *Func, CfgNode *Target);
-  ~InstBr() override {}
 
   CfgNode *TargetFalse; // Doubles as unconditional branch target
   CfgNode *TargetTrue;  // nullptr if unconditional branch
 };
 
 // Call instruction.  The call target is captured as getSrc(0), and
 // arg I is captured as getSrc(I+1).
 class InstCall : public InstHighLevel {
   InstCall() = delete;
   InstCall(const InstCall &) = delete;
@@ skipping 19 matching lines @@
   static bool classof(const Inst *Inst) { return Inst->getKind() == Call; }
   Type getReturnType() const;
 
 protected:
   InstCall(Cfg *Func, SizeT NumArgs, Variable *Dest, Operand *CallTarget,
            bool HasTailCall, bool HasSideEff, InstKind Kind)
       : InstHighLevel(Func, Kind, NumArgs + 1, Dest), HasTailCall(HasTailCall) {
     HasSideEffects = HasSideEff;
     addSource(CallTarget);
   }
-  ~InstCall() override {}
 
 private:
   bool HasTailCall;
 };
 
 // Cast instruction (a.k.a. conversion operation).
 class InstCast : public InstHighLevel {
   InstCast() = delete;
   InstCast(const InstCast &) = delete;
   InstCast &operator=(const InstCast &) = delete;
@@ skipping 12 matching lines @@
                           Operand *Source) {
     return new (Func->allocate<InstCast>())
         InstCast(Func, CastKind, Dest, Source);
   }
   OpKind getCastKind() const { return CastKind; }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Cast; }
 
 private:
   InstCast(Cfg *Func, OpKind CastKind, Variable *Dest, Operand *Source);
-  ~InstCast() override {}
+
   const OpKind CastKind;
 };
 
 // ExtractElement instruction.
 class InstExtractElement : public InstHighLevel {
   InstExtractElement() = delete;
   InstExtractElement(const InstExtractElement &) = delete;
   InstExtractElement &operator=(const InstExtractElement &) = delete;
 
 public:
   static InstExtractElement *create(Cfg *Func, Variable *Dest, Operand *Source1,
                                     Operand *Source2) {
     return new (Func->allocate<InstExtractElement>())
         InstExtractElement(Func, Dest, Source1, Source2);
   }
 
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) {
     return Inst->getKind() == ExtractElement;
   }
 
 private:
   InstExtractElement(Cfg *Func, Variable *Dest, Operand *Source1,
                      Operand *Source2);
-  ~InstExtractElement() override {}
 };
 
 // Floating-point comparison instruction.  The source operands are
 // captured in getSrc(0) and getSrc(1).
 class InstFcmp : public InstHighLevel {
   InstFcmp() = delete;
   InstFcmp(const InstFcmp &) = delete;
   InstFcmp &operator=(const InstFcmp &) = delete;
 
 public:
   enum FCond {
 #define X(tag, str) tag,
     ICEINSTFCMP_TABLE
 #undef X
         _num
   };
 
   static InstFcmp *create(Cfg *Func, FCond Condition, Variable *Dest,
                           Operand *Source1, Operand *Source2) {
     return new (Func->allocate<InstFcmp>())
         InstFcmp(Func, Condition, Dest, Source1, Source2);
   }
   FCond getCondition() const { return Condition; }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Fcmp; }
 
 private:
   InstFcmp(Cfg *Func, FCond Condition, Variable *Dest, Operand *Source1,
            Operand *Source2);
-  ~InstFcmp() override {}
+
   const FCond Condition;
 };
 
 // Integer comparison instruction.  The source operands are captured
 // in getSrc(0) and getSrc(1).
 class InstIcmp : public InstHighLevel {
   InstIcmp() = delete;
   InstIcmp(const InstIcmp &) = delete;
   InstIcmp &operator=(const InstIcmp &) = delete;
 
@@ skipping 10 matching lines @@
     return new (Func->allocate<InstIcmp>())
         InstIcmp(Func, Condition, Dest, Source1, Source2);
   }
   ICond getCondition() const { return Condition; }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Icmp; }
 
 private:
   InstIcmp(Cfg *Func, ICond Condition, Variable *Dest, Operand *Source1,
            Operand *Source2);
-  ~InstIcmp() override {}
+
   const ICond Condition;
 };
 
 // InsertElement instruction.
 class InstInsertElement : public InstHighLevel {
   InstInsertElement() = delete;
   InstInsertElement(const InstInsertElement &) = delete;
   InstInsertElement &operator=(const InstInsertElement &) = delete;
 
 public:
   static InstInsertElement *create(Cfg *Func, Variable *Dest, Operand *Source1,
                                    Operand *Source2, Operand *Source3) {
     return new (Func->allocate<InstInsertElement>())
         InstInsertElement(Func, Dest, Source1, Source2, Source3);
   }
 
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) {
     return Inst->getKind() == InsertElement;
   }
 
 private:
   InstInsertElement(Cfg *Func, Variable *Dest, Operand *Source1,
                     Operand *Source2, Operand *Source3);
-  ~InstInsertElement() override {}
 };
 
 // Call to an intrinsic function.  The call target is captured as getSrc(0),
 // and arg I is captured as getSrc(I+1).
 class InstIntrinsicCall : public InstCall {
   InstIntrinsicCall() = delete;
   InstIntrinsicCall(const InstIntrinsicCall &) = delete;
   InstIntrinsicCall &operator=(const InstIntrinsicCall &) = delete;
 
 public:
   static InstIntrinsicCall *create(Cfg *Func, SizeT NumArgs, Variable *Dest,
                                    Operand *CallTarget,
                                    const Intrinsics::IntrinsicInfo &Info) {
     return new (Func->allocate<InstIntrinsicCall>())
         InstIntrinsicCall(Func, NumArgs, Dest, CallTarget, Info);
   }
   static bool classof(const Inst *Inst) {
     return Inst->getKind() == IntrinsicCall;
   }
 
   Intrinsics::IntrinsicInfo getIntrinsicInfo() const { return Info; }
 
 private:
   InstIntrinsicCall(Cfg *Func, SizeT NumArgs, Variable *Dest,
                     Operand *CallTarget, const Intrinsics::IntrinsicInfo &Info)
       : InstCall(Func, NumArgs, Dest, CallTarget, false, Info.HasSideEffects,
                  Inst::IntrinsicCall),
         Info(Info) {}
-  ~InstIntrinsicCall() override {}
+
   const Intrinsics::IntrinsicInfo Info;
 };
 
 // Load instruction.  The source address is captured in getSrc(0).
 class InstLoad : public InstHighLevel {
   InstLoad() = delete;
   InstLoad(const InstLoad &) = delete;
   InstLoad &operator=(const InstLoad &) = delete;
 
 public:
   static InstLoad *create(Cfg *Func, Variable *Dest, Operand *SourceAddr,
                           uint32_t Align = 1) {
     // TODO(kschimpf) Stop ignoring alignment specification.
     (void)Align;
     return new (Func->allocate<InstLoad>()) InstLoad(Func, Dest, SourceAddr);
   }
   Operand *getSourceAddress() const { return getSrc(0); }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Load; }
 
 private:
   InstLoad(Cfg *Func, Variable *Dest, Operand *SourceAddr);
-  ~InstLoad() override {}
 };
 
 // Phi instruction.  For incoming edge I, the node is Labels[I] and
 // the Phi source operand is getSrc(I).
 class InstPhi : public InstHighLevel {
   InstPhi() = delete;
   InstPhi(const InstPhi &) = delete;
   InstPhi &operator=(const InstPhi &) = delete;
 
 public:
   static InstPhi *create(Cfg *Func, SizeT MaxSrcs, Variable *Dest) {
     return new (Func->allocate<InstPhi>()) InstPhi(Func, MaxSrcs, Dest);
   }
   void addArgument(Operand *Source, CfgNode *Label);
   Operand *getOperandForTarget(CfgNode *Target) const;
   CfgNode *getLabel(SizeT Index) const { return Labels[Index]; }
   void livenessPhiOperand(LivenessBV &Live, CfgNode *Target,
                           Liveness *Liveness);
   Inst *lower(Cfg *Func);
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Phi; }
 
 private:
   InstPhi(Cfg *Func, SizeT MaxSrcs, Variable *Dest);
   void destroy(Cfg *Func) override {
     Func->deallocateArrayOf<CfgNode *>(Labels);
     Inst::destroy(Func);
   }
-  ~InstPhi() override {}
 
   // Labels[] duplicates the InEdges[] information in the enclosing
   // CfgNode, but the Phi instruction is created before InEdges[]
   // is available, so it's more complicated to share the list.
   CfgNode **Labels;
 };
 
 // Ret instruction.  The return value is captured in getSrc(0), but if
 // there is no return value (void-type function), then
 // getSrcSize()==0 and hasRetValue()==false.
@@ skipping 10 matching lines @@
   Operand *getRetValue() const {
     assert(hasRetValue());
     return getSrc(0);
   }
   NodeList getTerminatorEdges() const override { return NodeList(); }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Ret; }
 
 private:
   InstRet(Cfg *Func, Operand *RetValue);
-  ~InstRet() override {}
 };
 
 // Select instruction.  The condition, true, and false operands are captured.
 class InstSelect : public InstHighLevel {
   InstSelect() = delete;
   InstSelect(const InstSelect &) = delete;
   InstSelect &operator=(const InstSelect &) = delete;
 
 public:
   static InstSelect *create(Cfg *Func, Variable *Dest, Operand *Condition,
                             Operand *SourceTrue, Operand *SourceFalse) {
     return new (Func->allocate<InstSelect>())
         InstSelect(Func, Dest, Condition, SourceTrue, SourceFalse);
   }
   Operand *getCondition() const { return getSrc(0); }
   Operand *getTrueOperand() const { return getSrc(1); }
   Operand *getFalseOperand() const { return getSrc(2); }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Select; }
 
 private:
   InstSelect(Cfg *Func, Variable *Dest, Operand *Condition, Operand *Source1,
              Operand *Source2);
-  ~InstSelect() override {}
 };
 
 // Store instruction.  The address operand is captured, along with the
 // data operand to be stored into the address.
 class InstStore : public InstHighLevel {
   InstStore() = delete;
   InstStore(const InstStore &) = delete;
   InstStore &operator=(const InstStore &) = delete;
 
 public:
   static InstStore *create(Cfg *Func, Operand *Data, Operand *Addr,
                            uint32_t Align = 1) {
     // TODO(kschimpf) Stop ignoring alignment specification.
     (void)Align;
     return new (Func->allocate<InstStore>()) InstStore(Func, Data, Addr);
   }
   Operand *getAddr() const { return getSrc(1); }
   Operand *getData() const { return getSrc(0); }
   Variable *getRmwBeacon() const { return llvm::dyn_cast<Variable>(getSrc(2)); }
   void setRmwBeacon(Variable *Beacon);
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Store; }
 
 private:
   InstStore(Cfg *Func, Operand *Data, Operand *Addr);
-  ~InstStore() override {}
 };
 
 // Switch instruction.  The single source operand is captured as
 // getSrc(0).
 class InstSwitch : public InstHighLevel {
   InstSwitch() = delete;
   InstSwitch(const InstSwitch &) = delete;
   InstSwitch &operator=(const InstSwitch &) = delete;
 
 public:
@@ skipping 19 matching lines @@
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == Switch; }
 
 private:
   InstSwitch(Cfg *Func, SizeT NumCases, Operand *Source, CfgNode *LabelDefault);
   void destroy(Cfg *Func) override {
     Func->deallocateArrayOf<uint64_t>(Values);
     Func->deallocateArrayOf<CfgNode *>(Labels);
     Inst::destroy(Func);
   }
-  ~InstSwitch() override {}
 
   CfgNode *LabelDefault;
   SizeT NumCases;   // not including the default case
   uint64_t *Values; // size is NumCases
   CfgNode **Labels; // size is NumCases
 };
 
 // Unreachable instruction.  This is a terminator instruction with no
 // operands.
 class InstUnreachable : public InstHighLevel {
   InstUnreachable() = delete;
   InstUnreachable(const InstUnreachable &) = delete;
   InstUnreachable &operator=(const InstUnreachable &) = delete;
 
 public:
   static InstUnreachable *create(Cfg *Func) {
     return new (Func->allocate<InstUnreachable>()) InstUnreachable(Func);
   }
   NodeList getTerminatorEdges() const override { return NodeList(); }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) {
     return Inst->getKind() == Unreachable;
   }
 
 private:
   explicit InstUnreachable(Cfg *Func);
-  ~InstUnreachable() override {}
 };
 
 // BundleLock instruction.  There are no operands.  Contains an option
 // indicating whether align_to_end is specified.
 class InstBundleLock : public InstHighLevel {
   InstBundleLock() = delete;
   InstBundleLock(const InstBundleLock &) = delete;
   InstBundleLock &operator=(const InstBundleLock &) = delete;
 
 public:
   enum Option { Opt_None, Opt_AlignToEnd };
   static InstBundleLock *create(Cfg *Func, Option BundleOption) {
     return new (Func->allocate<InstBundleLock>())
         InstBundleLock(Func, BundleOption);
   }
   void emit(const Cfg *Func) const override;
   void emitIAS(const Cfg * /* Func */) const override {}
   void dump(const Cfg *Func) const override;
   Option getOption() const { return BundleOption; }
   static bool classof(const Inst *Inst) {
     return Inst->getKind() == BundleLock;
   }
 
 private:
   Option BundleOption;
   InstBundleLock(Cfg *Func, Option BundleOption);
-  ~InstBundleLock() override {}
 };
 
 // BundleUnlock instruction.  There are no operands.
 class InstBundleUnlock : public InstHighLevel {
   InstBundleUnlock() = delete;
   InstBundleUnlock(const InstBundleUnlock &) = delete;
   InstBundleUnlock &operator=(const InstBundleUnlock &) = delete;
 
 public:
   static InstBundleUnlock *create(Cfg *Func) {
     return new (Func->allocate<InstBundleUnlock>()) InstBundleUnlock(Func);
   }
   void emit(const Cfg *Func) const override;
   void emitIAS(const Cfg * /* Func */) const override {}
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) {
     return Inst->getKind() == BundleUnlock;
   }
 
 private:
   explicit InstBundleUnlock(Cfg *Func);
-  ~InstBundleUnlock() override {}
 };
 
 // FakeDef instruction.  This creates a fake definition of a variable,
 // which is how we represent the case when an instruction produces
 // multiple results.  This doesn't happen with high-level ICE
 // instructions, but might with lowered instructions.  For example,
 // this would be a way to represent condition flags being modified by
 // an instruction.
 //
 // It's generally useful to set the optional source operand to be the
@@ skipping 11 matching lines @@
                              Variable *Src = nullptr) {
     return new (Func->allocate<InstFakeDef>()) InstFakeDef(Func, Dest, Src);
   }
   void emit(const Cfg *Func) const override;
   void emitIAS(const Cfg * /* Func */) const override {}
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == FakeDef; }
 
 private:
   InstFakeDef(Cfg *Func, Variable *Dest, Variable *Src);
-  ~InstFakeDef() override {}
 };
 
 // FakeUse instruction.  This creates a fake use of a variable, to
 // keep the instruction that produces that variable from being
 // dead-code eliminated.  This is useful in a variety of lowering
 // situations.  The FakeUse instruction has no dest, so it can itself
 // never be dead-code eliminated.
 class InstFakeUse : public InstHighLevel {
   InstFakeUse() = delete;
   InstFakeUse(const InstFakeUse &) = delete;
   InstFakeUse &operator=(const InstFakeUse &) = delete;
 
 public:
   static InstFakeUse *create(Cfg *Func, Variable *Src) {
     return new (Func->allocate<InstFakeUse>()) InstFakeUse(Func, Src);
   }
   void emit(const Cfg *Func) const override;
   void emitIAS(const Cfg * /* Func */) const override {}
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == FakeUse; }
 
 private:
   InstFakeUse(Cfg *Func, Variable *Src);
-  ~InstFakeUse() override {}
 };
 
 // FakeKill instruction.  This "kills" a set of variables by modeling
 // a trivial live range at this instruction for each (implicit)
 // variable.  The primary use is to indicate that scratch registers
 // are killed after a call, so that the register allocator won't
 // assign a scratch register to a variable whose live range spans a
 // call.
 //
 // The FakeKill instruction also holds a pointer to the instruction
 // that kills the set of variables, so that if that linked instruction
 // gets dead-code eliminated, the FakeKill instruction will as well.
 class InstFakeKill : public InstHighLevel {
   InstFakeKill() = delete;
   InstFakeKill(const InstFakeKill &) = delete;
   InstFakeKill &operator=(const InstFakeKill &) = delete;
 
 public:
   static InstFakeKill *create(Cfg *Func, const Inst *Linked) {
     return new (Func->allocate<InstFakeKill>()) InstFakeKill(Func, Linked);
   }
   const Inst *getLinked() const { return Linked; }
   void emit(const Cfg *Func) const override;
   void emitIAS(const Cfg * /* Func */) const override {}
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() == FakeKill; }
 
 private:
   InstFakeKill(Cfg *Func, const Inst *Linked);
-  ~InstFakeKill() override {}
 
   // This instruction is ignored if Linked->isDeleted() is true.
   const Inst *Linked;
 };
 
 // The Target instruction is the base class for all target-specific
 // instructions.
 class InstTarget : public Inst {
   InstTarget() = delete;
   InstTarget(const InstTarget &) = delete;
   InstTarget &operator=(const InstTarget &) = delete;
 
 public:
   uint32_t getEmitInstCount() const override { return 1; }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Inst) { return Inst->getKind() >= Target; }
 
 protected:
   InstTarget(Cfg *Func, InstKind Kind, SizeT MaxSrcs, Variable *Dest)
       : Inst(Func, Kind, MaxSrcs, Dest) {
     assert(Kind >= Target);
   }
-  ~InstTarget() override {}
 };
 
 bool checkForRedundantAssign(const Variable *Dest, const Operand *Source);
 
 } // end of namespace Ice
 
 namespace llvm {
 
 // Override the default ilist traits so that Inst's private ctor and
 // deleted dtor aren't invoked.
 template <>
 struct ilist_traits<Ice::Inst> : public ilist_default_traits<Ice::Inst> {
   Ice::Inst *createSentinel() const {
     return static_cast<Ice::Inst *>(&Sentinel);
   }
   static void destroySentinel(Ice::Inst *) {}
   Ice::Inst *provideInitialHead() const { return createSentinel(); }
   Ice::Inst *ensureHead(Ice::Inst *) const { return createSentinel(); }
   static void noteHead(Ice::Inst *, Ice::Inst *) {}
   void deleteNode(Ice::Inst *) {}
 
 private:
   mutable ilist_half_node<Ice::Inst> Sentinel;
 };
 
 } // end of namespace llvm
 
 #endif // SUBZERO_SRC_ICEINST_H