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 //===- llvm/Instructions.h - Instruction subclass definitions ---*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file exposes the class definitions of all of the subclasses of the
 // Instruction class.  This is meant to be an easy way to get access to all
 // instruction subclasses.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_IR_INSTRUCTIONS_H
 #define LLVM_IR_INSTRUCTIONS_H
 
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/Bitfields.h"
 #include "llvm/ADT/MapVector.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/Twine.h"
 #include "llvm/ADT/iterator.h"
 #include "llvm/ADT/iterator_range.h"
 #include "llvm/IR/CFG.h"
 #include "llvm/IR/CmpPredicate.h"
 #include "llvm/IR/Constant.h"
 #include "llvm/IR/DerivedTypes.h"
 #include "llvm/IR/GEPNoWrapFlags.h"
 #include "llvm/IR/InstrTypes.h"
 #include "llvm/IR/Instruction.h"
 #include "llvm/IR/Intrinsics.h"
 #include "llvm/IR/OperandTraits.h"
 #include "llvm/IR/Use.h"
 #include "llvm/IR/User.h"
 #include "llvm/Support/AtomicOrdering.h"
 #include "llvm/Support/ErrorHandling.h"
 #include <cassert>
 #include <cstddef>
 #include <cstdint>
 #include <iterator>
 #include <optional>
 
 namespace llvm {
 
 class APFloat;
 class APInt;
 class BasicBlock;
 class ConstantInt;
 class DataLayout;
 struct KnownBits;
 class StringRef;
 class Type;
 class Value;
 class UnreachableInst;
 
 //===----------------------------------------------------------------------===//
 //                                AllocaInst Class
 //===----------------------------------------------------------------------===//
 
 /// an instruction to allocate memory on the stack
 class AllocaInst : public UnaryInstruction {
   Type *AllocatedType;
 
   using AlignmentField = AlignmentBitfieldElementT<0>;
   using UsedWithInAllocaField = BoolBitfieldElementT<AlignmentField::NextBit>;
   using SwiftErrorField = BoolBitfieldElementT<UsedWithInAllocaField::NextBit>;
   static_assert(Bitfield::areContiguous<AlignmentField, UsedWithInAllocaField,
                                         SwiftErrorField>(),
                 "Bitfields must be contiguous");
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   AllocaInst *cloneImpl() const;
 
 public:
   explicit AllocaInst(Type *Ty, unsigned AddrSpace, Value *ArraySize,
                       const Twine &Name, InsertPosition InsertBefore);
 
   AllocaInst(Type *Ty, unsigned AddrSpace, const Twine &Name,
              InsertPosition InsertBefore);
 
   AllocaInst(Type *Ty, unsigned AddrSpace, Value *ArraySize, Align Align,
              const Twine &Name = "", InsertPosition InsertBefore = nullptr);
 
   /// Return true if there is an allocation size parameter to the allocation
   /// instruction that is not 1.
   bool isArrayAllocation() const;
 
   /// Get the number of elements allocated. For a simple allocation of a single
   /// element, this will return a constant 1 value.
   const Value *getArraySize() const { return getOperand(0); }
   Value *getArraySize() { return getOperand(0); }
 
   /// Overload to return most specific pointer type.
   PointerType *getType() const {
     return cast<PointerType>(Instruction::getType());
   }
 
   /// Return the address space for the allocation.
   unsigned getAddressSpace() const {
     return getType()->getAddressSpace();
   }
 
   /// Get allocation size in bytes. Returns std::nullopt if size can't be
   /// determined, e.g. in case of a VLA.
   std::optional<TypeSize> getAllocationSize(const DataLayout &DL) const;
 
   /// Get allocation size in bits. Returns std::nullopt if size can't be
   /// determined, e.g. in case of a VLA.
   std::optional<TypeSize> getAllocationSizeInBits(const DataLayout &DL) const;
 
   /// Return the type that is being allocated by the instruction.
   Type *getAllocatedType() const { return AllocatedType; }
   /// for use only in special circumstances that need to generically
   /// transform a whole instruction (eg: IR linking and vectorization).
   void setAllocatedType(Type *Ty) { AllocatedType = Ty; }
 
   /// Return the alignment of the memory that is being allocated by the
   /// instruction.
   Align getAlign() const {
     return Align(1ULL << getSubclassData<AlignmentField>());
   }
 
   void setAlignment(Align Align) {
     setSubclassData<AlignmentField>(Log2(Align));
   }
 
   /// Return true if this alloca is in the entry block of the function and is a
   /// constant size. If so, the code generator will fold it into the
   /// prolog/epilog code, so it is basically free.
   bool isStaticAlloca() const;
 
   /// Return true if this alloca is used as an inalloca argument to a call. Such
   /// allocas are never considered static even if they are in the entry block.
   bool isUsedWithInAlloca() const {
     return getSubclassData<UsedWithInAllocaField>();
   }
 
   /// Specify whether this alloca is used to represent the arguments to a call.
   void setUsedWithInAlloca(bool V) {
     setSubclassData<UsedWithInAllocaField>(V);
   }
 
   /// Return true if this alloca is used as a swifterror argument to a call.
   bool isSwiftError() const { return getSubclassData<SwiftErrorField>(); }
   /// Specify whether this alloca is used to represent a swifterror.
   void setSwiftError(bool V) { setSubclassData<SwiftErrorField>(V); }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return (I->getOpcode() == Instruction::Alloca);
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   // Shadow Instruction::setInstructionSubclassData with a private forwarding
   // method so that subclasses cannot accidentally use it.
   template <typename Bitfield>
   void setSubclassData(typename Bitfield::Type Value) {
     Instruction::setSubclassData<Bitfield>(Value);
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                LoadInst Class
 //===----------------------------------------------------------------------===//
 
 /// An instruction for reading from memory. This uses the SubclassData field in
 /// Value to store whether or not the load is volatile.
 class LoadInst : public UnaryInstruction {
   using VolatileField = BoolBitfieldElementT<0>;
   using AlignmentField = AlignmentBitfieldElementT<VolatileField::NextBit>;
   using OrderingField = AtomicOrderingBitfieldElementT<AlignmentField::NextBit>;
   static_assert(
       Bitfield::areContiguous<VolatileField, AlignmentField, OrderingField>(),
       "Bitfields must be contiguous");
 
   void AssertOK();
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   LoadInst *cloneImpl() const;
 
 public:
   LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr,
            InsertPosition InsertBefore);
   LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
            InsertPosition InsertBefore);
   LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
            Align Align, InsertPosition InsertBefore = nullptr);
   LoadInst(Type *Ty, Value *Ptr, const Twine &NameStr, bool isVolatile,
            Align Align, AtomicOrdering Order,
            SyncScope::ID SSID = SyncScope::System,
            InsertPosition InsertBefore = nullptr);
 
   /// Return true if this is a load from a volatile memory location.
   bool isVolatile() const { return getSubclassData<VolatileField>(); }
 
   /// Specify whether this is a volatile load or not.
   void setVolatile(bool V) { setSubclassData<VolatileField>(V); }
 
   /// Return the alignment of the access that is being performed.
   Align getAlign() const {
     return Align(1ULL << (getSubclassData<AlignmentField>()));
   }
 
   void setAlignment(Align Align) {
     setSubclassData<AlignmentField>(Log2(Align));
   }
 
   /// Returns the ordering constraint of this load instruction.
   AtomicOrdering getOrdering() const {
     return getSubclassData<OrderingField>();
   }
   /// Sets the ordering constraint of this load instruction.  May not be Release
   /// or AcquireRelease.
   void setOrdering(AtomicOrdering Ordering) {
     setSubclassData<OrderingField>(Ordering);
   }
 
   /// Returns the synchronization scope ID of this load instruction.
   SyncScope::ID getSyncScopeID() const {
     return SSID;
   }
 
   /// Sets the synchronization scope ID of this load instruction.
   void setSyncScopeID(SyncScope::ID SSID) {
     this->SSID = SSID;
   }
 
   /// Sets the ordering constraint and the synchronization scope ID of this load
   /// instruction.
   void setAtomic(AtomicOrdering Ordering,
                  SyncScope::ID SSID = SyncScope::System) {
     setOrdering(Ordering);
     setSyncScopeID(SSID);
   }
 
   bool isSimple() const { return !isAtomic() && !isVolatile(); }
 
   bool isUnordered() const {
     return (getOrdering() == AtomicOrdering::NotAtomic ||
             getOrdering() == AtomicOrdering::Unordered) &&
            !isVolatile();
   }
 
   Value *getPointerOperand() { return getOperand(0); }
   const Value *getPointerOperand() const { return getOperand(0); }
   static unsigned getPointerOperandIndex() { return 0U; }
   Type *getPointerOperandType() const { return getPointerOperand()->getType(); }
 
   /// Returns the address space of the pointer operand.
   unsigned getPointerAddressSpace() const {
     return getPointerOperandType()->getPointerAddressSpace();
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::Load;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   // Shadow Instruction::setInstructionSubclassData with a private forwarding
   // method so that subclasses cannot accidentally use it.
   template <typename Bitfield>
   void setSubclassData(typename Bitfield::Type Value) {
     Instruction::setSubclassData<Bitfield>(Value);
   }
 
   /// The synchronization scope ID of this load instruction.  Not quite enough
   /// room in SubClassData for everything, so synchronization scope ID gets its
   /// own field.
   SyncScope::ID SSID;
 };
 
 //===----------------------------------------------------------------------===//
 //                                StoreInst Class
 //===----------------------------------------------------------------------===//
 
 /// An instruction for storing to memory.
 class StoreInst : public Instruction {
   using VolatileField = BoolBitfieldElementT<0>;
   using AlignmentField = AlignmentBitfieldElementT<VolatileField::NextBit>;
   using OrderingField = AtomicOrderingBitfieldElementT<AlignmentField::NextBit>;
   static_assert(
       Bitfield::areContiguous<VolatileField, AlignmentField, OrderingField>(),
       "Bitfields must be contiguous");
 
   void AssertOK();
 
   constexpr static IntrusiveOperandsAllocMarker AllocMarker{2};
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   StoreInst *cloneImpl() const;
 
 public:
   StoreInst(Value *Val, Value *Ptr, InsertPosition InsertBefore);
   StoreInst(Value *Val, Value *Ptr, bool isVolatile,
             InsertPosition InsertBefore);
   StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
             InsertPosition InsertBefore = nullptr);
   StoreInst(Value *Val, Value *Ptr, bool isVolatile, Align Align,
             AtomicOrdering Order, SyncScope::ID SSID = SyncScope::System,
             InsertPosition InsertBefore = nullptr);
 
   // allocate space for exactly two operands
   void *operator new(size_t S) { return User::operator new(S, AllocMarker); }
   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.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   Align getAlign() const {
     return Align(1ULL << (getSubclassData<AlignmentField>()));
   }
 
   void setAlignment(Align Align) {
     setSubclassData<AlignmentField>(Log2(Align));
   }
 
   /// Returns the ordering constraint of this store instruction.
   AtomicOrdering getOrdering() const {
     return getSubclassData<OrderingField>();
   }
 
   /// Sets the ordering constraint of this store instruction.  May not be
   /// Acquire or AcquireRelease.
   void setOrdering(AtomicOrdering Ordering) {
     setSubclassData<OrderingField>(Ordering);
   }
 
   /// Returns the synchronization scope ID of this store instruction.
   SyncScope::ID getSyncScopeID() const {
     return SSID;
   }
 
   /// Sets the synchronization scope ID of this store instruction.
   void setSyncScopeID(SyncScope::ID SSID) {
     this->SSID = SSID;
   }
 
   /// Sets the ordering constraint and the synchronization scope ID of this
   /// store instruction.
   void setAtomic(AtomicOrdering Ordering,
                  SyncScope::ID SSID = SyncScope::System) {
     setOrdering(Ordering);
     setSyncScopeID(SSID);
   }
 
   bool isSimple() const { return !isAtomic() && !isVolatile(); }
 
   bool isUnordered() const {
     return (getOrdering() == AtomicOrdering::NotAtomic ||
             getOrdering() == AtomicOrdering::Unordered) &&
            !isVolatile();
   }
 
   Value *getValueOperand() { return getOperand(0); }
   const Value *getValueOperand() const { return getOperand(0); }
 
   Value *getPointerOperand() { return getOperand(1); }
   const Value *getPointerOperand() const { return getOperand(1); }
   static unsigned getPointerOperandIndex() { return 1U; }
   Type *getPointerOperandType() const { return getPointerOperand()->getType(); }
 
   /// Returns the address space of the pointer operand.
   unsigned getPointerAddressSpace() const {
     return getPointerOperandType()->getPointerAddressSpace();
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::Store;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   // Shadow Instruction::setInstructionSubclassData with a private forwarding
   // method so that subclasses cannot accidentally use it.
   template <typename Bitfield>
   void setSubclassData(typename Bitfield::Type Value) {
     Instruction::setSubclassData<Bitfield>(Value);
   }
 
   /// The synchronization scope ID of this store instruction.  Not quite enough
   /// room in SubClassData for everything, so synchronization scope ID gets its
   /// own field.
   SyncScope::ID SSID;
 };
 
 template <>
 struct OperandTraits<StoreInst> : public FixedNumOperandTraits<StoreInst, 2> {
 };
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(StoreInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                                FenceInst Class
 //===----------------------------------------------------------------------===//
 
 /// An instruction for ordering other memory operations.
 class FenceInst : public Instruction {
   using OrderingField = AtomicOrderingBitfieldElementT<0>;
 
   constexpr static IntrusiveOperandsAllocMarker AllocMarker{0};
 
   void Init(AtomicOrdering Ordering, SyncScope::ID SSID);
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   FenceInst *cloneImpl() const;
 
 public:
   // Ordering may only be Acquire, Release, AcquireRelease, or
   // SequentiallyConsistent.
   FenceInst(LLVMContext &C, AtomicOrdering Ordering,
             SyncScope::ID SSID = SyncScope::System,
             InsertPosition InsertBefore = nullptr);
 
   // allocate space for exactly zero operands
   void *operator new(size_t S) { return User::operator new(S, AllocMarker); }
   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.
   void setOrdering(AtomicOrdering Ordering) {
     setSubclassData<OrderingField>(Ordering);
   }
 
   /// Returns the synchronization scope ID of this fence instruction.
   SyncScope::ID getSyncScopeID() const {
     return SSID;
   }
 
   /// Sets the synchronization scope ID of this fence instruction.
   void setSyncScopeID(SyncScope::ID SSID) {
     this->SSID = SSID;
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::Fence;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   // Shadow Instruction::setInstructionSubclassData with a private forwarding
   // method so that subclasses cannot accidentally use it.
   template <typename Bitfield>
   void setSubclassData(typename Bitfield::Type Value) {
     Instruction::setSubclassData<Bitfield>(Value);
   }
 
   /// The synchronization scope ID of this fence instruction.  Not quite enough
   /// room in SubClassData for everything, so synchronization scope ID gets its
   /// own field.
   SyncScope::ID SSID;
 };
 
 //===----------------------------------------------------------------------===//
 //                                AtomicCmpXchgInst Class
 //===----------------------------------------------------------------------===//
 
 /// An instruction that atomically checks whether a
 /// specified value is in a memory location, and, if it is, stores a new value
 /// there. The value returned by this instruction is a pair containing the
 /// original value as first element, and an i1 indicating success (true) or
 /// failure (false) as second element.
 ///
 class AtomicCmpXchgInst : public Instruction {
   void Init(Value *Ptr, Value *Cmp, Value *NewVal, Align Align,
             AtomicOrdering SuccessOrdering, AtomicOrdering FailureOrdering,
             SyncScope::ID SSID);
 
   template <unsigned Offset>
   using AtomicOrderingBitfieldElement =
       typename Bitfield::Element<AtomicOrdering, Offset, 3,
                                  AtomicOrdering::LAST>;
 
   constexpr static IntrusiveOperandsAllocMarker AllocMarker{3};
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   AtomicCmpXchgInst *cloneImpl() const;
 
 public:
   AtomicCmpXchgInst(Value *Ptr, Value *Cmp, Value *NewVal, Align Alignment,
                     AtomicOrdering SuccessOrdering,
                     AtomicOrdering FailureOrdering, SyncScope::ID SSID,
                     InsertPosition InsertBefore = nullptr);
 
   // allocate space for exactly three operands
   void *operator new(size_t S) { return User::operator new(S, AllocMarker); }
   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 =
       AlignmentBitfieldElementT<FailureOrderingField::NextBit>;
   static_assert(
       Bitfield::areContiguous<VolatileField, WeakField, SuccessOrderingField,
                               FailureOrderingField, AlignmentField>(),
       "Bitfields must be contiguous");
 
   /// Return the alignment of the memory that is being allocated by the
   /// instruction.
   Align getAlign() const {
     return Align(1ULL << getSubclassData<AlignmentField>());
   }
 
   void setAlignment(Align Align) {
     setSubclassData<AlignmentField>(Log2(Align));
   }
 
   /// Return true if this is a cmpxchg from a volatile memory
   /// location.
   ///
   bool isVolatile() const { return getSubclassData<VolatileField>(); }
 
   /// Specify whether this is a volatile cmpxchg.
   ///
   void setVolatile(bool V) { setSubclassData<VolatileField>(V); }
 
   /// Return true if this cmpxchg may spuriously fail.
   bool isWeak() const { return getSubclassData<WeakField>(); }
 
   void setWeak(bool IsWeak) { setSubclassData<WeakField>(IsWeak); }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   static bool isValidSuccessOrdering(AtomicOrdering Ordering) {
     return Ordering != AtomicOrdering::NotAtomic &&
            Ordering != AtomicOrdering::Unordered;
   }
 
   static bool isValidFailureOrdering(AtomicOrdering Ordering) {
     return Ordering != AtomicOrdering::NotAtomic &&
            Ordering != AtomicOrdering::Unordered &&
            Ordering != AtomicOrdering::AcquireRelease &&
            Ordering != AtomicOrdering::Release;
   }
 
   /// Returns the success ordering constraint of this cmpxchg instruction.
   AtomicOrdering getSuccessOrdering() const {
     return getSubclassData<SuccessOrderingField>();
   }
 
   /// Sets the success ordering constraint of this cmpxchg instruction.
   void setSuccessOrdering(AtomicOrdering Ordering) {
     assert(isValidSuccessOrdering(Ordering) &&
            "invalid CmpXchg success ordering");
     setSubclassData<SuccessOrderingField>(Ordering);
   }
 
   /// Returns the failure ordering constraint of this cmpxchg instruction.
   AtomicOrdering getFailureOrdering() const {
     return getSubclassData<FailureOrderingField>();
   }
 
   /// Sets the failure ordering constraint of this cmpxchg instruction.
   void setFailureOrdering(AtomicOrdering Ordering) {
     assert(isValidFailureOrdering(Ordering) &&
            "invalid CmpXchg failure ordering");
     setSubclassData<FailureOrderingField>(Ordering);
   }
 
   /// Returns a single ordering which is at least as strong as both the
   /// success and failure orderings for this cmpxchg.
   AtomicOrdering getMergedOrdering() const {
     if (getFailureOrdering() == AtomicOrdering::SequentiallyConsistent)
       return AtomicOrdering::SequentiallyConsistent;
     if (getFailureOrdering() == AtomicOrdering::Acquire) {
       if (getSuccessOrdering() == AtomicOrdering::Monotonic)
         return AtomicOrdering::Acquire;
       if (getSuccessOrdering() == AtomicOrdering::Release)
         return AtomicOrdering::AcquireRelease;
     }
     return getSuccessOrdering();
   }
 
   /// Returns the synchronization scope ID of this cmpxchg instruction.
   SyncScope::ID getSyncScopeID() const {
     return SSID;
   }
 
   /// Sets the synchronization scope ID of this cmpxchg instruction.
   void setSyncScopeID(SyncScope::ID SSID) {
     this->SSID = SSID;
   }
 
   Value *getPointerOperand() { return getOperand(0); }
   const Value *getPointerOperand() const { return getOperand(0); }
   static unsigned getPointerOperandIndex() { return 0U; }
 
   Value *getCompareOperand() { return getOperand(1); }
   const Value *getCompareOperand() const { return getOperand(1); }
 
   Value *getNewValOperand() { return getOperand(2); }
   const Value *getNewValOperand() const { return getOperand(2); }
 
   /// Returns the address space of the pointer operand.
   unsigned getPointerAddressSpace() const {
     return getPointerOperand()->getType()->getPointerAddressSpace();
   }
 
   /// Returns the strongest permitted ordering on failure, given the
   /// desired ordering on success.
   ///
   /// If the comparison in a cmpxchg operation fails, there is no atomic store
   /// so release semantics cannot be provided. So this function drops explicit
   /// Release requests from the AtomicOrdering. A SequentiallyConsistent
   /// operation would remain SequentiallyConsistent.
   static AtomicOrdering
   getStrongestFailureOrdering(AtomicOrdering SuccessOrdering) {
     switch (SuccessOrdering) {
     default:
       llvm_unreachable("invalid cmpxchg success ordering");
     case AtomicOrdering::Release:
     case AtomicOrdering::Monotonic:
       return AtomicOrdering::Monotonic;
     case AtomicOrdering::AcquireRelease:
     case AtomicOrdering::Acquire:
       return AtomicOrdering::Acquire;
     case AtomicOrdering::SequentiallyConsistent:
       return AtomicOrdering::SequentiallyConsistent;
     }
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::AtomicCmpXchg;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   // Shadow Instruction::setInstructionSubclassData with a private forwarding
   // method so that subclasses cannot accidentally use it.
   template <typename Bitfield>
   void setSubclassData(typename Bitfield::Type Value) {
     Instruction::setSubclassData<Bitfield>(Value);
   }
 
   /// The synchronization scope ID of this cmpxchg instruction.  Not quite
   /// enough room in SubClassData for everything, so synchronization scope ID
   /// gets its own field.
   SyncScope::ID SSID;
 };
 
 template <>
 struct OperandTraits<AtomicCmpXchgInst> :
     public FixedNumOperandTraits<AtomicCmpXchgInst, 3> {
 };
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(AtomicCmpXchgInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                                AtomicRMWInst Class
 //===----------------------------------------------------------------------===//
 
 /// an instruction that atomically reads a memory location,
 /// combines it with another value, and then stores the result back.  Returns
 /// the old value.
 ///
 class AtomicRMWInst : public Instruction {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   AtomicRMWInst *cloneImpl() const;
 
 public:
   /// This enumeration lists the possible modifications atomicrmw can make.  In
   /// the descriptions, 'p' is the pointer to the instruction's memory location,
   /// 'old' is the initial value of *p, and 'v' is the other value passed to the
   /// instruction.  These instructions always return 'old'.
   enum BinOp : unsigned {
     /// *p = v
     Xchg,
     /// *p = old + v
     Add,
     /// *p = old - v
     Sub,
     /// *p = old & v
     And,
     /// *p = ~(old & v)
     Nand,
     /// *p = old | v
     Or,
     /// *p = old ^ v
     Xor,
     /// *p = old >signed v ? old : v
     Max,
     /// *p = old <signed v ? old : v
     Min,
     /// *p = old >unsigned v ? old : v
     UMax,
     /// *p = old <unsigned v ? old : v
     UMin,
 
     /// *p = old + v
     FAdd,
 
     /// *p = old - v
     FSub,
 
     /// *p = maxnum(old, v)
     /// \p maxnum matches the behavior of \p llvm.maxnum.*.
     FMax,
 
     /// *p = minnum(old, v)
     /// \p minnum matches the behavior of \p llvm.minnum.*.
     FMin,
 
     /// Increment one up to a maximum value.
     /// *p = (old u>= v) ? 0 : (old + 1)
     UIncWrap,
 
     /// Decrement one until a minimum value or zero.
     /// *p = ((old == 0) || (old u> v)) ? v : (old - 1)
     UDecWrap,
 
     /// Subtract only if no unsigned overflow.
     /// *p = (old u>= v) ? old - v : old
     USubCond,
 
     /// *p = usub.sat(old, v)
     /// \p usub.sat matches the behavior of \p llvm.usub.sat.*.
     USubSat,
 
     FIRST_BINOP = Xchg,
     LAST_BINOP = USubSat,
     BAD_BINOP
   };
 
 private:
   template <unsigned Offset>
   using AtomicOrderingBitfieldElement =
       typename Bitfield::Element<AtomicOrdering, Offset, 3,
                                  AtomicOrdering::LAST>;
 
   template <unsigned Offset>
   using BinOpBitfieldElement =
       typename Bitfield::Element<BinOp, Offset, 5, BinOp::LAST_BINOP>;
 
   constexpr static IntrusiveOperandsAllocMarker AllocMarker{2};
 
 public:
   AtomicRMWInst(BinOp Operation, Value *Ptr, Value *Val, Align Alignment,
                 AtomicOrdering Ordering, SyncScope::ID SSID,
                 InsertPosition InsertBefore = nullptr);
 
   // allocate space for exactly two operands
   void *operator new(size_t S) { return User::operator new(S, AllocMarker); }
   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>(),
                 "Bitfields must be contiguous");
 
   BinOp getOperation() const { return getSubclassData<OperationField>(); }
 
   static StringRef getOperationName(BinOp Op);
 
   static bool isFPOperation(BinOp Op) {
     switch (Op) {
     case AtomicRMWInst::FAdd:
     case AtomicRMWInst::FSub:
     case AtomicRMWInst::FMax:
     case AtomicRMWInst::FMin:
       return true;
     default:
       return false;
     }
   }
 
   void setOperation(BinOp Operation) {
     setSubclassData<OperationField>(Operation);
   }
 
   /// Return the alignment of the memory that is being allocated by the
   /// instruction.
   Align getAlign() const {
     return Align(1ULL << getSubclassData<AlignmentField>());
   }
 
   void setAlignment(Align Align) {
     setSubclassData<AlignmentField>(Log2(Align));
   }
 
   /// Return true if this is a RMW on a volatile memory location.
   ///
   bool isVolatile() const { return getSubclassData<VolatileField>(); }
 
   /// Specify whether this is a volatile RMW or not.
   ///
   void setVolatile(bool V) { setSubclassData<VolatileField>(V); }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   /// Returns the ordering constraint of this rmw instruction.
   AtomicOrdering getOrdering() const {
     return getSubclassData<AtomicOrderingField>();
   }
 
   /// Sets the ordering constraint of this rmw instruction.
   void setOrdering(AtomicOrdering Ordering) {
     assert(Ordering != AtomicOrdering::NotAtomic &&
            "atomicrmw instructions can only be atomic.");
     assert(Ordering != AtomicOrdering::Unordered &&
            "atomicrmw instructions cannot be unordered.");
     setSubclassData<AtomicOrderingField>(Ordering);
   }
 
   /// Returns the synchronization scope ID of this rmw instruction.
   SyncScope::ID getSyncScopeID() const {
     return SSID;
   }
 
   /// Sets the synchronization scope ID of this rmw instruction.
   void setSyncScopeID(SyncScope::ID SSID) {
     this->SSID = SSID;
   }
 
   Value *getPointerOperand() { return getOperand(0); }
   const Value *getPointerOperand() const { return getOperand(0); }
   static unsigned getPointerOperandIndex() { return 0U; }
 
   Value *getValOperand() { return getOperand(1); }
   const Value *getValOperand() const { return getOperand(1); }
 
   /// Returns the address space of the pointer operand.
   unsigned getPointerAddressSpace() const {
     return getPointerOperand()->getType()->getPointerAddressSpace();
   }
 
   bool isFloatingPointOperation() const {
     return isFPOperation(getOperation());
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::AtomicRMW;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   void Init(BinOp Operation, Value *Ptr, Value *Val, Align Align,
             AtomicOrdering Ordering, SyncScope::ID SSID);
 
   // Shadow Instruction::setInstructionSubclassData with a private forwarding
   // method so that subclasses cannot accidentally use it.
   template <typename Bitfield>
   void setSubclassData(typename Bitfield::Type Value) {
     Instruction::setSubclassData<Bitfield>(Value);
   }
 
   /// The synchronization scope ID of this rmw instruction.  Not quite enough
   /// room in SubClassData for everything, so synchronization scope ID gets its
   /// own field.
   SyncScope::ID SSID;
 };
 
 template <>
 struct OperandTraits<AtomicRMWInst>
     : public FixedNumOperandTraits<AtomicRMWInst,2> {
 };
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(AtomicRMWInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                             GetElementPtrInst Class
 //===----------------------------------------------------------------------===//
 
 // checkGEPType - Simple wrapper function to give a better assertion failure
 // message on bad indexes for a gep instruction.
 //
 inline Type *checkGEPType(Type *Ty) {
   assert(Ty && "Invalid GetElementPtrInst indices for type!");
   return Ty;
 }
 
 /// an instruction for type-safe pointer arithmetic to
 /// access elements of arrays and structs
 ///
 class GetElementPtrInst : public Instruction {
   Type *SourceElementType;
   Type *ResultElementType;
 
   GetElementPtrInst(const GetElementPtrInst &GEPI, AllocInfo AllocInfo);
 
   /// Constructors - Create a getelementptr instruction with a base pointer an
   /// list of indices. The first and second ctor can optionally insert before an
   /// existing instruction, the third appends the new instruction to the
   /// specified BasicBlock.
   inline GetElementPtrInst(Type *PointeeType, Value *Ptr,
                            ArrayRef<Value *> IdxList, AllocInfo AllocInfo,
                            const Twine &NameStr, InsertPosition InsertBefore);
 
   void init(Value *Ptr, ArrayRef<Value *> IdxList, const Twine &NameStr);
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   GetElementPtrInst *cloneImpl() const;
 
 public:
   static GetElementPtrInst *Create(Type *PointeeType, Value *Ptr,
                                    ArrayRef<Value *> IdxList,
                                    const Twine &NameStr = "",
                                    InsertPosition InsertBefore = nullptr) {
     unsigned Values = 1 + unsigned(IdxList.size());
     assert(PointeeType && "Must specify element type");
     IntrusiveOperandsAllocMarker AllocMarker{Values};
     return new (AllocMarker) GetElementPtrInst(
         PointeeType, Ptr, IdxList, AllocMarker, NameStr, InsertBefore);
   }
 
   static GetElementPtrInst *Create(Type *PointeeType, Value *Ptr,
                                    ArrayRef<Value *> IdxList, GEPNoWrapFlags NW,
                                    const Twine &NameStr = "",
                                    InsertPosition InsertBefore = nullptr) {
     GetElementPtrInst *GEP =
         Create(PointeeType, Ptr, IdxList, NameStr, InsertBefore);
     GEP->setNoWrapFlags(NW);
     return GEP;
   }
 
   /// Create an "inbounds" getelementptr. See the documentation for the
   /// "inbounds" flag in LangRef.html for details.
   static GetElementPtrInst *
   CreateInBounds(Type *PointeeType, Value *Ptr, ArrayRef<Value *> IdxList,
                  const Twine &NameStr = "",
                  InsertPosition InsertBefore = nullptr) {
     return Create(PointeeType, Ptr, IdxList, GEPNoWrapFlags::inBounds(),
                   NameStr, InsertBefore);
   }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   Type *getSourceElementType() const { return SourceElementType; }
 
   void setSourceElementType(Type *Ty) { SourceElementType = Ty; }
   void setResultElementType(Type *Ty) { ResultElementType = Ty; }
 
   Type *getResultElementType() const {
     return ResultElementType;
   }
 
   /// Returns the address space of this instruction's pointer type.
   unsigned getAddressSpace() const {
     // Note that this is always the same as the pointer operand's address space
     // and that is cheaper to compute, so cheat here.
     return getPointerAddressSpace();
   }
 
   /// Returns the result type of a getelementptr with the given source
   /// element type and indexes.
   ///
   /// Null is returned if the indices are invalid for the specified
   /// source element type.
   static Type *getIndexedType(Type *Ty, ArrayRef<Value *> IdxList);
   static Type *getIndexedType(Type *Ty, ArrayRef<Constant *> IdxList);
   static Type *getIndexedType(Type *Ty, ArrayRef<uint64_t> IdxList);
 
   /// Return the type of the element at the given index of an indexable
   /// type.  This is equivalent to "getIndexedType(Agg, {Zero, Idx})".
   ///
   /// Returns null if the type can't be indexed, or the given index is not
   /// legal for the given type.
   static Type *getTypeAtIndex(Type *Ty, Value *Idx);
   static Type *getTypeAtIndex(Type *Ty, uint64_t Idx);
 
   inline op_iterator       idx_begin()       { return op_begin()+1; }
   inline const_op_iterator idx_begin() const { return op_begin()+1; }
   inline op_iterator       idx_end()         { return op_end(); }
   inline const_op_iterator idx_end()   const { return op_end(); }
 
   inline iterator_range<op_iterator> indices() {
     return make_range(idx_begin(), idx_end());
   }
 
   inline iterator_range<const_op_iterator> indices() const {
     return make_range(idx_begin(), idx_end());
   }
 
   Value *getPointerOperand() {
     return getOperand(0);
   }
   const Value *getPointerOperand() const {
     return getOperand(0);
   }
   static unsigned getPointerOperandIndex() {
     return 0U;    // get index for modifying correct operand.
   }
 
   /// Method to return the pointer operand as a
   /// PointerType.
   Type *getPointerOperandType() const {
     return getPointerOperand()->getType();
   }
 
   /// Returns the address space of the pointer operand.
   unsigned getPointerAddressSpace() const {
     return getPointerOperandType()->getPointerAddressSpace();
   }
 
   /// Returns the pointer type returned by the GEP
   /// instruction, which may be a vector of pointers.
   static Type *getGEPReturnType(Value *Ptr, ArrayRef<Value *> IdxList) {
     // Vector GEP
     Type *Ty = Ptr->getType();
     if (Ty->isVectorTy())
       return Ty;
 
     for (Value *Index : IdxList)
       if (auto *IndexVTy = dyn_cast<VectorType>(Index->getType())) {
         ElementCount EltCount = IndexVTy->getElementCount();
         return VectorType::get(Ty, EltCount);
       }
     // Scalar GEP
     return Ty;
   }
 
   unsigned getNumIndices() const {  // Note: always non-negative
     return getNumOperands() - 1;
   }
 
   bool hasIndices() const {
     return getNumOperands() > 1;
   }
 
   /// Return true if all of the indices of this GEP are
   /// zeros.  If so, the result pointer and the first operand have the same
   /// value, just potentially different types.
   bool hasAllZeroIndices() const;
 
   /// Return true if all of the indices of this GEP are
   /// constant integers.  If so, the result pointer and the first operand have
   /// a constant offset between them.
   bool hasAllConstantIndices() const;
 
   /// Set nowrap flags for GEP instruction.
   void setNoWrapFlags(GEPNoWrapFlags NW);
 
   /// Set or clear the inbounds flag on this GEP instruction.
   /// See LangRef.html for the meaning of inbounds on a getelementptr.
   /// TODO: Remove this method in favor of setNoWrapFlags().
   void setIsInBounds(bool b = true);
 
   /// Get the nowrap flags for the GEP instruction.
   GEPNoWrapFlags getNoWrapFlags() const;
 
   /// Determine whether the GEP has the inbounds flag.
   bool isInBounds() const;
 
   /// Determine whether the GEP has the nusw flag.
   bool hasNoUnsignedSignedWrap() const;
 
   /// Determine whether the GEP has the nuw flag.
   bool hasNoUnsignedWrap() const;
 
   /// Accumulate the constant address offset of this GEP if possible.
   ///
   /// This routine accepts an APInt into which it will accumulate the constant
   /// offset of this GEP if the GEP is in fact constant. If the GEP is not
   /// all-constant, it returns false and the value of the offset APInt is
   /// undefined (it is *not* preserved!). The APInt passed into this routine
   /// must be at least as wide as the IntPtr type for the address space of
   /// the base GEP pointer.
   bool accumulateConstantOffset(const DataLayout &DL, APInt &Offset) const;
   bool collectOffset(const DataLayout &DL, unsigned BitWidth,
                      SmallMapVector<Value *, APInt, 4> &VariableOffsets,
                      APInt &ConstantOffset) const;
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return (I->getOpcode() == Instruction::GetElementPtr);
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 template <>
 struct OperandTraits<GetElementPtrInst>
     : public VariadicOperandTraits<GetElementPtrInst> {};
 
 GetElementPtrInst::GetElementPtrInst(Type *PointeeType, Value *Ptr,
                                      ArrayRef<Value *> IdxList,
                                      AllocInfo AllocInfo, const Twine &NameStr,
                                      InsertPosition InsertBefore)
     : Instruction(getGEPReturnType(Ptr, IdxList), GetElementPtr, AllocInfo,
                   InsertBefore),
       SourceElementType(PointeeType),
       ResultElementType(getIndexedType(PointeeType, IdxList)) {
   init(Ptr, IdxList, NameStr);
 }
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(GetElementPtrInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                               ICmpInst Class
 //===----------------------------------------------------------------------===//
 
 /// This instruction compares its operands according to the predicate given
 /// to the constructor. It only operates on integers or pointers. The operands
 /// must be identical types.
 /// Represent an integer comparison operator.
 class ICmpInst: public CmpInst {
   void AssertOK() {
     assert(isIntPredicate() &&
            "Invalid ICmp predicate value");
     assert(getOperand(0)->getType() == getOperand(1)->getType() &&
           "Both operands to ICmp instruction are not of the same type!");
     // Check that the operands are the right type
     assert((getOperand(0)->getType()->isIntOrIntVectorTy() ||
             getOperand(0)->getType()->isPtrOrPtrVectorTy()) &&
            "Invalid operand types for ICmp instruction");
   }
 
   enum { SameSign = (1 << 0) };
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical ICmpInst
   ICmpInst *cloneImpl() const;
 
 public:
   /// Constructor with insertion semantics.
   ICmpInst(InsertPosition InsertBefore, ///< Where to insert
            Predicate pred, ///< The predicate to use for the comparison
            Value *LHS,     ///< The left-hand-side of the expression
            Value *RHS,     ///< The right-hand-side of the expression
            const Twine &NameStr = "" ///< Name of the instruction
            )
       : CmpInst(makeCmpResultType(LHS->getType()), Instruction::ICmp, pred, LHS,
                 RHS, NameStr, InsertBefore) {
 #ifndef NDEBUG
   AssertOK();
 #endif
   }
 
   /// Constructor with no-insertion semantics
   ICmpInst(
     Predicate pred, ///< The predicate to use for the comparison
     Value *LHS,     ///< The left-hand-side of the expression
     Value *RHS,     ///< The right-hand-side of the expression
     const Twine &NameStr = "" ///< Name of the instruction
   ) : CmpInst(makeCmpResultType(LHS->getType()),
               Instruction::ICmp, pred, LHS, RHS, NameStr) {
 #ifndef NDEBUG
   AssertOK();
 #endif
   }
 
   /// @returns the predicate along with samesign information.
   CmpPredicate getCmpPredicate() const {
     return {getPredicate(), hasSameSign()};
   }
 
   /// @returns the inverse predicate along with samesign information: static
   /// variant.
   static CmpPredicate getInverseCmpPredicate(CmpPredicate Pred) {
     return {getInversePredicate(Pred), Pred.hasSameSign()};
   }
 
   /// @returns the inverse predicate along with samesign information.
   CmpPredicate getInverseCmpPredicate() const {
     return getInverseCmpPredicate(getCmpPredicate());
   }
 
   /// @returns the swapped predicate along with samesign information: static
   /// variant.
   static CmpPredicate getSwappedCmpPredicate(CmpPredicate Pred) {
     return {getSwappedPredicate(Pred), Pred.hasSameSign()};
   }
 
   /// @returns the swapped predicate along with samesign information.
   CmpPredicate getSwappedCmpPredicate() const {
     return getSwappedCmpPredicate(getCmpPredicate());
   }
 
   /// For example, EQ->EQ, SLE->SLE, UGT->SGT, etc.
   /// @returns the predicate that would be the result if the operand were
   /// regarded as signed.
   /// Return the signed version of the predicate.
   Predicate getSignedPredicate() const {
     return getSignedPredicate(getPredicate());
   }
 
   /// Return the signed version of the predicate: static variant.
   static Predicate getSignedPredicate(Predicate Pred);
 
   /// For example, EQ->EQ, SLE->ULE, UGT->UGT, etc.
   /// @returns the predicate that would be the result if the operand were
   /// regarded as unsigned.
   /// Return the unsigned version of the predicate.
   Predicate getUnsignedPredicate() const {
     return getUnsignedPredicate(getPredicate());
   }
 
   /// Return the unsigned version of the predicate: static variant.
   static Predicate getUnsignedPredicate(Predicate Pred);
 
   /// For example, SLT->ULT, ULT->SLT, SLE->ULE, ULE->SLE, EQ->EQ
   /// @returns the unsigned version of the signed predicate pred or
   ///          the signed version of the signed predicate pred.
   /// Static variant.
   static Predicate getFlippedSignednessPredicate(Predicate Pred);
 
   /// For example, SLT->ULT, ULT->SLT, SLE->ULE, ULE->SLE, EQ->EQ
   /// @returns the unsigned version of the signed predicate pred or
   ///          the signed version of the signed predicate pred.
   Predicate getFlippedSignednessPredicate() const {
     return getFlippedSignednessPredicate(getPredicate());
   }
 
   /// Determine if Pred1 implies Pred2 is true, false, or if nothing can be
   /// inferred about the implication, when two compares have matching operands.
   static std::optional<bool> isImpliedByMatchingCmp(CmpPredicate Pred1,
                                                     CmpPredicate Pred2);
 
   void setSameSign(bool B = true) {
     SubclassOptionalData = (SubclassOptionalData & ~SameSign) | (B * SameSign);
   }
 
   /// An icmp instruction, which can be marked as "samesign", indicating that
   /// the two operands have the same sign. This means that we can convert
   /// "slt" to "ult" and vice versa, which enables more optimizations.
   bool hasSameSign() const { return SubclassOptionalData & SameSign; }
 
   /// Return true if this predicate is either EQ or NE.  This also
   /// tests for commutativity.
   static bool isEquality(Predicate P) {
     return P == ICMP_EQ || P == ICMP_NE;
   }
 
   /// Return true if this predicate is either EQ or NE.  This also
   /// tests for commutativity.
   bool isEquality() const {
     return isEquality(getPredicate());
   }
 
   /// @returns true if the predicate is commutative
   /// Determine if this relation is commutative.
   static bool isCommutative(Predicate P) { return isEquality(P); }
 
   /// @returns true if the predicate of this ICmpInst is commutative
   /// Determine if this relation is commutative.
   bool isCommutative() const { return isCommutative(getPredicate()); }
 
   /// Return true if the predicate is relational (not EQ or NE).
   ///
   bool isRelational() const {
     return !isEquality();
   }
 
   /// Return true if the predicate is relational (not EQ or NE).
   ///
   static bool isRelational(Predicate P) {
     return !isEquality(P);
   }
 
   /// Return true if the predicate is SGT or UGT.
   ///
   static bool isGT(Predicate P) {
     return P == ICMP_SGT || P == ICMP_UGT;
   }
 
   /// Return true if the predicate is SLT or ULT.
   ///
   static bool isLT(Predicate P) {
     return P == ICMP_SLT || P == ICMP_ULT;
   }
 
   /// Return true if the predicate is SGE or UGE.
   ///
   static bool isGE(Predicate P) {
     return P == ICMP_SGE || P == ICMP_UGE;
   }
 
   /// Return true if the predicate is SLE or ULE.
   ///
   static bool isLE(Predicate P) {
     return P == ICMP_SLE || P == ICMP_ULE;
   }
 
   /// Returns the sequence of all ICmp predicates.
   ///
   static auto predicates() { return ICmpPredicates(); }
 
   /// Exchange the two operands to this instruction in such a way that it does
   /// not modify the semantics of the instruction. The predicate value may be
   /// changed to retain the same result if the predicate is order dependent
   /// (e.g. ult).
   /// Swap operands and adjust predicate.
   void swapOperands() {
     setPredicate(getSwappedPredicate());
     Op<0>().swap(Op<1>());
   }
 
   /// Return result of `LHS Pred RHS` comparison.
   static bool compare(const APInt &LHS, const APInt &RHS,
                       ICmpInst::Predicate Pred);
 
   /// Return result of `LHS Pred RHS`, if it can be determined from the
   /// KnownBits. Otherwise return nullopt.
   static std::optional<bool> compare(const KnownBits &LHS, const KnownBits &RHS,
                                      ICmpInst::Predicate Pred);
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::ICmp;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                               FCmpInst Class
 //===----------------------------------------------------------------------===//
 
 /// This instruction compares its operands according to the predicate given
 /// to the constructor. It only operates on floating point values or packed
 /// vectors of floating point values. The operands must be identical types.
 /// Represents a floating point comparison operator.
 class FCmpInst: public CmpInst {
   void AssertOK() {
     assert(isFPPredicate() && "Invalid FCmp predicate value");
     assert(getOperand(0)->getType() == getOperand(1)->getType() &&
            "Both operands to FCmp instruction are not of the same type!");
     // Check that the operands are the right type
     assert(getOperand(0)->getType()->isFPOrFPVectorTy() &&
            "Invalid operand types for FCmp instruction");
   }
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical FCmpInst
   FCmpInst *cloneImpl() const;
 
 public:
   /// Constructor with insertion semantics.
   FCmpInst(InsertPosition InsertBefore, ///< Where to insert
            Predicate pred, ///< The predicate to use for the comparison
            Value *LHS,     ///< The left-hand-side of the expression
            Value *RHS,     ///< The right-hand-side of the expression
            const Twine &NameStr = "" ///< Name of the instruction
            )
       : CmpInst(makeCmpResultType(LHS->getType()), Instruction::FCmp, pred, LHS,
                 RHS, NameStr, InsertBefore) {
     AssertOK();
   }
 
   /// Constructor with no-insertion semantics
   FCmpInst(Predicate Pred, ///< The predicate to use for the comparison
            Value *LHS,     ///< The left-hand-side of the expression
            Value *RHS,     ///< The right-hand-side of the expression
            const Twine &NameStr = "", ///< Name of the instruction
            Instruction *FlagsSource = nullptr)
       : CmpInst(makeCmpResultType(LHS->getType()), Instruction::FCmp, Pred, LHS,
                 RHS, NameStr, nullptr, FlagsSource) {
     AssertOK();
   }
 
   /// @returns true if the predicate is EQ or NE.
   /// Determine if this is an equality predicate.
   static bool isEquality(Predicate Pred) {
     return Pred == FCMP_OEQ || Pred == FCMP_ONE || Pred == FCMP_UEQ ||
            Pred == FCMP_UNE;
   }
 
   /// @returns true if the predicate of this instruction is EQ or NE.
   /// Determine if this is an equality predicate.
   bool isEquality() const { return isEquality(getPredicate()); }
 
   /// @returns true if the predicate is commutative.
   /// Determine if this is a commutative predicate.
   static bool isCommutative(Predicate Pred) {
     return isEquality(Pred) || Pred == FCMP_FALSE || Pred == FCMP_TRUE ||
            Pred == FCMP_ORD || Pred == FCMP_UNO;
   }
 
   /// @returns true if the predicate of this instruction is commutative.
   /// Determine if this is a commutative predicate.
   bool isCommutative() const { return isCommutative(getPredicate()); }
 
   /// @returns true if the predicate is relational (not EQ or NE).
   /// Determine if this a relational predicate.
   bool isRelational() const { return !isEquality(); }
 
   /// Exchange the two operands to this instruction in such a way that it does
   /// not modify the semantics of the instruction. The predicate value may be
   /// changed to retain the same result if the predicate is order dependent
   /// (e.g. ult).
   /// Swap operands and adjust predicate.
   void swapOperands() {
     setPredicate(getSwappedPredicate());
     Op<0>().swap(Op<1>());
   }
 
   /// Returns the sequence of all FCmp predicates.
   ///
   static auto predicates() { return FCmpPredicates(); }
 
   /// Return result of `LHS Pred RHS` comparison.
   static bool compare(const APFloat &LHS, const APFloat &RHS,
                       FCmpInst::Predicate Pred);
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::FCmp;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 /// This class represents a function call, abstracting a target
 /// machine's calling convention.  This class uses low bit of the SubClassData
 /// field to indicate whether or not this is a tail call.  The rest of the bits
 /// hold the calling convention of the call.
 ///
 class CallInst : public CallBase {
   CallInst(const CallInst &CI, AllocInfo AllocInfo);
 
   /// Construct a CallInst from a range of arguments
   inline CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                   ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr,
                   AllocInfo AllocInfo, InsertPosition InsertBefore);
 
   inline CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                   const Twine &NameStr, AllocInfo AllocInfo,
                   InsertPosition InsertBefore)
       : CallInst(Ty, Func, Args, {}, NameStr, AllocInfo, InsertBefore) {}
 
   explicit CallInst(FunctionType *Ty, Value *F, const Twine &NameStr,
                     AllocInfo AllocInfo, InsertPosition InsertBefore);
 
   void init(FunctionType *FTy, Value *Func, ArrayRef<Value *> Args,
             ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr);
   void init(FunctionType *FTy, Value *Func, const Twine &NameStr);
 
   /// Compute the number of operands to allocate.
   static unsigned ComputeNumOperands(unsigned NumArgs,
                                      unsigned NumBundleInputs = 0) {
     // We need one operand for the called function, plus the input operand
     // counts provided.
     return 1 + NumArgs + NumBundleInputs;
   }
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   CallInst *cloneImpl() const;
 
 public:
   static CallInst *Create(FunctionType *Ty, Value *F, const Twine &NameStr = "",
                           InsertPosition InsertBefore = nullptr) {
     IntrusiveOperandsAllocMarker AllocMarker{ComputeNumOperands(0)};
     return new (AllocMarker)
         CallInst(Ty, F, NameStr, AllocMarker, InsertBefore);
   }
 
   static CallInst *Create(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                           const Twine &NameStr,
                           InsertPosition InsertBefore = nullptr) {
     IntrusiveOperandsAllocMarker AllocMarker{ComputeNumOperands(Args.size())};
     return new (AllocMarker)
         CallInst(Ty, Func, Args, {}, NameStr, AllocMarker, InsertBefore);
   }
 
   static CallInst *Create(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                           ArrayRef<OperandBundleDef> Bundles = {},
                           const Twine &NameStr = "",
                           InsertPosition InsertBefore = nullptr) {
     IntrusiveOperandsAndDescriptorAllocMarker AllocMarker{
         ComputeNumOperands(unsigned(Args.size()), CountBundleInputs(Bundles)),
         unsigned(Bundles.size() * sizeof(BundleOpInfo))};
 
     return new (AllocMarker)
         CallInst(Ty, Func, Args, Bundles, NameStr, AllocMarker, InsertBefore);
   }
 
   static CallInst *Create(FunctionCallee Func, const Twine &NameStr = "",
                           InsertPosition InsertBefore = nullptr) {
     return Create(Func.getFunctionType(), Func.getCallee(), NameStr,
                   InsertBefore);
   }
 
   static CallInst *Create(FunctionCallee Func, ArrayRef<Value *> Args,
                           ArrayRef<OperandBundleDef> Bundles = {},
                           const Twine &NameStr = "",
                           InsertPosition InsertBefore = nullptr) {
     return Create(Func.getFunctionType(), Func.getCallee(), Args, Bundles,
                   NameStr, InsertBefore);
   }
 
   static CallInst *Create(FunctionCallee Func, ArrayRef<Value *> Args,
                           const Twine &NameStr,
                           InsertPosition InsertBefore = nullptr) {
     return Create(Func.getFunctionType(), Func.getCallee(), Args, NameStr,
                   InsertBefore);
   }
 
   /// Create a clone of \p CI with a different set of operand bundles and
   /// insert it before \p InsertBefore.
   ///
   /// The returned call instruction is identical \p CI in every way except that
   /// the operand bundles for the new instruction are set to the operand bundles
   /// in \p Bundles.
   static CallInst *Create(CallInst *CI, ArrayRef<OperandBundleDef> Bundles,
                           InsertPosition InsertPt = nullptr);
 
   // Note that 'musttail' implies 'tail'.
   enum TailCallKind : unsigned {
     TCK_None = 0,
     TCK_Tail = 1,
     TCK_MustTail = 2,
     TCK_NoTail = 3,
     TCK_LAST = TCK_NoTail
   };
 
   using TailCallKindField = Bitfield::Element<TailCallKind, 0, 2, TCK_LAST>;
   static_assert(
       Bitfield::areContiguous<TailCallKindField, CallBase::CallingConvField>(),
       "Bitfields must be contiguous");
 
   TailCallKind getTailCallKind() const {
     return getSubclassData<TailCallKindField>();
   }
 
   bool isTailCall() const {
     TailCallKind Kind = getTailCallKind();
     return Kind == TCK_Tail || Kind == TCK_MustTail;
   }
 
   bool isMustTailCall() const { return getTailCallKind() == TCK_MustTail; }
 
   bool isNoTailCall() const { return getTailCallKind() == TCK_NoTail; }
 
   void setTailCallKind(TailCallKind TCK) {
     setSubclassData<TailCallKindField>(TCK);
   }
 
   void setTailCall(bool IsTc = true) {
     setTailCallKind(IsTc ? TCK_Tail : TCK_None);
   }
 
   /// Return true if the call can return twice
   bool canReturnTwice() const { return hasFnAttr(Attribute::ReturnsTwice); }
   void setCanReturnTwice() { addFnAttr(Attribute::ReturnsTwice); }
 
   /// Return true if the call is for a noreturn trap intrinsic.
   bool isNonContinuableTrap() const {
     switch (getIntrinsicID()) {
     case Intrinsic::trap:
     case Intrinsic::ubsantrap:
       return !hasFnAttr("trap-func-name");
     default:
       return false;
     }
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::Call;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
   /// Updates profile metadata by scaling it by \p S / \p T.
   void updateProfWeight(uint64_t S, uint64_t T);
 
 private:
   // Shadow Instruction::setInstructionSubclassData with a private forwarding
   // method so that subclasses cannot accidentally use it.
   template <typename Bitfield>
   void setSubclassData(typename Bitfield::Type Value) {
     Instruction::setSubclassData<Bitfield>(Value);
   }
 };
 
 CallInst::CallInst(FunctionType *Ty, Value *Func, ArrayRef<Value *> Args,
                    ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr,
                    AllocInfo AllocInfo, InsertPosition InsertBefore)
     : CallBase(Ty->getReturnType(), Instruction::Call, AllocInfo,
                InsertBefore) {
   assert(AllocInfo.NumOps ==
          unsigned(Args.size() + CountBundleInputs(Bundles) + 1));
   init(Ty, Func, Args, Bundles, NameStr);
 }
 
 //===----------------------------------------------------------------------===//
 //                               SelectInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents the LLVM 'select' instruction.
 ///
 class SelectInst : public Instruction {
   constexpr static IntrusiveOperandsAllocMarker AllocMarker{3};
 
   SelectInst(Value *C, Value *S1, Value *S2, const Twine &NameStr,
              InsertPosition InsertBefore)
       : Instruction(S1->getType(), Instruction::Select, AllocMarker,
                     InsertBefore) {
     init(C, S1, S2);
     setName(NameStr);
   }
 
   void init(Value *C, Value *S1, Value *S2) {
     assert(!areInvalidOperands(C, S1, S2) && "Invalid operands for select");
     Op<0>() = C;
     Op<1>() = S1;
     Op<2>() = S2;
   }
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   SelectInst *cloneImpl() const;
 
 public:
   static SelectInst *Create(Value *C, Value *S1, Value *S2,
                             const Twine &NameStr = "",
                             InsertPosition InsertBefore = nullptr,
                             Instruction *MDFrom = nullptr) {
     SelectInst *Sel =
         new (AllocMarker) SelectInst(C, S1, S2, NameStr, InsertBefore);
     if (MDFrom)
       Sel->copyMetadata(*MDFrom);
     return Sel;
   }
 
   const Value *getCondition() const { return Op<0>(); }
   const Value *getTrueValue() const { return Op<1>(); }
   const Value *getFalseValue() const { return Op<2>(); }
   Value *getCondition() { return Op<0>(); }
   Value *getTrueValue() { return Op<1>(); }
   Value *getFalseValue() { return Op<2>(); }
 
   void setCondition(Value *V) { Op<0>() = V; }
   void setTrueValue(Value *V) { Op<1>() = V; }
   void setFalseValue(Value *V) { Op<2>() = V; }
 
   /// Swap the true and false values of the select instruction.
   /// This doesn't swap prof metadata.
   void swapValues() { Op<1>().swap(Op<2>()); }
 
   /// Return a string if the specified operands are invalid
   /// for a select operation, otherwise return null.
   static const char *areInvalidOperands(Value *Cond, Value *True, Value *False);
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   OtherOps getOpcode() const {
     return static_cast<OtherOps>(Instruction::getOpcode());
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::Select;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 template <>
 struct OperandTraits<SelectInst> : public FixedNumOperandTraits<SelectInst, 3> {
 };
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(SelectInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                                VAArgInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents the va_arg llvm instruction, which returns
 /// an argument of the specified type given a va_list and increments that list
 ///
 class VAArgInst : public UnaryInstruction {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   VAArgInst *cloneImpl() const;
 
 public:
   VAArgInst(Value *List, Type *Ty, const Twine &NameStr = "",
             InsertPosition InsertBefore = nullptr)
       : UnaryInstruction(Ty, VAArg, List, InsertBefore) {
     setName(NameStr);
   }
 
   Value *getPointerOperand() { return getOperand(0); }
   const Value *getPointerOperand() const { return getOperand(0); }
   static unsigned getPointerOperandIndex() { return 0U; }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == VAArg;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                ExtractElementInst Class
 //===----------------------------------------------------------------------===//
 
 /// This instruction extracts a single (scalar)
 /// element from a VectorType value
 ///
 class ExtractElementInst : public Instruction {
   constexpr static IntrusiveOperandsAllocMarker AllocMarker{2};
 
   ExtractElementInst(Value *Vec, Value *Idx, const Twine &NameStr = "",
                      InsertPosition InsertBefore = nullptr);
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   ExtractElementInst *cloneImpl() const;
 
 public:
   static ExtractElementInst *Create(Value *Vec, Value *Idx,
                                     const Twine &NameStr = "",
                                     InsertPosition InsertBefore = nullptr) {
     return new (AllocMarker)
         ExtractElementInst(Vec, Idx, NameStr, InsertBefore);
   }
 
   /// Return true if an extractelement instruction can be
   /// formed with the specified operands.
   static bool isValidOperands(const Value *Vec, const Value *Idx);
 
   Value *getVectorOperand() { return Op<0>(); }
   Value *getIndexOperand() { return Op<1>(); }
   const Value *getVectorOperand() const { return Op<0>(); }
   const Value *getIndexOperand() const { return Op<1>(); }
 
   VectorType *getVectorOperandType() const {
     return cast<VectorType>(getVectorOperand()->getType());
   }
 
   /// 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->getOpcode() == Instruction::ExtractElement;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 template <>
 struct OperandTraits<ExtractElementInst> :
   public FixedNumOperandTraits<ExtractElementInst, 2> {
 };
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ExtractElementInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                                InsertElementInst Class
 //===----------------------------------------------------------------------===//
 
 /// This instruction inserts a single (scalar)
 /// element into a VectorType value
 ///
 class InsertElementInst : public Instruction {
   constexpr static IntrusiveOperandsAllocMarker AllocMarker{3};
 
   InsertElementInst(Value *Vec, Value *NewElt, Value *Idx,
                     const Twine &NameStr = "",
                     InsertPosition InsertBefore = nullptr);
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   InsertElementInst *cloneImpl() const;
 
 public:
   static InsertElementInst *Create(Value *Vec, Value *NewElt, Value *Idx,
                                    const Twine &NameStr = "",
                                    InsertPosition InsertBefore = nullptr) {
     return new (AllocMarker)
         InsertElementInst(Vec, NewElt, Idx, NameStr, InsertBefore);
   }
 
   /// Return true if an insertelement instruction can be
   /// formed with the specified operands.
   static bool isValidOperands(const Value *Vec, const Value *NewElt,
                               const Value *Idx);
 
   /// Overload to return most specific vector type.
   ///
   VectorType *getType() const {
     return cast<VectorType>(Instruction::getType());
   }
 
   /// 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->getOpcode() == Instruction::InsertElement;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 template <>
 struct OperandTraits<InsertElementInst> :
   public FixedNumOperandTraits<InsertElementInst, 3> {
 };
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(InsertElementInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                           ShuffleVectorInst Class
 //===----------------------------------------------------------------------===//
 
 constexpr int PoisonMaskElem = -1;
 
 /// This instruction constructs a fixed permutation of two
 /// input vectors.
 ///
 /// For each element of the result vector, the shuffle mask selects an element
 /// from one of the input vectors to copy to the result. Non-negative elements
 /// in the mask represent an index into the concatenated pair of input vectors.
 /// PoisonMaskElem (-1) specifies that the result element is poison.
 ///
 /// For scalable vectors, all the elements of the mask must be 0 or -1. This
 /// requirement may be relaxed in the future.
 class ShuffleVectorInst : public Instruction {
   constexpr static IntrusiveOperandsAllocMarker AllocMarker{2};
 
   SmallVector<int, 4> ShuffleMask;
   Constant *ShuffleMaskForBitcode;
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   ShuffleVectorInst *cloneImpl() const;
 
 public:
   ShuffleVectorInst(Value *V1, Value *Mask, const Twine &NameStr = "",
                     InsertPosition InsertBefore = nullptr);
   ShuffleVectorInst(Value *V1, ArrayRef<int> Mask, const Twine &NameStr = "",
                     InsertPosition InsertBefore = nullptr);
   ShuffleVectorInst(Value *V1, Value *V2, Value *Mask,
                     const Twine &NameStr = "",
                     InsertPosition InsertBefore = nullptr);
   ShuffleVectorInst(Value *V1, Value *V2, ArrayRef<int> Mask,
                     const Twine &NameStr = "",
                     InsertPosition InsertBefore = nullptr);
 
   void *operator new(size_t S) { return User::operator new(S, AllocMarker); }
   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,
                               const Value *Mask);
   static bool isValidOperands(const Value *V1, const Value *V2,
                               ArrayRef<int> Mask);
 
   /// Overload to return most specific vector type.
   ///
   VectorType *getType() const {
     return cast<VectorType>(Instruction::getType());
   }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   /// Return the shuffle mask value of this instruction for the given element
   /// index. Return PoisonMaskElem if the element is undef.
   int getMaskValue(unsigned Elt) const { return ShuffleMask[Elt]; }
 
   /// Convert the input shuffle mask operand to a vector of integers. Undefined
   /// elements of the mask are returned as PoisonMaskElem.
   static void getShuffleMask(const Constant *Mask,
                              SmallVectorImpl<int> &Result);
 
   /// Return the mask for this instruction as a vector of integers. Undefined
   /// elements of the mask are returned as PoisonMaskElem.
   void getShuffleMask(SmallVectorImpl<int> &Result) const {
     Result.assign(ShuffleMask.begin(), ShuffleMask.end());
   }
 
   /// Return the mask for this instruction, for use in bitcode.
   ///
   /// TODO: This is temporary until we decide a new bitcode encoding for
   /// shufflevector.
   Constant *getShuffleMaskForBitcode() const { return ShuffleMaskForBitcode; }
 
   static Constant *convertShuffleMaskForBitcode(ArrayRef<int> Mask,
                                                 Type *ResultTy);
 
   void setShuffleMask(ArrayRef<int> Mask);
 
   ArrayRef<int> getShuffleMask() const { return ShuffleMask; }
 
   /// Return true if this shuffle returns a vector with a different number of
   /// elements than its source vectors.
   /// Examples: shufflevector <4 x n> A, <4 x n> B, <1,2,3>
   ///           shufflevector <4 x n> A, <4 x n> B, <1,2,3,4,5>
   bool changesLength() const {
     unsigned NumSourceElts = cast<VectorType>(Op<0>()->getType())
                                  ->getElementCount()
                                  .getKnownMinValue();
     unsigned NumMaskElts = ShuffleMask.size();
     return NumSourceElts != NumMaskElts;
   }
 
   /// Return true if this shuffle returns a vector with a greater number of
   /// elements than its source vectors.
   /// Example: shufflevector <2 x n> A, <2 x n> B, <1,2,3>
   bool increasesLength() const {
     unsigned NumSourceElts = cast<VectorType>(Op<0>()->getType())
                                  ->getElementCount()
                                  .getKnownMinValue();
     unsigned NumMaskElts = ShuffleMask.size();
     return NumSourceElts < NumMaskElts;
   }
 
   /// Return true if this shuffle mask chooses elements from exactly one source
   /// vector.
   /// Example: <7,5,undef,7>
   /// This assumes that vector operands (of length \p NumSrcElts) are the same
   /// length as the mask.
   static bool isSingleSourceMask(ArrayRef<int> Mask, int NumSrcElts);
   static bool isSingleSourceMask(const Constant *Mask, int NumSrcElts) {
     assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.");
     SmallVector<int, 16> MaskAsInts;
     getShuffleMask(Mask, MaskAsInts);
     return isSingleSourceMask(MaskAsInts, NumSrcElts);
   }
 
   /// Return true if this shuffle chooses elements from exactly one source
   /// vector without changing the length of that vector.
   /// Example: shufflevector <4 x n> A, <4 x n> B, <3,0,undef,3>
   /// TODO: Optionally allow length-changing shuffles.
   bool isSingleSource() const {
     return !changesLength() &&
            isSingleSourceMask(ShuffleMask, ShuffleMask.size());
   }
 
   /// Return true if this shuffle mask chooses elements from exactly one source
   /// vector without lane crossings. A shuffle using this mask is not
   /// necessarily a no-op because it may change the number of elements from its
   /// input vectors or it may provide demanded bits knowledge via undef lanes.
   /// Example: <undef,undef,2,3>
   static bool isIdentityMask(ArrayRef<int> Mask, int NumSrcElts);
   static bool isIdentityMask(const Constant *Mask, int NumSrcElts) {
     assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.");
 
     // Not possible to express a shuffle mask for a scalable vector for this
     // case.
     if (isa<ScalableVectorType>(Mask->getType()))
       return false;
 
     SmallVector<int, 16> MaskAsInts;
     getShuffleMask(Mask, MaskAsInts);
     return isIdentityMask(MaskAsInts, NumSrcElts);
   }
 
   /// Return true if this shuffle chooses elements from exactly one source
   /// vector without lane crossings and does not change the number of elements
   /// from its input vectors.
   /// Example: shufflevector <4 x n> A, <4 x n> B, <4,undef,6,undef>
   bool isIdentity() const {
     // Not possible to express a shuffle mask for a scalable vector for this
     // case.
     if (isa<ScalableVectorType>(getType()))
       return false;
 
     return !changesLength() && isIdentityMask(ShuffleMask, ShuffleMask.size());
   }
 
   /// Return true if this shuffle lengthens exactly one source vector with
   /// undefs in the high elements.
   bool isIdentityWithPadding() const;
 
   /// Return true if this shuffle extracts the first N elements of exactly one
   /// source vector.
   bool isIdentityWithExtract() const;
 
   /// Return true if this shuffle concatenates its 2 source vectors. This
   /// returns false if either input is undefined. In that case, the shuffle is
   /// is better classified as an identity with padding operation.
   bool isConcat() const;
 
   /// Return true if this shuffle mask chooses elements from its source vectors
   /// without lane crossings. A shuffle using this mask would be
   /// equivalent to a vector select with a constant condition operand.
   /// Example: <4,1,6,undef>
   /// This returns false if the mask does not choose from both input vectors.
   /// In that case, the shuffle is better classified as an identity shuffle.
   /// This assumes that vector operands are the same length as the mask
   /// (a length-changing shuffle can never be equivalent to a vector select).
   static bool isSelectMask(ArrayRef<int> Mask, int NumSrcElts);
   static bool isSelectMask(const Constant *Mask, int NumSrcElts) {
     assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.");
     SmallVector<int, 16> MaskAsInts;
     getShuffleMask(Mask, MaskAsInts);
     return isSelectMask(MaskAsInts, NumSrcElts);
   }
 
   /// Return true if this shuffle chooses elements from its source vectors
   /// without lane crossings and all operands have the same number of elements.
   /// In other words, this shuffle is equivalent to a vector select with a
   /// constant condition operand.
   /// Example: shufflevector <4 x n> A, <4 x n> B, <undef,1,6,3>
   /// This returns false if the mask does not choose from both input vectors.
   /// In that case, the shuffle is better classified as an identity shuffle.
   /// TODO: Optionally allow length-changing shuffles.
   bool isSelect() const {
     return !changesLength() && isSelectMask(ShuffleMask, ShuffleMask.size());
   }
 
   /// Return true if this shuffle mask swaps the order of elements from exactly
   /// one source vector.
   /// Example: <7,6,undef,4>
   /// This assumes that vector operands (of length \p NumSrcElts) are the same
   /// length as the mask.
   static bool isReverseMask(ArrayRef<int> Mask, int NumSrcElts);
   static bool isReverseMask(const Constant *Mask, int NumSrcElts) {
     assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.");
     SmallVector<int, 16> MaskAsInts;
     getShuffleMask(Mask, MaskAsInts);
     return isReverseMask(MaskAsInts, NumSrcElts);
   }
 
   /// Return true if this shuffle swaps the order of elements from exactly
   /// one source vector.
   /// Example: shufflevector <4 x n> A, <4 x n> B, <3,undef,1,undef>
   /// TODO: Optionally allow length-changing shuffles.
   bool isReverse() const {
     return !changesLength() && isReverseMask(ShuffleMask, ShuffleMask.size());
   }
 
   /// Return true if this shuffle mask chooses all elements with the same value
   /// as the first element of exactly one source vector.
   /// Example: <4,undef,undef,4>
   /// This assumes that vector operands (of length \p NumSrcElts) are the same
   /// length as the mask.
   static bool isZeroEltSplatMask(ArrayRef<int> Mask, int NumSrcElts);
   static bool isZeroEltSplatMask(const Constant *Mask, int NumSrcElts) {
     assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.");
     SmallVector<int, 16> MaskAsInts;
     getShuffleMask(Mask, MaskAsInts);
     return isZeroEltSplatMask(MaskAsInts, NumSrcElts);
   }
 
   /// Return true if all elements of this shuffle are the same value as the
   /// first element of exactly one source vector without changing the length
   /// of that vector.
   /// Example: shufflevector <4 x n> A, <4 x n> B, <undef,0,undef,0>
   /// TODO: Optionally allow length-changing shuffles.
   /// TODO: Optionally allow splats from other elements.
   bool isZeroEltSplat() const {
     return !changesLength() &&
            isZeroEltSplatMask(ShuffleMask, ShuffleMask.size());
   }
 
   /// Return true if this shuffle mask is a transpose mask.
   /// Transpose vector masks transpose a 2xn matrix. They read corresponding
   /// even- or odd-numbered vector elements from two n-dimensional source
   /// vectors and write each result into consecutive elements of an
   /// n-dimensional destination vector. Two shuffles are necessary to complete
   /// the transpose, one for the even elements and another for the odd elements.
   /// This description closely follows how the TRN1 and TRN2 AArch64
   /// instructions operate.
   ///
   /// For example, a simple 2x2 matrix can be transposed with:
   ///
   ///   ; Original matrix
   ///   m0 = < a, b >
   ///   m1 = < c, d >
   ///
   ///   ; Transposed matrix
   ///   t0 = < a, c > = shufflevector m0, m1, < 0, 2 >
   ///   t1 = < b, d > = shufflevector m0, m1, < 1, 3 >
   ///
   /// For matrices having greater than n columns, the resulting nx2 transposed
   /// matrix is stored in two result vectors such that one vector contains
   /// interleaved elements from all the even-numbered rows and the other vector
   /// contains interleaved elements from all the odd-numbered rows. For example,
   /// a 2x4 matrix can be transposed with:
   ///
   ///   ; Original matrix
   ///   m0 = < a, b, c, d >
   ///   m1 = < e, f, g, h >
   ///
   ///   ; Transposed matrix
   ///   t0 = < a, e, c, g > = shufflevector m0, m1 < 0, 4, 2, 6 >
   ///   t1 = < b, f, d, h > = shufflevector m0, m1 < 1, 5, 3, 7 >
   static bool isTransposeMask(ArrayRef<int> Mask, int NumSrcElts);
   static bool isTransposeMask(const Constant *Mask, int NumSrcElts) {
     assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.");
     SmallVector<int, 16> MaskAsInts;
     getShuffleMask(Mask, MaskAsInts);
     return isTransposeMask(MaskAsInts, NumSrcElts);
   }
 
   /// Return true if this shuffle transposes the elements of its inputs without
   /// changing the length of the vectors. This operation may also be known as a
   /// merge or interleave. See the description for isTransposeMask() for the
   /// exact specification.
   /// Example: shufflevector <4 x n> A, <4 x n> B, <0,4,2,6>
   bool isTranspose() const {
     return !changesLength() && isTransposeMask(ShuffleMask, ShuffleMask.size());
   }
 
   /// Return true if this shuffle mask is a splice mask, concatenating the two
   /// inputs together and then extracts an original width vector starting from
   /// the splice index.
   /// Example: shufflevector <4 x n> A, <4 x n> B, <1,2,3,4>
   /// This assumes that vector operands (of length \p NumSrcElts) are the same
   /// length as the mask.
   static bool isSpliceMask(ArrayRef<int> Mask, int NumSrcElts, int &Index);
   static bool isSpliceMask(const Constant *Mask, int NumSrcElts, int &Index) {
     assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.");
     SmallVector<int, 16> MaskAsInts;
     getShuffleMask(Mask, MaskAsInts);
     return isSpliceMask(MaskAsInts, NumSrcElts, Index);
   }
 
   /// Return true if this shuffle splices two inputs without changing the length
   /// of the vectors. This operation concatenates the two inputs together and
   /// then extracts an original width vector starting from the splice index.
   /// Example: shufflevector <4 x n> A, <4 x n> B, <1,2,3,4>
   bool isSplice(int &Index) const {
     return !changesLength() &&
            isSpliceMask(ShuffleMask, ShuffleMask.size(), Index);
   }
 
   /// Return true if this shuffle mask is an extract subvector mask.
   /// A valid extract subvector mask returns a smaller vector from a single
   /// source operand. The base extraction index is returned as well.
   static bool isExtractSubvectorMask(ArrayRef<int> Mask, int NumSrcElts,
                                      int &Index);
   static bool isExtractSubvectorMask(const Constant *Mask, int NumSrcElts,
                                      int &Index) {
     assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.");
     // Not possible to express a shuffle mask for a scalable vector for this
     // case.
     if (isa<ScalableVectorType>(Mask->getType()))
       return false;
     SmallVector<int, 16> MaskAsInts;
     getShuffleMask(Mask, MaskAsInts);
     return isExtractSubvectorMask(MaskAsInts, NumSrcElts, Index);
   }
 
   /// Return true if this shuffle mask is an extract subvector mask.
   bool isExtractSubvectorMask(int &Index) const {
     // Not possible to express a shuffle mask for a scalable vector for this
     // case.
     if (isa<ScalableVectorType>(getType()))
       return false;
 
     int NumSrcElts =
         cast<FixedVectorType>(Op<0>()->getType())->getNumElements();
     return isExtractSubvectorMask(ShuffleMask, NumSrcElts, Index);
   }
 
   /// Return true if this shuffle mask is an insert subvector mask.
   /// A valid insert subvector mask inserts the lowest elements of a second
   /// source operand into an in-place first source operand.
   /// Both the sub vector width and the insertion index is returned.
   static bool isInsertSubvectorMask(ArrayRef<int> Mask, int NumSrcElts,
                                     int &NumSubElts, int &Index);
   static bool isInsertSubvectorMask(const Constant *Mask, int NumSrcElts,
                                     int &NumSubElts, int &Index) {
     assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.");
     // Not possible to express a shuffle mask for a scalable vector for this
     // case.
     if (isa<ScalableVectorType>(Mask->getType()))
       return false;
     SmallVector<int, 16> MaskAsInts;
     getShuffleMask(Mask, MaskAsInts);
     return isInsertSubvectorMask(MaskAsInts, NumSrcElts, NumSubElts, Index);
   }
 
   /// Return true if this shuffle mask is an insert subvector mask.
   bool isInsertSubvectorMask(int &NumSubElts, int &Index) const {
     // Not possible to express a shuffle mask for a scalable vector for this
     // case.
     if (isa<ScalableVectorType>(getType()))
       return false;
 
     int NumSrcElts =
         cast<FixedVectorType>(Op<0>()->getType())->getNumElements();
     return isInsertSubvectorMask(ShuffleMask, NumSrcElts, NumSubElts, Index);
   }
 
   /// Return true if this shuffle mask replicates each of the \p VF elements
   /// in a vector \p ReplicationFactor times.
   /// For example, the mask for \p ReplicationFactor=3 and \p VF=4 is:
   ///   <0,0,0,1,1,1,2,2,2,3,3,3>
   static bool isReplicationMask(ArrayRef<int> Mask, int &ReplicationFactor,
                                 int &VF);
   static bool isReplicationMask(const Constant *Mask, int &ReplicationFactor,
                                 int &VF) {
     assert(Mask->getType()->isVectorTy() && "Shuffle needs vector constant.");
     // Not possible to express a shuffle mask for a scalable vector for this
     // case.
     if (isa<ScalableVectorType>(Mask->getType()))
       return false;
     SmallVector<int, 16> MaskAsInts;
     getShuffleMask(Mask, MaskAsInts);
     return isReplicationMask(MaskAsInts, ReplicationFactor, VF);
   }
 
   /// Return true if this shuffle mask is a replication mask.
   bool isReplicationMask(int &ReplicationFactor, int &VF) const;
 
   /// Return true if this shuffle mask represents "clustered" mask of size VF,
   /// i.e. each index between [0..VF) is used exactly once in each submask of
   /// size VF.
   /// For example, the mask for \p VF=4 is:
   /// 0, 1, 2, 3, 3, 2, 0, 1 - "clustered", because each submask of size 4
   /// (0,1,2,3 and 3,2,0,1) uses indices [0..VF) exactly one time.
   /// 0, 1, 2, 3, 3, 3, 1, 0 - not "clustered", because
   ///                          element 3 is used twice in the second submask
   ///                          (3,3,1,0) and index 2 is not used at all.
   static bool isOneUseSingleSourceMask(ArrayRef<int> Mask, int VF);
 
   /// Return true if this shuffle mask is a one-use-single-source("clustered")
   /// mask.
   bool isOneUseSingleSourceMask(int VF) const;
 
   /// Change values in a shuffle permute mask assuming the two vector operands
   /// of length InVecNumElts have swapped position.
   static void commuteShuffleMask(MutableArrayRef<int> Mask,
                                  unsigned InVecNumElts) {
     for (int &Idx : Mask) {
       if (Idx == -1)
         continue;
       Idx = Idx < (int)InVecNumElts ? Idx + InVecNumElts : Idx - InVecNumElts;
       assert(Idx >= 0 && Idx < (int)InVecNumElts * 2 &&
              "shufflevector mask index out of range");
     }
   }
 
   /// Return if this shuffle interleaves its two input vectors together.
   bool isInterleave(unsigned Factor);
 
   /// Return true if the mask interleaves one or more input vectors together.
   ///
   /// I.e. <0, LaneLen, ... , LaneLen*(Factor - 1), 1, LaneLen + 1, ...>
   /// E.g. For a Factor of 2 (LaneLen=4):
   ///   <0, 4, 1, 5, 2, 6, 3, 7>
   /// E.g. For a Factor of 3 (LaneLen=4):
   ///   <4, 0, 9, 5, 1, 10, 6, 2, 11, 7, 3, 12>
   /// E.g. For a Factor of 4 (LaneLen=2):
   ///   <0, 2, 6, 4, 1, 3, 7, 5>
   ///
   /// NumInputElts is the total number of elements in the input vectors.
   ///
   /// StartIndexes are the first indexes of each vector being interleaved,
   /// substituting any indexes that were undef
   /// E.g. <4, -1, 2, 5, 1, 3> (Factor=3): StartIndexes=<4, 0, 2>
   ///
   /// Note that this does not check if the input vectors are consecutive:
   /// It will return true for masks such as
   /// <0, 4, 6, 1, 5, 7> (Factor=3, LaneLen=2)
   static bool isInterleaveMask(ArrayRef<int> Mask, unsigned Factor,
                                unsigned NumInputElts,
                                SmallVectorImpl<unsigned> &StartIndexes);
   static bool isInterleaveMask(ArrayRef<int> Mask, unsigned Factor,
                                unsigned NumInputElts) {
     SmallVector<unsigned, 8> StartIndexes;
     return isInterleaveMask(Mask, Factor, NumInputElts, StartIndexes);
   }
 
   /// Check if the mask is a DE-interleave mask of the given factor
   /// \p Factor like:
   ///     <Index, Index+Factor, ..., Index+(NumElts-1)*Factor>
   static bool isDeInterleaveMaskOfFactor(ArrayRef<int> Mask, unsigned Factor,
                                          unsigned &Index);
   static bool isDeInterleaveMaskOfFactor(ArrayRef<int> Mask, unsigned Factor) {
     unsigned Unused;
     return isDeInterleaveMaskOfFactor(Mask, Factor, Unused);
   }
 
   /// Checks if the shuffle is a bit rotation of the first operand across
   /// multiple subelements, e.g:
   ///
   /// shuffle <8 x i8> %a, <8 x i8> poison, <8 x i32> <1, 0, 3, 2, 5, 4, 7, 6>
   ///
   /// could be expressed as
   ///
   /// rotl <4 x i16> %a, 8
   ///
   /// If it can be expressed as a rotation, returns the number of subelements to
   /// group by in NumSubElts and the number of bits to rotate left in RotateAmt.
   static bool isBitRotateMask(ArrayRef<int> Mask, unsigned EltSizeInBits,
                               unsigned MinSubElts, unsigned MaxSubElts,
                               unsigned &NumSubElts, unsigned &RotateAmt);
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::ShuffleVector;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 template <>
 struct OperandTraits<ShuffleVectorInst>
     : public FixedNumOperandTraits<ShuffleVectorInst, 2> {};
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ShuffleVectorInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                                ExtractValueInst Class
 //===----------------------------------------------------------------------===//
 
 /// This instruction extracts a struct member or array
 /// element value from an aggregate value.
 ///
 class ExtractValueInst : public UnaryInstruction {
   SmallVector<unsigned, 4> Indices;
 
   ExtractValueInst(const ExtractValueInst &EVI);
 
   /// Constructors - Create a extractvalue instruction with a base aggregate
   /// value and a list of indices. The first and second ctor can optionally
   /// insert before an existing instruction, the third appends the new
   /// instruction to the specified BasicBlock.
   inline ExtractValueInst(Value *Agg, ArrayRef<unsigned> Idxs,
                           const Twine &NameStr, InsertPosition InsertBefore);
 
   void init(ArrayRef<unsigned> Idxs, const Twine &NameStr);
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   ExtractValueInst *cloneImpl() const;
 
 public:
   static ExtractValueInst *Create(Value *Agg, ArrayRef<unsigned> Idxs,
                                   const Twine &NameStr = "",
                                   InsertPosition InsertBefore = nullptr) {
     return new
       ExtractValueInst(Agg, Idxs, NameStr, InsertBefore);
   }
 
   /// Returns the type of the element that would be extracted
   /// with an extractvalue instruction with the specified parameters.
   ///
   /// Null is returned if the indices are invalid for the specified type.
   static Type *getIndexedType(Type *Agg, ArrayRef<unsigned> Idxs);
 
   using idx_iterator = const unsigned*;
 
   inline idx_iterator idx_begin() const { return Indices.begin(); }
   inline idx_iterator idx_end()   const { return Indices.end(); }
   inline iterator_range<idx_iterator> indices() const {
     return make_range(idx_begin(), idx_end());
   }
 
   Value *getAggregateOperand() {
     return getOperand(0);
   }
   const Value *getAggregateOperand() const {
     return getOperand(0);
   }
   static unsigned getAggregateOperandIndex() {
     return 0U;                      // get index for modifying correct operand
   }
 
   ArrayRef<unsigned> getIndices() const {
     return Indices;
   }
 
   unsigned getNumIndices() const {
     return (unsigned)Indices.size();
   }
 
   bool hasIndices() const {
     return true;
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::ExtractValue;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 ExtractValueInst::ExtractValueInst(Value *Agg, ArrayRef<unsigned> Idxs,
                                    const Twine &NameStr,
                                    InsertPosition InsertBefore)
     : UnaryInstruction(checkGEPType(getIndexedType(Agg->getType(), Idxs)),
                        ExtractValue, Agg, InsertBefore) {
   init(Idxs, NameStr);
 }
 
 //===----------------------------------------------------------------------===//
 //                                InsertValueInst Class
 //===----------------------------------------------------------------------===//
 
 /// This instruction inserts a struct field of array element
 /// value into an aggregate value.
 ///
 class InsertValueInst : public Instruction {
   constexpr static IntrusiveOperandsAllocMarker AllocMarker{2};
 
   SmallVector<unsigned, 4> Indices;
 
   InsertValueInst(const InsertValueInst &IVI);
 
   /// Constructors - Create a insertvalue instruction with a base aggregate
   /// value, a value to insert, and a list of indices. The first and second ctor
   /// can optionally insert before an existing instruction, the third appends
   /// the new instruction to the specified BasicBlock.
   inline InsertValueInst(Value *Agg, Value *Val, ArrayRef<unsigned> Idxs,
                          const Twine &NameStr, InsertPosition InsertBefore);
 
   /// Constructors - These three constructors are convenience methods because
   /// one and two index insertvalue instructions are so common.
   InsertValueInst(Value *Agg, Value *Val, unsigned Idx,
                   const Twine &NameStr = "",
                   InsertPosition InsertBefore = nullptr);
 
   void init(Value *Agg, Value *Val, ArrayRef<unsigned> Idxs,
             const Twine &NameStr);
 
 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, AllocMarker); }
   void operator delete(void *Ptr) { User::operator delete(Ptr); }
 
   static InsertValueInst *Create(Value *Agg, Value *Val,
                                  ArrayRef<unsigned> Idxs,
                                  const Twine &NameStr = "",
                                  InsertPosition InsertBefore = nullptr) {
     return new InsertValueInst(Agg, Val, Idxs, NameStr, InsertBefore);
   }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   using idx_iterator = const unsigned*;
 
   inline idx_iterator idx_begin() const { return Indices.begin(); }
   inline idx_iterator idx_end()   const { return Indices.end(); }
   inline iterator_range<idx_iterator> indices() const {
     return make_range(idx_begin(), idx_end());
   }
 
   Value *getAggregateOperand() {
     return getOperand(0);
   }
   const Value *getAggregateOperand() const {
     return getOperand(0);
   }
   static unsigned getAggregateOperandIndex() {
     return 0U;                      // get index for modifying correct operand
   }
 
   Value *getInsertedValueOperand() {
     return getOperand(1);
   }
   const Value *getInsertedValueOperand() const {
     return getOperand(1);
   }
   static unsigned getInsertedValueOperandIndex() {
     return 1U;                      // get index for modifying correct operand
   }
 
   ArrayRef<unsigned> getIndices() const {
     return Indices;
   }
 
   unsigned getNumIndices() const {
     return (unsigned)Indices.size();
   }
 
   bool hasIndices() const {
     return true;
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::InsertValue;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 template <>
 struct OperandTraits<InsertValueInst> :
   public FixedNumOperandTraits<InsertValueInst, 2> {
 };
 
 InsertValueInst::InsertValueInst(Value *Agg, Value *Val,
                                  ArrayRef<unsigned> Idxs, const Twine &NameStr,
                                  InsertPosition InsertBefore)
     : Instruction(Agg->getType(), InsertValue, AllocMarker, InsertBefore) {
   init(Agg, Val, Idxs, NameStr);
 }
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(InsertValueInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                               PHINode Class
 //===----------------------------------------------------------------------===//
 
 // PHINode - The PHINode class is used to represent the magical mystical PHI
 // node, that can not exist in nature, but can be synthesized in a computer
 // scientist's overactive imagination.
 //
 class PHINode : public Instruction {
   constexpr static HungOffOperandsAllocMarker AllocMarker{};
 
   /// The number of operands actually allocated.  NumOperands is
   /// the number actually in use.
   unsigned ReservedSpace;
 
   PHINode(const PHINode &PN);
 
   explicit PHINode(Type *Ty, unsigned NumReservedValues,
                    const Twine &NameStr = "",
                    InsertPosition InsertBefore = nullptr)
       : Instruction(Ty, Instruction::PHI, AllocMarker, InsertBefore),
         ReservedSpace(NumReservedValues) {
     assert(!Ty->isTokenTy() && "PHI nodes cannot have token type!");
     setName(NameStr);
     allocHungoffUses(ReservedSpace);
   }
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   PHINode *cloneImpl() const;
 
   // allocHungoffUses - this is more complicated than the generic
   // User::allocHungoffUses, because we have to allocate Uses for the incoming
   // values and pointers to the incoming blocks, all in one allocation.
   void allocHungoffUses(unsigned N) {
     User::allocHungoffUses(N, /* IsPhi */ true);
   }
 
 public:
   /// Constructors - NumReservedValues is a hint for the number of incoming
   /// edges that this phi node will have (use 0 if you really have no idea).
   static PHINode *Create(Type *Ty, unsigned NumReservedValues,
                          const Twine &NameStr = "",
                          InsertPosition InsertBefore = nullptr) {
     return new (AllocMarker)
         PHINode(Ty, NumReservedValues, NameStr, InsertBefore);
   }
 
   /// Provide fast operand accessors
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   // Block iterator interface. This provides access to the list of incoming
   // basic blocks, which parallels the list of incoming values.
   // Please note that we are not providing non-const iterators for blocks to
   // force all updates go through an interface function.
 
   using block_iterator = BasicBlock **;
   using const_block_iterator = BasicBlock * const *;
 
   const_block_iterator block_begin() const {
     return reinterpret_cast<const_block_iterator>(op_begin() + ReservedSpace);
   }
 
   const_block_iterator block_end() const {
     return block_begin() + getNumOperands();
   }
 
   iterator_range<const_block_iterator> blocks() const {
     return make_range(block_begin(), block_end());
   }
 
   op_range incoming_values() { return operands(); }
 
   const_op_range incoming_values() const { return operands(); }
 
   /// Return the number of incoming edges
   ///
   unsigned getNumIncomingValues() const { return getNumOperands(); }
 
   /// Return incoming value number x
   ///
   Value *getIncomingValue(unsigned i) const {
     return getOperand(i);
   }
   void setIncomingValue(unsigned i, Value *V) {
     assert(V && "PHI node got a null value!");
     assert(getType() == V->getType() &&
            "All operands to PHI node must be the same type as the PHI node!");
     setOperand(i, V);
   }
 
   static unsigned getOperandNumForIncomingValue(unsigned i) {
     return i;
   }
 
   static unsigned getIncomingValueNumForOperand(unsigned i) {
     return i;
   }
 
   /// Return incoming basic block number @p i.
   ///
   BasicBlock *getIncomingBlock(unsigned i) const {
     return block_begin()[i];
   }
 
   /// Return incoming basic block corresponding
   /// to an operand of the PHI.
   ///
   BasicBlock *getIncomingBlock(const Use &U) const {
     assert(this == U.getUser() && "Iterator doesn't point to PHI's Uses?");
     return getIncomingBlock(unsigned(&U - op_begin()));
   }
 
   /// Return incoming basic block corresponding
   /// to value use iterator.
   ///
   BasicBlock *getIncomingBlock(Value::const_user_iterator I) const {
     return getIncomingBlock(I.getUse());
   }
 
   void setIncomingBlock(unsigned i, BasicBlock *BB) {
     const_cast<block_iterator>(block_begin())[i] = BB;
   }
 
   /// Copies the basic blocks from \p BBRange to the incoming basic block list
   /// of this PHINode, starting at \p ToIdx.
   void copyIncomingBlocks(iterator_range<const_block_iterator> BBRange,
                           uint32_t ToIdx = 0) {
     copy(BBRange, const_cast<block_iterator>(block_begin()) + ToIdx);
   }
 
   /// Replace every incoming basic block \p Old to basic block \p New.
   void replaceIncomingBlockWith(const BasicBlock *Old, BasicBlock *New) {
     assert(New && Old && "PHI node got a null basic block!");
     for (unsigned Op = 0, NumOps = getNumOperands(); Op != NumOps; ++Op)
       if (getIncomingBlock(Op) == Old)
         setIncomingBlock(Op, New);
   }
 
   /// Add an incoming value to the end of the PHI list
   ///
   void addIncoming(Value *V, BasicBlock *BB) {
     if (getNumOperands() == ReservedSpace)
       growOperands();  // Get more space!
     // Initialize some new operands.
     setNumHungOffUseOperands(getNumOperands() + 1);
     setIncomingValue(getNumOperands() - 1, V);
     setIncomingBlock(getNumOperands() - 1, BB);
   }
 
   /// Remove an incoming value.  This is useful if a
   /// predecessor basic block is deleted.  The value removed is returned.
   ///
   /// If the last incoming value for a PHI node is removed (and DeletePHIIfEmpty
   /// is true), the PHI node is destroyed and any uses of it are replaced with
   /// dummy values.  The only time there should be zero incoming values to a PHI
   /// node is when the block is dead, so this strategy is sound.
   ///
   Value *removeIncomingValue(unsigned Idx, bool DeletePHIIfEmpty = true);
 
   Value *removeIncomingValue(const BasicBlock *BB, bool DeletePHIIfEmpty=true) {
     int Idx = getBasicBlockIndex(BB);
     assert(Idx >= 0 && "Invalid basic block argument to remove!");
     return removeIncomingValue(Idx, DeletePHIIfEmpty);
   }
 
   /// Remove all incoming values for which the predicate returns true.
   /// The predicate accepts the incoming value index.
   void removeIncomingValueIf(function_ref<bool(unsigned)> Predicate,
                              bool DeletePHIIfEmpty = true);
 
   /// Return the first index of the specified basic
   /// block in the value list for this PHI.  Returns -1 if no instance.
   ///
   int getBasicBlockIndex(const BasicBlock *BB) const {
     for (unsigned i = 0, e = getNumOperands(); i != e; ++i)
       if (block_begin()[i] == BB)
         return i;
     return -1;
   }
 
   Value *getIncomingValueForBlock(const BasicBlock *BB) const {
     int Idx = getBasicBlockIndex(BB);
     assert(Idx >= 0 && "Invalid basic block argument!");
     return getIncomingValue(Idx);
   }
 
   /// Set every incoming value(s) for block \p BB to \p V.
   void setIncomingValueForBlock(const BasicBlock *BB, Value *V) {
     assert(BB && "PHI node got a null basic block!");
     bool Found = false;
     for (unsigned Op = 0, NumOps = getNumOperands(); Op != NumOps; ++Op)
       if (getIncomingBlock(Op) == BB) {
         Found = true;
         setIncomingValue(Op, V);
       }
     (void)Found;
     assert(Found && "Invalid basic block argument to set!");
   }
 
   /// If the specified PHI node always merges together the
   /// same value, return the value, otherwise return null.
   Value *hasConstantValue() const;
 
   /// Whether the specified PHI node always merges
   /// together the same value, assuming undefs are equal to a unique
   /// non-undef value.
   bool hasConstantOrUndefValue() const;
 
   /// If the PHI node is complete which means all of its parent's predecessors
   /// have incoming value in this PHI, return true, otherwise return false.
   bool isComplete() const {
     return llvm::all_of(predecessors(getParent()),
                         [this](const BasicBlock *Pred) {
                           return getBasicBlockIndex(Pred) >= 0;
                         });
   }
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::PHI;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   void growOperands();
 };
 
 template <> struct OperandTraits<PHINode> : public HungoffOperandTraits {};
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(PHINode, Value)
 
 //===----------------------------------------------------------------------===//
 //                           LandingPadInst Class
 //===----------------------------------------------------------------------===//
 
 //===---------------------------------------------------------------------------
 /// The landingpad instruction holds all of the information
 /// necessary to generate correct exception handling. The landingpad instruction
 /// cannot be moved from the top of a landing pad block, which itself is
 /// accessible only from the 'unwind' edge of an invoke. This uses the
 /// SubclassData field in Value to store whether or not the landingpad is a
 /// cleanup.
 ///
 class LandingPadInst : public Instruction {
   using CleanupField = BoolBitfieldElementT<0>;
 
   constexpr static HungOffOperandsAllocMarker AllocMarker{};
 
   /// The number of operands actually allocated.  NumOperands is
   /// the number actually in use.
   unsigned ReservedSpace;
 
   LandingPadInst(const LandingPadInst &LP);
 
 public:
   enum ClauseType { Catch, Filter };
 
 private:
   explicit LandingPadInst(Type *RetTy, unsigned NumReservedValues,
                           const Twine &NameStr, InsertPosition InsertBefore);
 
   // Allocate space for exactly zero operands.
   void *operator new(size_t S) { return User::operator new(S, AllocMarker); }
 
   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 = "",
                                 InsertPosition InsertBefore = nullptr);
 
   /// Provide fast operand accessors
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   /// Return 'true' if this landingpad instruction is a
   /// cleanup. I.e., it should be run when unwinding even if its landing pad
   /// doesn't catch the exception.
   bool isCleanup() const { return getSubclassData<CleanupField>(); }
 
   /// Indicate that this landingpad instruction is a cleanup.
   void setCleanup(bool V) { setSubclassData<CleanupField>(V); }
 
   /// Add a catch or filter clause to the landing pad.
   void addClause(Constant *ClauseVal);
 
   /// Get the value of the clause at index Idx. Use isCatch/isFilter to
   /// determine what type of clause this is.
   Constant *getClause(unsigned Idx) const {
     return cast<Constant>(getOperandList()[Idx]);
   }
 
   /// Return 'true' if the clause and index Idx is a catch clause.
   bool isCatch(unsigned Idx) const {
     return !isa<ArrayType>(getOperandList()[Idx]->getType());
   }
 
   /// Return 'true' if the clause and index Idx is a filter clause.
   bool isFilter(unsigned Idx) const {
     return isa<ArrayType>(getOperandList()[Idx]->getType());
   }
 
   /// Get the number of clauses for this landing pad.
   unsigned getNumClauses() const { return getNumOperands(); }
 
   /// Grow the size of the operand list to accommodate the new
   /// number of clauses.
   void reserveClauses(unsigned Size) { growOperands(Size); }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::LandingPad;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 template <>
 struct OperandTraits<LandingPadInst> : public HungoffOperandTraits {};
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(LandingPadInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                               ReturnInst Class
 //===----------------------------------------------------------------------===//
 
 //===---------------------------------------------------------------------------
 /// Return a value (possibly void), from a function.  Execution
 /// does not continue in this function any longer.
 ///
 class ReturnInst : public Instruction {
   ReturnInst(const ReturnInst &RI, AllocInfo AllocInfo);
 
 private:
   // ReturnInst constructors:
   // ReturnInst()                  - 'ret void' instruction
   // ReturnInst(    null)          - 'ret void' instruction
   // ReturnInst(Value* X)          - 'ret X'    instruction
   // ReturnInst(null, Iterator It) - 'ret void' instruction, insert before I
   // ReturnInst(Value* X, Iterator It) - 'ret X'    instruction, insert before I
   // ReturnInst(    null, Inst *I) - 'ret void' instruction, insert before I
   // ReturnInst(Value* X, Inst *I) - 'ret X'    instruction, insert before I
   // ReturnInst(    null, BB *B)   - 'ret void' instruction, insert @ end of B
   // ReturnInst(Value* X, BB *B)   - 'ret X'    instruction, insert @ end of B
   //
   // NOTE: If the Value* passed is of type void then the constructor behaves as
   // if it was passed NULL.
   explicit ReturnInst(LLVMContext &C, Value *retVal, AllocInfo AllocInfo,
                       InsertPosition InsertBefore);
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   ReturnInst *cloneImpl() const;
 
 public:
   static ReturnInst *Create(LLVMContext &C, Value *retVal = nullptr,
                             InsertPosition InsertBefore = nullptr) {
     IntrusiveOperandsAllocMarker AllocMarker{retVal ? 1U : 0U};
     return new (AllocMarker) ReturnInst(C, retVal, AllocMarker, InsertBefore);
   }
 
   static ReturnInst *Create(LLVMContext &C, BasicBlock *InsertAtEnd) {
     IntrusiveOperandsAllocMarker AllocMarker{0};
     return new (AllocMarker) ReturnInst(C, nullptr, AllocMarker, InsertAtEnd);
   }
 
   /// Provide fast operand accessors
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   /// Convenience accessor. Returns null if there is no return value.
   Value *getReturnValue() const {
     return getNumOperands() != 0 ? getOperand(0) : nullptr;
   }
 
   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::Ret);
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   BasicBlock *getSuccessor(unsigned idx) const {
     llvm_unreachable("ReturnInst has no successors!");
   }
 
   void setSuccessor(unsigned idx, BasicBlock *B) {
     llvm_unreachable("ReturnInst has no successors!");
   }
 };
 
 template <>
 struct OperandTraits<ReturnInst> : public VariadicOperandTraits<ReturnInst> {};
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ReturnInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                               BranchInst Class
 //===----------------------------------------------------------------------===//
 
 //===---------------------------------------------------------------------------
 /// Conditional or Unconditional Branch instruction.
 ///
 class BranchInst : public Instruction {
   /// Ops list - Branches are strange.  The operands are ordered:
   ///  [Cond, FalseDest,] TrueDest.  This makes some accessors faster because
   /// they don't have to check for cond/uncond branchness. These are mostly
   /// accessed relative from op_end().
   BranchInst(const BranchInst &BI, AllocInfo AllocInfo);
   // BranchInst constructors (where {B, T, F} are blocks, and C is a condition):
   // BranchInst(BB *B)                           - 'br B'
   // BranchInst(BB* T, BB *F, Value *C)          - 'br C, T, F'
   // BranchInst(BB* B, Iter It)                  - 'br B'        insert before I
   // BranchInst(BB* T, BB *F, Value *C, Iter It) - 'br C, T, F', insert before I
   // BranchInst(BB* B, Inst *I)                  - 'br B'        insert before I
   // BranchInst(BB* T, BB *F, Value *C, Inst *I) - 'br C, T, F', insert before I
   // BranchInst(BB* B, BB *I)                    - 'br B'        insert at end
   // BranchInst(BB* T, BB *F, Value *C, BB *I)   - 'br C, T, F', insert at end
   explicit BranchInst(BasicBlock *IfTrue, AllocInfo AllocInfo,
                       InsertPosition InsertBefore);
   BranchInst(BasicBlock *IfTrue, BasicBlock *IfFalse, Value *Cond,
              AllocInfo AllocInfo, InsertPosition InsertBefore);
 
   void AssertOK();
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   BranchInst *cloneImpl() const;
 
 public:
   /// Iterator type that casts an operand to a basic block.
   ///
   /// This only makes sense because the successors are stored as adjacent
   /// operands for branch instructions.
   struct succ_op_iterator
       : iterator_adaptor_base<succ_op_iterator, value_op_iterator,
                               std::random_access_iterator_tag, BasicBlock *,
                               ptrdiff_t, BasicBlock *, BasicBlock *> {
     explicit succ_op_iterator(value_op_iterator I) : iterator_adaptor_base(I) {}
 
     BasicBlock *operator*() const { return cast<BasicBlock>(*I); }
     BasicBlock *operator->() const { return operator*(); }
   };
 
   /// The const version of `succ_op_iterator`.
   struct const_succ_op_iterator
       : iterator_adaptor_base<const_succ_op_iterator, const_value_op_iterator,
                               std::random_access_iterator_tag,
                               const BasicBlock *, ptrdiff_t, const BasicBlock *,
                               const BasicBlock *> {
     explicit const_succ_op_iterator(const_value_op_iterator I)
         : iterator_adaptor_base(I) {}
 
     const BasicBlock *operator*() const { return cast<BasicBlock>(*I); }
     const BasicBlock *operator->() const { return operator*(); }
   };
 
   static BranchInst *Create(BasicBlock *IfTrue,
                             InsertPosition InsertBefore = nullptr) {
     IntrusiveOperandsAllocMarker AllocMarker{1};
     return new (AllocMarker) BranchInst(IfTrue, AllocMarker, InsertBefore);
   }
 
   static BranchInst *Create(BasicBlock *IfTrue, BasicBlock *IfFalse,
                             Value *Cond,
                             InsertPosition InsertBefore = nullptr) {
     IntrusiveOperandsAllocMarker AllocMarker{3};
     return new (AllocMarker)
         BranchInst(IfTrue, IfFalse, Cond, AllocMarker, InsertBefore);
   }
 
   /// Transparently provide more efficient getOperand methods.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   bool isUnconditional() const { return getNumOperands() == 1; }
   bool isConditional()   const { return getNumOperands() == 3; }
 
   Value *getCondition() const {
     assert(isConditional() && "Cannot get condition of an uncond branch!");
     return Op<-3>();
   }
 
   void setCondition(Value *V) {
     assert(isConditional() && "Cannot set condition of unconditional branch!");
     Op<-3>() = V;
   }
 
   unsigned getNumSuccessors() const { return 1+isConditional(); }
 
   BasicBlock *getSuccessor(unsigned i) const {
     assert(i < getNumSuccessors() && "Successor # out of range for Branch!");
     return cast_or_null<BasicBlock>((&Op<-1>() - i)->get());
   }
 
   void setSuccessor(unsigned idx, BasicBlock *NewSucc) {
     assert(idx < getNumSuccessors() && "Successor # out of range for Branch!");
     *(&Op<-1>() - idx) = NewSucc;
   }
 
   /// Swap the successors of this branch instruction.
   ///
   /// Swaps the successors of the branch instruction. This also swaps any
   /// branch weight metadata associated with the instruction so that it
   /// continues to map correctly to each operand.
   void swapSuccessors();
 
   iterator_range<succ_op_iterator> successors() {
     return make_range(
         succ_op_iterator(std::next(value_op_begin(), isConditional() ? 1 : 0)),
         succ_op_iterator(value_op_end()));
   }
 
   iterator_range<const_succ_op_iterator> successors() const {
     return make_range(const_succ_op_iterator(
                           std::next(value_op_begin(), isConditional() ? 1 : 0)),
                       const_succ_op_iterator(value_op_end()));
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return (I->getOpcode() == Instruction::Br);
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 template <>
 struct OperandTraits<BranchInst> : public VariadicOperandTraits<BranchInst> {};
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(BranchInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                               SwitchInst Class
 //===----------------------------------------------------------------------===//
 
 //===---------------------------------------------------------------------------
 /// Multiway switch
 ///
 class SwitchInst : public Instruction {
   constexpr static HungOffOperandsAllocMarker AllocMarker{};
 
   unsigned ReservedSpace;
 
   // Operand[0]    = Value to switch on
   // Operand[1]    = Default basic block destination
   // Operand[2n  ] = Value to match
   // Operand[2n+1] = BasicBlock to go to on match
   SwitchInst(const SwitchInst &SI);
 
   /// 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 can also
   /// auto-insert before another instruction.
   SwitchInst(Value *Value, BasicBlock *Default, unsigned NumCases,
              InsertPosition InsertBefore);
 
   // allocate space for exactly zero operands
   void *operator new(size_t S) { return User::operator new(S, AllocMarker); }
 
   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.
   ///
   /// We define this as a template and instantiate it to form both a const and
   /// non-const handle.
   template <typename SwitchInstT, typename ConstantIntT, typename BasicBlockT>
   class CaseHandleImpl {
     // Directly befriend both const and non-const iterators.
     friend class SwitchInst::CaseIteratorImpl<
         CaseHandleImpl<SwitchInstT, ConstantIntT, BasicBlockT>>;
 
   protected:
     // Expose the switch type we're parameterized with to the iterator.
     using SwitchInstType = SwitchInstT;
 
     SwitchInstT *SI;
     ptrdiff_t Index;
 
     CaseHandleImpl() = default;
     CaseHandleImpl(SwitchInstT *SI, ptrdiff_t Index) : SI(SI), Index(Index) {}
 
   public:
     /// Resolves case value for current case.
     ConstantIntT *getCaseValue() const {
       assert((unsigned)Index < SI->getNumCases() &&
              "Index out the number of cases.");
       return reinterpret_cast<ConstantIntT *>(SI->getOperand(2 + Index * 2));
     }
 
     /// Resolves successor for current case.
     BasicBlockT *getCaseSuccessor() const {
       assert(((unsigned)Index < SI->getNumCases() ||
               (unsigned)Index == DefaultPseudoIndex) &&
              "Index out the number of cases.");
       return SI->getSuccessor(getSuccessorIndex());
     }
 
     /// Returns number of current case.
     unsigned getCaseIndex() const { return Index; }
 
     /// Returns successor index for current case successor.
     unsigned getSuccessorIndex() const {
       assert(((unsigned)Index == DefaultPseudoIndex ||
               (unsigned)Index < SI->getNumCases()) &&
              "Index out the number of cases.");
       return (unsigned)Index != DefaultPseudoIndex ? Index + 1 : 0;
     }
 
     bool operator==(const CaseHandleImpl &RHS) const {
       assert(SI == RHS.SI && "Incompatible operators.");
       return Index == RHS.Index;
     }
   };
 
   using ConstCaseHandle =
       CaseHandleImpl<const SwitchInst, const ConstantInt, const BasicBlock>;
 
   class CaseHandle
       : public CaseHandleImpl<SwitchInst, ConstantInt, BasicBlock> {
     friend class SwitchInst::CaseIteratorImpl<CaseHandle>;
 
   public:
     CaseHandle(SwitchInst *SI, ptrdiff_t Index) : CaseHandleImpl(SI, Index) {}
 
     /// Sets the new value for current case.
     void setValue(ConstantInt *V) const {
       assert((unsigned)Index < SI->getNumCases() &&
              "Index out the number of cases.");
       SI->setOperand(2 + Index*2, reinterpret_cast<Value*>(V));
     }
 
     /// Sets the new successor for current case.
     void setSuccessor(BasicBlock *S) const {
       SI->setSuccessor(getSuccessorIndex(), S);
     }
   };
 
   template <typename CaseHandleT>
   class CaseIteratorImpl
       : public iterator_facade_base<CaseIteratorImpl<CaseHandleT>,
                                     std::random_access_iterator_tag,
                                     const CaseHandleT> {
     using SwitchInstT = typename CaseHandleT::SwitchInstType;
 
     CaseHandleT Case;
 
   public:
     /// Default constructed iterator is in an invalid state until assigned to
     /// a case for a particular switch.
     CaseIteratorImpl() = default;
 
     /// Initializes case iterator for given SwitchInst and for given
     /// case number.
     CaseIteratorImpl(SwitchInstT *SI, unsigned CaseNum) : Case(SI, CaseNum) {}
 
     /// Initializes case iterator for given SwitchInst and for given
     /// successor index.
     static CaseIteratorImpl fromSuccessorIndex(SwitchInstT *SI,
                                                unsigned SuccessorIndex) {
       assert(SuccessorIndex < SI->getNumSuccessors() &&
              "Successor index # out of range!");
       return SuccessorIndex != 0 ? CaseIteratorImpl(SI, SuccessorIndex - 1)
                                  : CaseIteratorImpl(SI, DefaultPseudoIndex);
     }
 
     /// Support converting to the const variant. This will be a no-op for const
     /// variant.
     operator CaseIteratorImpl<ConstCaseHandle>() const {
       return CaseIteratorImpl<ConstCaseHandle>(Case.SI, Case.Index);
     }
 
     CaseIteratorImpl &operator+=(ptrdiff_t N) {
       // Check index correctness after addition.
       // Note: Index == getNumCases() means end().
       assert(Case.Index + N >= 0 &&
              (unsigned)(Case.Index + N) <= Case.SI->getNumCases() &&
              "Case.Index out the number of cases.");
       Case.Index += N;
       return *this;
     }
     CaseIteratorImpl &operator-=(ptrdiff_t N) {
       // Check index correctness after subtraction.
       // Note: Case.Index == getNumCases() means end().
       assert(Case.Index - N >= 0 &&
              (unsigned)(Case.Index - N) <= Case.SI->getNumCases() &&
              "Case.Index out the number of cases.");
       Case.Index -= N;
       return *this;
     }
     ptrdiff_t operator-(const CaseIteratorImpl &RHS) const {
       assert(Case.SI == RHS.Case.SI && "Incompatible operators.");
       return Case.Index - RHS.Case.Index;
     }
     bool operator==(const CaseIteratorImpl &RHS) const {
       return Case == RHS.Case;
     }
     bool operator<(const CaseIteratorImpl &RHS) const {
       assert(Case.SI == RHS.Case.SI && "Incompatible operators.");
       return Case.Index < RHS.Case.Index;
     }
     const CaseHandleT &operator*() const { return Case; }
   };
 
   using CaseIt = CaseIteratorImpl<CaseHandle>;
   using ConstCaseIt = CaseIteratorImpl<ConstCaseHandle>;
 
   static SwitchInst *Create(Value *Value, BasicBlock *Default,
                             unsigned NumCases,
                             InsertPosition InsertBefore = nullptr) {
     return new SwitchInst(Value, Default, NumCases, InsertBefore);
   }
 
   /// Provide fast operand accessors
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   // Accessor Methods for Switch stmt
   Value *getCondition() const { return getOperand(0); }
   void setCondition(Value *V) { setOperand(0, V); }
 
   BasicBlock *getDefaultDest() const {
     return cast<BasicBlock>(getOperand(1));
   }
 
   /// Returns true if the default branch must result in immediate undefined
   /// behavior, false otherwise.
   bool defaultDestUndefined() const {
     return isa<UnreachableInst>(getDefaultDest()->getFirstNonPHIOrDbg());
   }
 
   void setDefaultDest(BasicBlock *DefaultCase) {
     setOperand(1, reinterpret_cast<Value*>(DefaultCase));
   }
 
   /// Return the number of 'cases' in this switch instruction, excluding the
   /// default case.
   unsigned getNumCases() const {
     return getNumOperands()/2 - 1;
   }
 
   /// Returns a read/write iterator that points to the first case in the
   /// SwitchInst.
   CaseIt case_begin() {
     return CaseIt(this, 0);
   }
 
   /// Returns a read-only iterator that points to the first case in the
   /// SwitchInst.
   ConstCaseIt case_begin() const {
     return ConstCaseIt(this, 0);
   }
 
   /// Returns a read/write iterator that points one past the last in the
   /// SwitchInst.
   CaseIt case_end() {
     return CaseIt(this, getNumCases());
   }
 
   /// Returns a read-only iterator that points one past the last in the
   /// SwitchInst.
   ConstCaseIt case_end() const {
     return ConstCaseIt(this, getNumCases());
   }
 
   /// Iteration adapter for range-for loops.
   iterator_range<CaseIt> cases() {
     return make_range(case_begin(), case_end());
   }
 
   /// Constant iteration adapter for range-for loops.
   iterator_range<ConstCaseIt> cases() const {
     return make_range(case_begin(), case_end());
   }
 
   /// Returns an iterator that points to the default case.
   /// Note: this iterator allows to resolve successor only. Attempt
   /// to resolve case value causes an assertion.
   /// Also note, that increment and decrement also causes an assertion and
   /// makes iterator invalid.
   CaseIt case_default() {
     return CaseIt(this, DefaultPseudoIndex);
   }
   ConstCaseIt case_default() const {
     return ConstCaseIt(this, DefaultPseudoIndex);
   }
 
   /// Search all of the case values for the specified constant. If it is
   /// explicitly handled, return the case iterator of it, otherwise return
   /// default case iterator to indicate that it is handled by the default
   /// handler.
   CaseIt findCaseValue(const ConstantInt *C) {
     return CaseIt(
         this,
         const_cast<const SwitchInst *>(this)->findCaseValue(C)->getCaseIndex());
   }
   ConstCaseIt findCaseValue(const ConstantInt *C) const {
     ConstCaseIt I = llvm::find_if(cases(), [C](const ConstCaseHandle &Case) {
       return Case.getCaseValue() == C;
     });
     if (I != case_end())
       return I;
 
     return case_default();
   }
 
   /// Finds the unique case value for a given successor. Returns null if the
   /// successor is not found, not unique, or is the default case.
   ConstantInt *findCaseDest(BasicBlock *BB) {
     if (BB == getDefaultDest())
       return nullptr;
 
     ConstantInt *CI = nullptr;
     for (auto Case : cases()) {
       if (Case.getCaseSuccessor() != BB)
         continue;
 
       if (CI)
         return nullptr; // Multiple cases lead to BB.
 
       CI = Case.getCaseValue();
     }
 
     return CI;
   }
 
   /// Add an entry to the switch instruction.
   /// Note:
   /// This action invalidates case_end(). Old case_end() iterator will
   /// point to the added case.
   void addCase(ConstantInt *OnVal, BasicBlock *Dest);
 
   /// This method removes the specified case and its successor from the switch
   /// instruction. Note that this operation may reorder the remaining cases at
   /// index idx and above.
   /// Note:
   /// This action invalidates iterators for all cases following the one removed,
   /// including the case_end() iterator. It returns an iterator for the next
   /// case.
   CaseIt removeCase(CaseIt I);
 
   unsigned getNumSuccessors() const { return getNumOperands()/2; }
   BasicBlock *getSuccessor(unsigned idx) const {
     assert(idx < getNumSuccessors() &&"Successor idx out of range for switch!");
     return cast<BasicBlock>(getOperand(idx*2+1));
   }
   void setSuccessor(unsigned idx, BasicBlock *NewSucc) {
     assert(idx < getNumSuccessors() && "Successor # out of range for switch!");
     setOperand(idx * 2 + 1, NewSucc);
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::Switch;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 /// A wrapper class to simplify modification of SwitchInst cases along with
 /// their prof branch_weights metadata.
 class SwitchInstProfUpdateWrapper {
   SwitchInst &SI;
   std::optional<SmallVector<uint32_t, 8>> Weights;
   bool Changed = false;
 
 protected:
   MDNode *buildProfBranchWeightsMD();
 
   void init();
 
 public:
   using CaseWeightOpt = std::optional<uint32_t>;
   SwitchInst *operator->() { return &SI; }
   SwitchInst &operator*() { return SI; }
   operator SwitchInst *() { return &SI; }
 
   SwitchInstProfUpdateWrapper(SwitchInst &SI) : SI(SI) { init(); }
 
   ~SwitchInstProfUpdateWrapper() {
     if (Changed)
       SI.setMetadata(LLVMContext::MD_prof, buildProfBranchWeightsMD());
   }
 
   /// Delegate the call to the underlying SwitchInst::removeCase() and remove
   /// correspondent branch weight.
   SwitchInst::CaseIt removeCase(SwitchInst::CaseIt I);
 
   /// Delegate the call to the underlying SwitchInst::addCase() and set the
   /// specified branch weight for the added case.
   void addCase(ConstantInt *OnVal, BasicBlock *Dest, CaseWeightOpt W);
 
   /// Delegate the call to the underlying SwitchInst::eraseFromParent() and mark
   /// this object to not touch the underlying SwitchInst in destructor.
   Instruction::InstListType::iterator eraseFromParent();
 
   void setSuccessorWeight(unsigned idx, CaseWeightOpt W);
   CaseWeightOpt getSuccessorWeight(unsigned idx);
 
   static CaseWeightOpt getSuccessorWeight(const SwitchInst &SI, unsigned idx);
 };
 
 template <> struct OperandTraits<SwitchInst> : public HungoffOperandTraits {};
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(SwitchInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                             IndirectBrInst Class
 //===----------------------------------------------------------------------===//
 
 //===---------------------------------------------------------------------------
 /// Indirect Branch Instruction.
 ///
 class IndirectBrInst : public Instruction {
   constexpr static HungOffOperandsAllocMarker AllocMarker{};
 
   unsigned ReservedSpace;
 
   // Operand[0]   = Address to jump to
   // Operand[n+1] = n-th destination
   IndirectBrInst(const IndirectBrInst &IBI);
 
   /// 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 can also
   /// autoinsert before another instruction.
   IndirectBrInst(Value *Address, unsigned NumDests,
                  InsertPosition InsertBefore);
 
   // allocate space for exactly zero operands
   void *operator new(size_t S) { return User::operator new(S, AllocMarker); }
 
   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 *> {
     explicit succ_op_iterator(value_op_iterator I) : iterator_adaptor_base(I) {}
 
     BasicBlock *operator*() const { return cast<BasicBlock>(*I); }
     BasicBlock *operator->() const { return operator*(); }
   };
 
   /// The const version of `succ_op_iterator`.
   struct const_succ_op_iterator
       : iterator_adaptor_base<const_succ_op_iterator, const_value_op_iterator,
                               std::random_access_iterator_tag,
                               const BasicBlock *, ptrdiff_t, const BasicBlock *,
                               const BasicBlock *> {
     explicit const_succ_op_iterator(const_value_op_iterator I)
         : iterator_adaptor_base(I) {}
 
     const BasicBlock *operator*() const { return cast<BasicBlock>(*I); }
     const BasicBlock *operator->() const { return operator*(); }
   };
 
   static IndirectBrInst *Create(Value *Address, unsigned NumDests,
                                 InsertPosition InsertBefore = nullptr) {
     return new IndirectBrInst(Address, NumDests, InsertBefore);
   }
 
   /// Provide fast operand accessors.
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   // Accessor Methods for IndirectBrInst instruction.
   Value *getAddress() { return getOperand(0); }
   const Value *getAddress() const { return getOperand(0); }
   void setAddress(Value *V) { setOperand(0, V); }
 
   /// return the number of possible destinations in this
   /// indirectbr instruction.
   unsigned getNumDestinations() const { return getNumOperands()-1; }
 
   /// Return the specified destination.
   BasicBlock *getDestination(unsigned i) { return getSuccessor(i); }
   const BasicBlock *getDestination(unsigned i) const { return getSuccessor(i); }
 
   /// Add a destination.
   ///
   void addDestination(BasicBlock *Dest);
 
   /// This method removes the specified successor from the
   /// indirectbr instruction.
   void removeDestination(unsigned i);
 
   unsigned getNumSuccessors() const { return getNumOperands()-1; }
   BasicBlock *getSuccessor(unsigned i) const {
     return cast<BasicBlock>(getOperand(i+1));
   }
   void setSuccessor(unsigned i, BasicBlock *NewSucc) {
     setOperand(i + 1, NewSucc);
   }
 
   iterator_range<succ_op_iterator> successors() {
     return make_range(succ_op_iterator(std::next(value_op_begin())),
                       succ_op_iterator(value_op_end()));
   }
 
   iterator_range<const_succ_op_iterator> successors() const {
     return make_range(const_succ_op_iterator(std::next(value_op_begin())),
                       const_succ_op_iterator(value_op_end()));
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::IndirectBr;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 template <>
 struct OperandTraits<IndirectBrInst> : public HungoffOperandTraits {};
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(IndirectBrInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                               InvokeInst Class
 //===----------------------------------------------------------------------===//
 
 /// Invoke instruction.  The SubclassData field is used to hold the
 /// calling convention of the call.
 ///
 class InvokeInst : public CallBase {
   /// The number of operands for this call beyond the called function,
   /// arguments, and operand bundles.
   static constexpr int NumExtraOperands = 2;
 
   /// The index from the end of the operand array to the normal destination.
   static constexpr int NormalDestOpEndIdx = -3;
 
   /// The index from the end of the operand array to the unwind destination.
   static constexpr int UnwindDestOpEndIdx = -2;
 
   InvokeInst(const InvokeInst &BI, AllocInfo AllocInfo);
 
   /// Construct an InvokeInst given a range of arguments.
   ///
   /// Construct an InvokeInst from a range of arguments
   inline InvokeInst(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
                     BasicBlock *IfException, ArrayRef<Value *> Args,
                     ArrayRef<OperandBundleDef> Bundles, AllocInfo AllocInfo,
                     const Twine &NameStr, InsertPosition InsertBefore);
 
   void init(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
             BasicBlock *IfException, ArrayRef<Value *> Args,
             ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr);
 
   /// Compute the number of operands to allocate.
   static unsigned ComputeNumOperands(unsigned NumArgs,
                                      size_t NumBundleInputs = 0) {
     // We need one operand for the called function, plus our extra operands and
     // the input operand counts provided.
     return 1 + NumExtraOperands + NumArgs + unsigned(NumBundleInputs);
   }
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   InvokeInst *cloneImpl() const;
 
 public:
   static InvokeInst *Create(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
                             BasicBlock *IfException, ArrayRef<Value *> Args,
                             const Twine &NameStr,
                             InsertPosition InsertBefore = nullptr) {
     IntrusiveOperandsAllocMarker AllocMarker{
         ComputeNumOperands(unsigned(Args.size()))};
     return new (AllocMarker) InvokeInst(Ty, Func, IfNormal, IfException, Args,
                                         {}, AllocMarker, NameStr, InsertBefore);
   }
 
   static InvokeInst *Create(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
                             BasicBlock *IfException, ArrayRef<Value *> Args,
                             ArrayRef<OperandBundleDef> Bundles = {},
                             const Twine &NameStr = "",
                             InsertPosition InsertBefore = nullptr) {
     IntrusiveOperandsAndDescriptorAllocMarker AllocMarker{
         ComputeNumOperands(Args.size(), CountBundleInputs(Bundles)),
         unsigned(Bundles.size() * sizeof(BundleOpInfo))};
 
     return new (AllocMarker)
         InvokeInst(Ty, Func, IfNormal, IfException, Args, Bundles, AllocMarker,
                    NameStr, InsertBefore);
   }
 
   static InvokeInst *Create(FunctionCallee Func, BasicBlock *IfNormal,
                             BasicBlock *IfException, ArrayRef<Value *> Args,
                             const Twine &NameStr,
                             InsertPosition InsertBefore = nullptr) {
     return Create(Func.getFunctionType(), Func.getCallee(), IfNormal,
                   IfException, Args, {}, NameStr, InsertBefore);
   }
 
   static InvokeInst *Create(FunctionCallee Func, BasicBlock *IfNormal,
                             BasicBlock *IfException, ArrayRef<Value *> Args,
                             ArrayRef<OperandBundleDef> Bundles = {},
                             const Twine &NameStr = "",
                             InsertPosition InsertBefore = nullptr) {
     return Create(Func.getFunctionType(), Func.getCallee(), IfNormal,
                   IfException, Args, Bundles, NameStr, InsertBefore);
   }
 
   /// Create a clone of \p II with a different set of operand bundles and
   /// insert it before \p InsertBefore.
   ///
   /// The returned invoke instruction is identical to \p II in every way except
   /// that the operand bundles for the new instruction are set to the operand
   /// bundles in \p Bundles.
   static InvokeInst *Create(InvokeInst *II, ArrayRef<OperandBundleDef> Bundles,
                             InsertPosition InsertPt = nullptr);
 
   // get*Dest - Return the destination basic blocks...
   BasicBlock *getNormalDest() const {
     return cast<BasicBlock>(Op<NormalDestOpEndIdx>());
   }
   BasicBlock *getUnwindDest() const {
     return cast<BasicBlock>(Op<UnwindDestOpEndIdx>());
   }
   void setNormalDest(BasicBlock *B) {
     Op<NormalDestOpEndIdx>() = reinterpret_cast<Value *>(B);
   }
   void setUnwindDest(BasicBlock *B) {
     Op<UnwindDestOpEndIdx>() = reinterpret_cast<Value *>(B);
   }
 
   /// Get the landingpad instruction from the landing pad
   /// block (the unwind destination).
   LandingPadInst *getLandingPadInst() const;
 
   BasicBlock *getSuccessor(unsigned i) const {
     assert(i < 2 && "Successor # out of range for invoke!");
     return i == 0 ? getNormalDest() : getUnwindDest();
   }
 
   void setSuccessor(unsigned i, BasicBlock *NewSucc) {
     assert(i < 2 && "Successor # out of range for invoke!");
     if (i == 0)
       setNormalDest(NewSucc);
     else
       setUnwindDest(NewSucc);
   }
 
   unsigned getNumSuccessors() const { return 2; }
 
   /// Updates profile metadata by scaling it by \p S / \p T.
   void updateProfWeight(uint64_t S, uint64_t T);
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return (I->getOpcode() == Instruction::Invoke);
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   // Shadow Instruction::setInstructionSubclassData with a private forwarding
   // method so that subclasses cannot accidentally use it.
   template <typename Bitfield>
   void setSubclassData(typename Bitfield::Type Value) {
     Instruction::setSubclassData<Bitfield>(Value);
   }
 };
 
 InvokeInst::InvokeInst(FunctionType *Ty, Value *Func, BasicBlock *IfNormal,
                        BasicBlock *IfException, ArrayRef<Value *> Args,
                        ArrayRef<OperandBundleDef> Bundles, AllocInfo AllocInfo,
                        const Twine &NameStr, InsertPosition InsertBefore)
     : CallBase(Ty->getReturnType(), Instruction::Invoke, AllocInfo,
                InsertBefore) {
   init(Ty, Func, IfNormal, IfException, Args, Bundles, NameStr);
 }
 
 //===----------------------------------------------------------------------===//
 //                              CallBrInst Class
 //===----------------------------------------------------------------------===//
 
 /// CallBr instruction, tracking function calls that may not return control but
 /// instead transfer it to a third location. The SubclassData field is used to
 /// hold the calling convention of the call.
 ///
 class CallBrInst : public CallBase {
 
   unsigned NumIndirectDests;
 
   CallBrInst(const CallBrInst &BI, AllocInfo AllocInfo);
 
   /// Construct a CallBrInst given a range of arguments.
   ///
   /// Construct a CallBrInst from a range of arguments
   inline CallBrInst(FunctionType *Ty, Value *Func, BasicBlock *DefaultDest,
                     ArrayRef<BasicBlock *> IndirectDests,
                     ArrayRef<Value *> Args, ArrayRef<OperandBundleDef> Bundles,
                     AllocInfo AllocInfo, const Twine &NameStr,
                     InsertPosition InsertBefore);
 
   void init(FunctionType *FTy, Value *Func, BasicBlock *DefaultDest,
             ArrayRef<BasicBlock *> IndirectDests, ArrayRef<Value *> Args,
             ArrayRef<OperandBundleDef> Bundles, const Twine &NameStr);
 
   /// Compute the number of operands to allocate.
   static unsigned ComputeNumOperands(int NumArgs, int NumIndirectDests,
                                      int NumBundleInputs = 0) {
     // We need one operand for the called function, plus our extra operands and
     // the input operand counts provided.
     return unsigned(2 + NumIndirectDests + NumArgs + NumBundleInputs);
   }
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   CallBrInst *cloneImpl() const;
 
 public:
   static CallBrInst *Create(FunctionType *Ty, Value *Func,
                             BasicBlock *DefaultDest,
                             ArrayRef<BasicBlock *> IndirectDests,
                             ArrayRef<Value *> Args, const Twine &NameStr,
                             InsertPosition InsertBefore = nullptr) {
     IntrusiveOperandsAllocMarker AllocMarker{
         ComputeNumOperands(Args.size(), IndirectDests.size())};
     return new (AllocMarker)
         CallBrInst(Ty, Func, DefaultDest, IndirectDests, Args, {}, AllocMarker,
                    NameStr, InsertBefore);
   }
 
   static CallBrInst *
   Create(FunctionType *Ty, Value *Func, BasicBlock *DefaultDest,
          ArrayRef<BasicBlock *> IndirectDests, ArrayRef<Value *> Args,
          ArrayRef<OperandBundleDef> Bundles = {}, const Twine &NameStr = "",
          InsertPosition InsertBefore = nullptr) {
     IntrusiveOperandsAndDescriptorAllocMarker AllocMarker{
         ComputeNumOperands(Args.size(), IndirectDests.size(),
                            CountBundleInputs(Bundles)),
         unsigned(Bundles.size() * sizeof(BundleOpInfo))};
 
     return new (AllocMarker)
         CallBrInst(Ty, Func, DefaultDest, IndirectDests, Args, Bundles,
                    AllocMarker, NameStr, InsertBefore);
   }
 
   static CallBrInst *Create(FunctionCallee Func, BasicBlock *DefaultDest,
                             ArrayRef<BasicBlock *> IndirectDests,
                             ArrayRef<Value *> Args, const Twine &NameStr,
                             InsertPosition InsertBefore = nullptr) {
     return Create(Func.getFunctionType(), Func.getCallee(), DefaultDest,
                   IndirectDests, Args, NameStr, InsertBefore);
   }
 
   static CallBrInst *Create(FunctionCallee Func, BasicBlock *DefaultDest,
                             ArrayRef<BasicBlock *> IndirectDests,
                             ArrayRef<Value *> Args,
                             ArrayRef<OperandBundleDef> Bundles = {},
                             const Twine &NameStr = "",
                             InsertPosition InsertBefore = nullptr) {
     return Create(Func.getFunctionType(), Func.getCallee(), DefaultDest,
                   IndirectDests, Args, Bundles, NameStr, InsertBefore);
   }
 
   /// Create a clone of \p CBI with a different set of operand bundles and
   /// insert it before \p InsertBefore.
   ///
   /// The returned callbr instruction is identical to \p CBI in every way
   /// except that the operand bundles for the new instruction are set to the
   /// operand bundles in \p Bundles.
   static CallBrInst *Create(CallBrInst *CBI, ArrayRef<OperandBundleDef> Bundles,
                             InsertPosition InsertBefore = nullptr);
 
   /// Return the number of callbr indirect dest labels.
   ///
   unsigned getNumIndirectDests() const { return NumIndirectDests; }
 
   /// getIndirectDestLabel - Return the i-th indirect dest label.
   ///
   Value *getIndirectDestLabel(unsigned i) const {
     assert(i < getNumIndirectDests() && "Out of bounds!");
     return getOperand(i + arg_size() + getNumTotalBundleOperands() + 1);
   }
 
   Value *getIndirectDestLabelUse(unsigned i) const {
     assert(i < getNumIndirectDests() && "Out of bounds!");
     return getOperandUse(i + arg_size() + getNumTotalBundleOperands() + 1);
   }
 
   // Return the destination basic blocks...
   BasicBlock *getDefaultDest() const {
     return cast<BasicBlock>(*(&Op<-1>() - getNumIndirectDests() - 1));
   }
   BasicBlock *getIndirectDest(unsigned i) const {
     return cast_or_null<BasicBlock>(*(&Op<-1>() - getNumIndirectDests() + i));
   }
   SmallVector<BasicBlock *, 16> getIndirectDests() const {
     SmallVector<BasicBlock *, 16> IndirectDests;
     for (unsigned i = 0, e = getNumIndirectDests(); i < e; ++i)
       IndirectDests.push_back(getIndirectDest(i));
     return IndirectDests;
   }
   void setDefaultDest(BasicBlock *B) {
     *(&Op<-1>() - getNumIndirectDests() - 1) = reinterpret_cast<Value *>(B);
   }
   void setIndirectDest(unsigned i, BasicBlock *B) {
     *(&Op<-1>() - getNumIndirectDests() + i) = reinterpret_cast<Value *>(B);
   }
 
   BasicBlock *getSuccessor(unsigned i) const {
     assert(i < getNumSuccessors() + 1 &&
            "Successor # out of range for callbr!");
     return i == 0 ? getDefaultDest() : getIndirectDest(i - 1);
   }
 
   void setSuccessor(unsigned i, BasicBlock *NewSucc) {
     assert(i < getNumIndirectDests() + 1 &&
            "Successor # out of range for callbr!");
     return i == 0 ? setDefaultDest(NewSucc) : setIndirectDest(i - 1, NewSucc);
   }
 
   unsigned getNumSuccessors() const { return getNumIndirectDests() + 1; }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return (I->getOpcode() == Instruction::CallBr);
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   // Shadow Instruction::setInstructionSubclassData with a private forwarding
   // method so that subclasses cannot accidentally use it.
   template <typename Bitfield>
   void setSubclassData(typename Bitfield::Type Value) {
     Instruction::setSubclassData<Bitfield>(Value);
   }
 };
 
 CallBrInst::CallBrInst(FunctionType *Ty, Value *Func, BasicBlock *DefaultDest,
                        ArrayRef<BasicBlock *> IndirectDests,
                        ArrayRef<Value *> Args,
                        ArrayRef<OperandBundleDef> Bundles, AllocInfo AllocInfo,
                        const Twine &NameStr, InsertPosition InsertBefore)
     : CallBase(Ty->getReturnType(), Instruction::CallBr, AllocInfo,
                InsertBefore) {
   init(Ty, Func, DefaultDest, IndirectDests, Args, Bundles, NameStr);
 }
 
 //===----------------------------------------------------------------------===//
 //                              ResumeInst Class
 //===----------------------------------------------------------------------===//
 
 //===---------------------------------------------------------------------------
 /// Resume the propagation of an exception.
 ///
 class ResumeInst : public Instruction {
   constexpr static IntrusiveOperandsAllocMarker AllocMarker{1};
 
   ResumeInst(const ResumeInst &RI);
 
   explicit ResumeInst(Value *Exn, InsertPosition InsertBefore = nullptr);
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   ResumeInst *cloneImpl() const;
 
 public:
   static ResumeInst *Create(Value *Exn, InsertPosition InsertBefore = nullptr) {
     return new (AllocMarker) ResumeInst(Exn, InsertBefore);
   }
 
   /// Provide fast operand accessors
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   /// Convenience accessor.
   Value *getValue() const { return Op<0>(); }
 
   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::Resume;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   BasicBlock *getSuccessor(unsigned idx) const {
     llvm_unreachable("ResumeInst has no successors!");
   }
 
   void setSuccessor(unsigned idx, BasicBlock *NewSucc) {
     llvm_unreachable("ResumeInst has no successors!");
   }
 };
 
 template <>
 struct OperandTraits<ResumeInst> :
     public FixedNumOperandTraits<ResumeInst, 1> {
 };
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(ResumeInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                         CatchSwitchInst Class
 //===----------------------------------------------------------------------===//
 class CatchSwitchInst : public Instruction {
   using UnwindDestField = BoolBitfieldElementT<0>;
 
   constexpr static HungOffOperandsAllocMarker AllocMarker{};
 
   /// The number of operands actually allocated.  NumOperands is
   /// the number actually in use.
   unsigned ReservedSpace;
 
   // Operand[0] = Outer scope
   // Operand[1] = Unwind block destination
   // Operand[n] = BasicBlock to go to on match
   CatchSwitchInst(const CatchSwitchInst &CSI);
 
   /// Create a new switch instruction, specifying a
   /// default destination.  The number of additional handlers can be specified
   /// here to make memory allocation more efficient.
   /// This constructor can also autoinsert before another instruction.
   CatchSwitchInst(Value *ParentPad, BasicBlock *UnwindDest,
                   unsigned NumHandlers, const Twine &NameStr,
                   InsertPosition InsertBefore);
 
   // allocate space for exactly zero operands
   void *operator new(size_t S) { return User::operator new(S, AllocMarker); }
 
   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 = "",
                                  InsertPosition InsertBefore = nullptr) {
     return new CatchSwitchInst(ParentPad, UnwindDest, NumHandlers, NameStr,
                                InsertBefore);
   }
 
   /// Provide fast operand accessors
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   // Accessor Methods for CatchSwitch stmt
   Value *getParentPad() const { return getOperand(0); }
   void setParentPad(Value *ParentPad) { setOperand(0, ParentPad); }
 
   // Accessor Methods for CatchSwitch stmt
   bool hasUnwindDest() const { return getSubclassData<UnwindDestField>(); }
   bool unwindsToCaller() const { return !hasUnwindDest(); }
   BasicBlock *getUnwindDest() const {
     if (hasUnwindDest())
       return cast<BasicBlock>(getOperand(1));
     return nullptr;
   }
   void setUnwindDest(BasicBlock *UnwindDest) {
     assert(UnwindDest);
     assert(hasUnwindDest());
     setOperand(1, UnwindDest);
   }
 
   /// return the number of 'handlers' in this catchswitch
   /// instruction, except the default handler
   unsigned getNumHandlers() const {
     if (hasUnwindDest())
       return getNumOperands() - 2;
     return getNumOperands() - 1;
   }
 
 private:
   static BasicBlock *handler_helper(Value *V) { return cast<BasicBlock>(V); }
   static const BasicBlock *handler_helper(const Value *V) {
     return cast<BasicBlock>(V);
   }
 
 public:
   using DerefFnTy = BasicBlock *(*)(Value *);
   using handler_iterator = mapped_iterator<op_iterator, DerefFnTy>;
   using handler_range = iterator_range<handler_iterator>;
   using ConstDerefFnTy = const BasicBlock *(*)(const Value *);
   using const_handler_iterator =
       mapped_iterator<const_op_iterator, ConstDerefFnTy>;
   using const_handler_range = iterator_range<const_handler_iterator>;
 
   /// Returns an iterator that points to the first handler in CatchSwitchInst.
   handler_iterator handler_begin() {
     op_iterator It = op_begin() + 1;
     if (hasUnwindDest())
       ++It;
     return handler_iterator(It, DerefFnTy(handler_helper));
   }
 
   /// Returns an iterator that points to the first handler in the
   /// CatchSwitchInst.
   const_handler_iterator handler_begin() const {
     const_op_iterator It = op_begin() + 1;
     if (hasUnwindDest())
       ++It;
     return const_handler_iterator(It, ConstDerefFnTy(handler_helper));
   }
 
   /// Returns a read-only iterator that points one past the last
   /// handler in the CatchSwitchInst.
   handler_iterator handler_end() {
     return handler_iterator(op_end(), DerefFnTy(handler_helper));
   }
 
   /// Returns an iterator that points one past the last handler in the
   /// CatchSwitchInst.
   const_handler_iterator handler_end() const {
     return const_handler_iterator(op_end(), ConstDerefFnTy(handler_helper));
   }
 
   /// iteration adapter for range-for loops.
   handler_range handlers() {
     return make_range(handler_begin(), handler_end());
   }
 
   /// iteration adapter for range-for loops.
   const_handler_range handlers() const {
     return make_range(handler_begin(), handler_end());
   }
 
   /// Add an entry to the switch instruction...
   /// Note:
   /// This action invalidates handler_end(). Old handler_end() iterator will
   /// point to the added handler.
   void addHandler(BasicBlock *Dest);
 
   void removeHandler(handler_iterator HI);
 
   unsigned getNumSuccessors() const { return getNumOperands() - 1; }
   BasicBlock *getSuccessor(unsigned Idx) const {
     assert(Idx < getNumSuccessors() &&
            "Successor # out of range for catchswitch!");
     return cast<BasicBlock>(getOperand(Idx + 1));
   }
   void setSuccessor(unsigned Idx, BasicBlock *NewSucc) {
     assert(Idx < getNumSuccessors() &&
            "Successor # out of range for catchswitch!");
     setOperand(Idx + 1, NewSucc);
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::CatchSwitch;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 template <>
 struct OperandTraits<CatchSwitchInst> : public HungoffOperandTraits {};
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(CatchSwitchInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                               CleanupPadInst Class
 //===----------------------------------------------------------------------===//
 class CleanupPadInst : public FuncletPadInst {
 private:
   explicit CleanupPadInst(Value *ParentPad, ArrayRef<Value *> Args,
                           AllocInfo AllocInfo, const Twine &NameStr,
                           InsertPosition InsertBefore)
       : FuncletPadInst(Instruction::CleanupPad, ParentPad, Args, AllocInfo,
                        NameStr, InsertBefore) {}
 
 public:
   static CleanupPadInst *Create(Value *ParentPad, ArrayRef<Value *> Args = {},
                                 const Twine &NameStr = "",
                                 InsertPosition InsertBefore = nullptr) {
     IntrusiveOperandsAllocMarker AllocMarker{unsigned(1 + Args.size())};
     return new (AllocMarker)
         CleanupPadInst(ParentPad, Args, AllocMarker, NameStr, InsertBefore);
   }
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::CleanupPad;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                               CatchPadInst Class
 //===----------------------------------------------------------------------===//
 class CatchPadInst : public FuncletPadInst {
 private:
   explicit CatchPadInst(Value *CatchSwitch, ArrayRef<Value *> Args,
                         AllocInfo AllocInfo, const Twine &NameStr,
                         InsertPosition InsertBefore)
       : FuncletPadInst(Instruction::CatchPad, CatchSwitch, Args, AllocInfo,
                        NameStr, InsertBefore) {}
 
 public:
   static CatchPadInst *Create(Value *CatchSwitch, ArrayRef<Value *> Args,
                               const Twine &NameStr = "",
                               InsertPosition InsertBefore = nullptr) {
     IntrusiveOperandsAllocMarker AllocMarker{unsigned(1 + Args.size())};
     return new (AllocMarker)
         CatchPadInst(CatchSwitch, Args, AllocMarker, NameStr, InsertBefore);
   }
 
   /// Convenience accessors
   CatchSwitchInst *getCatchSwitch() const {
     return cast<CatchSwitchInst>(Op<-1>());
   }
   void setCatchSwitch(Value *CatchSwitch) {
     assert(CatchSwitch);
     Op<-1>() = CatchSwitch;
   }
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Instruction::CatchPad;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                               CatchReturnInst Class
 //===----------------------------------------------------------------------===//
 
 class CatchReturnInst : public Instruction {
   constexpr static IntrusiveOperandsAllocMarker AllocMarker{2};
 
   CatchReturnInst(const CatchReturnInst &RI);
   CatchReturnInst(Value *CatchPad, BasicBlock *BB, InsertPosition InsertBefore);
 
   void init(Value *CatchPad, BasicBlock *BB);
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   CatchReturnInst *cloneImpl() const;
 
 public:
   static CatchReturnInst *Create(Value *CatchPad, BasicBlock *BB,
                                  InsertPosition InsertBefore = nullptr) {
     assert(CatchPad);
     assert(BB);
     return new (AllocMarker) CatchReturnInst(CatchPad, BB, InsertBefore);
   }
 
   /// Provide fast operand accessors
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   /// Convenience accessors.
   CatchPadInst *getCatchPad() const { return cast<CatchPadInst>(Op<0>()); }
   void setCatchPad(CatchPadInst *CatchPad) {
     assert(CatchPad);
     Op<0>() = CatchPad;
   }
 
   BasicBlock *getSuccessor() const { return cast<BasicBlock>(Op<1>()); }
   void setSuccessor(BasicBlock *NewSucc) {
     assert(NewSucc);
     Op<1>() = NewSucc;
   }
   unsigned getNumSuccessors() const { return 1; }
 
   /// Get the parentPad of this catchret's catchpad's catchswitch.
   /// The successor block is implicitly a member of this funclet.
   Value *getCatchSwitchParentPad() const {
     return getCatchPad()->getCatchSwitch()->getParentPad();
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return (I->getOpcode() == Instruction::CatchRet);
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   BasicBlock *getSuccessor(unsigned Idx) const {
     assert(Idx < getNumSuccessors() && "Successor # out of range for catchret!");
     return getSuccessor();
   }
 
   void setSuccessor(unsigned Idx, BasicBlock *B) {
     assert(Idx < getNumSuccessors() && "Successor # out of range for catchret!");
     setSuccessor(B);
   }
 };
 
 template <>
 struct OperandTraits<CatchReturnInst>
     : public FixedNumOperandTraits<CatchReturnInst, 2> {};
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(CatchReturnInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                               CleanupReturnInst Class
 //===----------------------------------------------------------------------===//
 
 class CleanupReturnInst : public Instruction {
   using UnwindDestField = BoolBitfieldElementT<0>;
 
 private:
   CleanupReturnInst(const CleanupReturnInst &RI, AllocInfo AllocInfo);
   CleanupReturnInst(Value *CleanupPad, BasicBlock *UnwindBB,
                     AllocInfo AllocInfo, InsertPosition InsertBefore = nullptr);
 
   void init(Value *CleanupPad, BasicBlock *UnwindBB);
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   CleanupReturnInst *cloneImpl() const;
 
 public:
   static CleanupReturnInst *Create(Value *CleanupPad,
                                    BasicBlock *UnwindBB = nullptr,
                                    InsertPosition InsertBefore = nullptr) {
     assert(CleanupPad);
     unsigned Values = 1;
     if (UnwindBB)
       ++Values;
     IntrusiveOperandsAllocMarker AllocMarker{Values};
     return new (AllocMarker)
         CleanupReturnInst(CleanupPad, UnwindBB, AllocMarker, InsertBefore);
   }
 
   /// Provide fast operand accessors
   DECLARE_TRANSPARENT_OPERAND_ACCESSORS(Value);
 
   bool hasUnwindDest() const { return getSubclassData<UnwindDestField>(); }
   bool unwindsToCaller() const { return !hasUnwindDest(); }
 
   /// Convenience accessor.
   CleanupPadInst *getCleanupPad() const {
     return cast<CleanupPadInst>(Op<0>());
   }
   void setCleanupPad(CleanupPadInst *CleanupPad) {
     assert(CleanupPad);
     Op<0>() = CleanupPad;
   }
 
   unsigned getNumSuccessors() const { return hasUnwindDest() ? 1 : 0; }
 
   BasicBlock *getUnwindDest() const {
     return hasUnwindDest() ? cast<BasicBlock>(Op<1>()) : nullptr;
   }
   void setUnwindDest(BasicBlock *NewDest) {
     assert(NewDest);
     assert(hasUnwindDest());
     Op<1>() = NewDest;
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return (I->getOpcode() == Instruction::CleanupRet);
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   BasicBlock *getSuccessor(unsigned Idx) const {
     assert(Idx == 0);
     return getUnwindDest();
   }
 
   void setSuccessor(unsigned Idx, BasicBlock *B) {
     assert(Idx == 0);
     setUnwindDest(B);
   }
 
   // Shadow Instruction::setInstructionSubclassData with a private forwarding
   // method so that subclasses cannot accidentally use it.
   template <typename Bitfield>
   void setSubclassData(typename Bitfield::Type Value) {
     Instruction::setSubclassData<Bitfield>(Value);
   }
 };
 
 template <>
 struct OperandTraits<CleanupReturnInst>
     : public VariadicOperandTraits<CleanupReturnInst> {};
 
 DEFINE_TRANSPARENT_OPERAND_ACCESSORS(CleanupReturnInst, Value)
 
 //===----------------------------------------------------------------------===//
 //                           UnreachableInst Class
 //===----------------------------------------------------------------------===//
 
 //===---------------------------------------------------------------------------
 /// This function has undefined behavior.  In particular, the
 /// presence of this instruction indicates some higher level knowledge that the
 /// end of the block cannot be reached.
 ///
 class UnreachableInst : public Instruction {
   constexpr static IntrusiveOperandsAllocMarker AllocMarker{0};
 
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   UnreachableInst *cloneImpl() const;
 
 public:
   explicit UnreachableInst(LLVMContext &C,
                            InsertPosition InsertBefore = nullptr);
 
   // allocate space for exactly zero operands
   void *operator new(size_t S) { return User::operator new(S, AllocMarker); }
   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) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
 private:
   BasicBlock *getSuccessor(unsigned idx) const {
     llvm_unreachable("UnreachableInst has no successors!");
   }
 
   void setSuccessor(unsigned idx, BasicBlock *B) {
     llvm_unreachable("UnreachableInst has no successors!");
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                 TruncInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents a truncation of integer types.
 class TruncInst : public CastInst {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical TruncInst
   TruncInst *cloneImpl() const;
 
 public:
   enum { AnyWrap = 0, NoUnsignedWrap = (1 << 0), NoSignedWrap = (1 << 1) };
 
   /// Constructor with insert-before-instruction semantics
   TruncInst(Value *S,                  ///< The value to be truncated
             Type *Ty,                  ///< The (smaller) type to truncate to
             const Twine &NameStr = "", ///< A name for the new instruction
             InsertPosition InsertBefore =
                 nullptr ///< Where to insert the new instruction
   );
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == Trunc;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
   void setHasNoUnsignedWrap(bool B) {
     SubclassOptionalData =
         (SubclassOptionalData & ~NoUnsignedWrap) | (B * NoUnsignedWrap);
   }
   void setHasNoSignedWrap(bool B) {
     SubclassOptionalData =
         (SubclassOptionalData & ~NoSignedWrap) | (B * NoSignedWrap);
   }
 
   /// Test whether this operation is known to never
   /// undergo unsigned overflow, aka the nuw property.
   bool hasNoUnsignedWrap() const {
     return SubclassOptionalData & NoUnsignedWrap;
   }
 
   /// Test whether this operation is known to never
   /// undergo signed overflow, aka the nsw property.
   bool hasNoSignedWrap() const {
     return (SubclassOptionalData & NoSignedWrap) != 0;
   }
 
   /// Returns the no-wrap kind of the operation.
   unsigned getNoWrapKind() const {
     unsigned NoWrapKind = 0;
     if (hasNoUnsignedWrap())
       NoWrapKind |= NoUnsignedWrap;
 
     if (hasNoSignedWrap())
       NoWrapKind |= NoSignedWrap;
 
     return NoWrapKind;
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                 ZExtInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents zero extension of integer types.
 class ZExtInst : public CastInst {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical ZExtInst
   ZExtInst *cloneImpl() const;
 
 public:
   /// Constructor with insert-before-instruction semantics
   ZExtInst(Value *S,                  ///< The value to be zero extended
            Type *Ty,                  ///< The type to zero extend to
            const Twine &NameStr = "", ///< A name for the new instruction
            InsertPosition InsertBefore =
                nullptr ///< Where to insert the new instruction
   );
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == ZExt;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                 SExtInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents a sign extension of integer types.
 class SExtInst : public CastInst {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical SExtInst
   SExtInst *cloneImpl() const;
 
 public:
   /// Constructor with insert-before-instruction semantics
   SExtInst(Value *S,                  ///< The value to be sign extended
            Type *Ty,                  ///< The type to sign extend to
            const Twine &NameStr = "", ///< A name for the new instruction
            InsertPosition InsertBefore =
                nullptr ///< Where to insert the new instruction
   );
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == SExt;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                 FPTruncInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents a truncation of floating point types.
 class FPTruncInst : public CastInst {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical FPTruncInst
   FPTruncInst *cloneImpl() const;
 
 public:                 /// Constructor with insert-before-instruction semantics
   FPTruncInst(Value *S, ///< The value to be truncated
               Type *Ty, ///< The type to truncate to
               const Twine &NameStr = "", ///< A name for the new instruction
               InsertPosition InsertBefore =
                   nullptr ///< Where to insert the new instruction
   );
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == FPTrunc;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                 FPExtInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents an extension of floating point types.
 class FPExtInst : public CastInst {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical FPExtInst
   FPExtInst *cloneImpl() const;
 
 public:
   /// Constructor with insert-before-instruction semantics
   FPExtInst(Value *S,                  ///< The value to be extended
             Type *Ty,                  ///< The type to extend to
             const Twine &NameStr = "", ///< A name for the new instruction
             InsertPosition InsertBefore =
                 nullptr ///< Where to insert the new instruction
   );
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == FPExt;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                 UIToFPInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents a cast unsigned integer to floating point.
 class UIToFPInst : public CastInst {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical UIToFPInst
   UIToFPInst *cloneImpl() const;
 
 public:
   /// Constructor with insert-before-instruction semantics
   UIToFPInst(Value *S,                  ///< The value to be converted
              Type *Ty,                  ///< The type to convert to
              const Twine &NameStr = "", ///< A name for the new instruction
              InsertPosition InsertBefore =
                  nullptr ///< Where to insert the new instruction
   );
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == UIToFP;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                 SIToFPInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents a cast from signed integer to floating point.
 class SIToFPInst : public CastInst {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical SIToFPInst
   SIToFPInst *cloneImpl() const;
 
 public:
   /// Constructor with insert-before-instruction semantics
   SIToFPInst(Value *S,                  ///< The value to be converted
              Type *Ty,                  ///< The type to convert to
              const Twine &NameStr = "", ///< A name for the new instruction
              InsertPosition InsertBefore =
                  nullptr ///< Where to insert the new instruction
   );
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == SIToFP;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                 FPToUIInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents a cast from floating point to unsigned integer
 class FPToUIInst  : public CastInst {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical FPToUIInst
   FPToUIInst *cloneImpl() const;
 
 public:
   /// Constructor with insert-before-instruction semantics
   FPToUIInst(Value *S,                  ///< The value to be converted
              Type *Ty,                  ///< The type to convert to
              const Twine &NameStr = "", ///< A name for the new instruction
              InsertPosition InsertBefore =
                  nullptr ///< Where to insert the new instruction
   );
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == FPToUI;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                 FPToSIInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents a cast from floating point to signed integer.
 class FPToSIInst  : public CastInst {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical FPToSIInst
   FPToSIInst *cloneImpl() const;
 
 public:
   /// Constructor with insert-before-instruction semantics
   FPToSIInst(Value *S,                  ///< The value to be converted
              Type *Ty,                  ///< The type to convert to
              const Twine &NameStr = "", ///< A name for the new instruction
              InsertPosition InsertBefore =
                  nullptr ///< Where to insert the new instruction
   );
 
   /// Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == FPToSI;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                 IntToPtrInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents a cast from an integer to a pointer.
 class IntToPtrInst : public CastInst {
 public:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Constructor with insert-before-instruction semantics
   IntToPtrInst(Value *S,                  ///< The value to be converted
                Type *Ty,                  ///< The type to convert to
                const Twine &NameStr = "", ///< A name for the new instruction
                InsertPosition InsertBefore =
                    nullptr ///< Where to insert the new instruction
   );
 
   /// Clone an identical IntToPtrInst.
   IntToPtrInst *cloneImpl() const;
 
   /// Returns the address space of this instruction's pointer type.
   unsigned getAddressSpace() const {
     return getType()->getPointerAddressSpace();
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == IntToPtr;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                                 PtrToIntInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents a cast from a pointer to an integer.
 class PtrToIntInst : public CastInst {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical PtrToIntInst.
   PtrToIntInst *cloneImpl() const;
 
 public:
   /// Constructor with insert-before-instruction semantics
   PtrToIntInst(Value *S,                  ///< The value to be converted
                Type *Ty,                  ///< The type to convert to
                const Twine &NameStr = "", ///< A name for the new instruction
                InsertPosition InsertBefore =
                    nullptr ///< Where to insert the new instruction
   );
 
   /// Gets the pointer operand.
   Value *getPointerOperand() { return getOperand(0); }
   /// Gets the pointer operand.
   const Value *getPointerOperand() const { return getOperand(0); }
   /// Gets the operand index of the pointer operand.
   static unsigned getPointerOperandIndex() { return 0U; }
 
   /// Returns the address space of the pointer operand.
   unsigned getPointerAddressSpace() const {
     return getPointerOperand()->getType()->getPointerAddressSpace();
   }
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == PtrToInt;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                             BitCastInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents a no-op cast from one type to another.
 class BitCastInst : public CastInst {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical BitCastInst.
   BitCastInst *cloneImpl() const;
 
 public:
   /// Constructor with insert-before-instruction semantics
   BitCastInst(Value *S,                  ///< The value to be casted
               Type *Ty,                  ///< The type to casted to
               const Twine &NameStr = "", ///< A name for the new instruction
               InsertPosition InsertBefore =
                   nullptr ///< Where to insert the new instruction
   );
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == BitCast;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                          AddrSpaceCastInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents a conversion between pointers from one address space
 /// to another.
 class AddrSpaceCastInst : public CastInst {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical AddrSpaceCastInst.
   AddrSpaceCastInst *cloneImpl() const;
 
 public:
   /// Constructor with insert-before-instruction semantics
   AddrSpaceCastInst(
       Value *S,                  ///< The value to be casted
       Type *Ty,                  ///< The type to casted to
       const Twine &NameStr = "", ///< A name for the new instruction
       InsertPosition InsertBefore =
           nullptr ///< Where to insert the new instruction
   );
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static bool classof(const Instruction *I) {
     return I->getOpcode() == AddrSpaceCast;
   }
   static bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 
   /// Gets the pointer operand.
   Value *getPointerOperand() {
     return getOperand(0);
   }
 
   /// Gets the pointer operand.
   const Value *getPointerOperand() const {
     return getOperand(0);
   }
 
   /// Gets the operand index of the pointer operand.
   static unsigned getPointerOperandIndex() {
     return 0U;
   }
 
   /// Returns the address space of the pointer operand.
   unsigned getSrcAddressSpace() const {
     return getPointerOperand()->getType()->getPointerAddressSpace();
   }
 
   /// Returns the address space of the result.
   unsigned getDestAddressSpace() const {
     return getType()->getPointerAddressSpace();
   }
 };
 
 //===----------------------------------------------------------------------===//
 //                          Helper functions
 //===----------------------------------------------------------------------===//
 
 /// A helper function that returns the pointer operand of a load or store
 /// instruction. Returns nullptr if not load or store.
 inline const Value *getLoadStorePointerOperand(const Value *V) {
   if (auto *Load = dyn_cast<LoadInst>(V))
     return Load->getPointerOperand();
   if (auto *Store = dyn_cast<StoreInst>(V))
     return Store->getPointerOperand();
   return nullptr;
 }
 inline Value *getLoadStorePointerOperand(Value *V) {
   return const_cast<Value *>(
       getLoadStorePointerOperand(static_cast<const Value *>(V)));
 }
 
 /// A helper function that returns the pointer operand of a load, store
 /// or GEP instruction. Returns nullptr if not load, store, or GEP.
 inline const Value *getPointerOperand(const Value *V) {
   if (auto *Ptr = getLoadStorePointerOperand(V))
     return Ptr;
   if (auto *Gep = dyn_cast<GetElementPtrInst>(V))
     return Gep->getPointerOperand();
   return nullptr;
 }
 inline Value *getPointerOperand(Value *V) {
   return const_cast<Value *>(getPointerOperand(static_cast<const Value *>(V)));
 }
 
 /// A helper function that returns the alignment of load or store instruction.
 inline Align getLoadStoreAlignment(const Value *I) {
   assert((isa<LoadInst>(I) || isa<StoreInst>(I)) &&
          "Expected Load or Store instruction");
   if (auto *LI = dyn_cast<LoadInst>(I))
     return LI->getAlign();
   return cast<StoreInst>(I)->getAlign();
 }
 
 /// A helper function that set the alignment of load or store instruction.
 inline void setLoadStoreAlignment(Value *I, Align NewAlign) {
   assert((isa<LoadInst>(I) || isa<StoreInst>(I)) &&
          "Expected Load or Store instruction");
   if (auto *LI = dyn_cast<LoadInst>(I))
     LI->setAlignment(NewAlign);
   else
     cast<StoreInst>(I)->setAlignment(NewAlign);
 }
 
 /// A helper function that returns the address space of the pointer operand of
 /// load or store instruction.
 inline unsigned getLoadStoreAddressSpace(const Value *I) {
   assert((isa<LoadInst>(I) || isa<StoreInst>(I)) &&
          "Expected Load or Store instruction");
   if (auto *LI = dyn_cast<LoadInst>(I))
     return LI->getPointerAddressSpace();
   return cast<StoreInst>(I)->getPointerAddressSpace();
 }
 
 /// A helper function that returns the type of a load or store instruction.
 inline Type *getLoadStoreType(const Value *I) {
   assert((isa<LoadInst>(I) || isa<StoreInst>(I)) &&
          "Expected Load or Store instruction");
   if (auto *LI = dyn_cast<LoadInst>(I))
     return LI->getType();
   return cast<StoreInst>(I)->getValueOperand()->getType();
 }
 
 /// A helper function that returns an atomic operation's sync scope; returns
 /// std::nullopt if it is not an atomic operation.
 inline std::optional<SyncScope::ID> getAtomicSyncScopeID(const Instruction *I) {
   if (!I->isAtomic())
     return std::nullopt;
   if (auto *AI = dyn_cast<LoadInst>(I))
     return AI->getSyncScopeID();
   if (auto *AI = dyn_cast<StoreInst>(I))
     return AI->getSyncScopeID();
   if (auto *AI = dyn_cast<FenceInst>(I))
     return AI->getSyncScopeID();
   if (auto *AI = dyn_cast<AtomicCmpXchgInst>(I))
     return AI->getSyncScopeID();
   if (auto *AI = dyn_cast<AtomicRMWInst>(I))
     return AI->getSyncScopeID();
   llvm_unreachable("unhandled atomic operation");
 }
 
 /// A helper function that sets an atomic operation's sync scope.
 inline void setAtomicSyncScopeID(Instruction *I, SyncScope::ID SSID) {
   assert(I->isAtomic());
   if (auto *AI = dyn_cast<LoadInst>(I))
     AI->setSyncScopeID(SSID);
   else if (auto *AI = dyn_cast<StoreInst>(I))
     AI->setSyncScopeID(SSID);
   else if (auto *AI = dyn_cast<FenceInst>(I))
     AI->setSyncScopeID(SSID);
   else if (auto *AI = dyn_cast<AtomicCmpXchgInst>(I))
     AI->setSyncScopeID(SSID);
   else if (auto *AI = dyn_cast<AtomicRMWInst>(I))
     AI->setSyncScopeID(SSID);
   else
     llvm_unreachable("unhandled atomic operation");
 }
 
 //===----------------------------------------------------------------------===//
 //                              FreezeInst Class
 //===----------------------------------------------------------------------===//
 
 /// This class represents a freeze function that returns random concrete
 /// value if an operand is either a poison value or an undef value
 class FreezeInst : public UnaryInstruction {
 protected:
   // Note: Instruction needs to be a friend here to call cloneImpl.
   friend class Instruction;
 
   /// Clone an identical FreezeInst
   FreezeInst *cloneImpl() const;
 
 public:
   explicit FreezeInst(Value *S, const Twine &NameStr = "",
                       InsertPosition InsertBefore = nullptr);
 
   // Methods for support type inquiry through isa, cast, and dyn_cast:
   static inline bool classof(const Instruction *I) {
     return I->getOpcode() == Freeze;
   }
   static inline bool classof(const Value *V) {
     return isa<Instruction>(V) && classof(cast<Instruction>(V));
   }
 };
 
 } // end namespace llvm
 
 #endif // LLVM_IR_INSTRUCTIONS_H