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 //===- llvm/CodeGen/SelectionDAG.h - InstSelection DAG ----------*- 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 declares the SelectionDAG class, and transitively defines the
 // SDNode class and subclasses.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CODEGEN_SELECTIONDAG_H
 #define LLVM_CODEGEN_SELECTIONDAG_H
 
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/DenseSet.h"
 #include "llvm/ADT/FoldingSet.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/StringMap.h"
 #include "llvm/ADT/ilist.h"
 #include "llvm/ADT/iterator.h"
 #include "llvm/ADT/iterator_range.h"
 #include "llvm/CodeGen/DAGCombine.h"
 #include "llvm/CodeGen/ISDOpcodes.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineMemOperand.h"
 #include "llvm/CodeGen/MachinePassManager.h"
 #include "llvm/CodeGen/SelectionDAGNodes.h"
 #include "llvm/CodeGen/ValueTypes.h"
 #include "llvm/CodeGenTypes/MachineValueType.h"
 #include "llvm/IR/ConstantRange.h"
 #include "llvm/IR/DebugLoc.h"
 #include "llvm/IR/Metadata.h"
 #include "llvm/IR/RuntimeLibcalls.h"
 #include "llvm/Support/Allocator.h"
 #include "llvm/Support/ArrayRecycler.h"
 #include "llvm/Support/CodeGen.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/RecyclingAllocator.h"
 #include <cassert>
 #include <cstdint>
 #include <functional>
 #include <map>
 #include <set>
 #include <string>
 #include <tuple>
 #include <utility>
 #include <vector>
 
 namespace llvm {
 
 class DIExpression;
 class DILabel;
 class DIVariable;
 class Function;
 class Pass;
 class Type;
 template <class GraphType> struct GraphTraits;
 template <typename T, unsigned int N> class SmallSetVector;
 template <typename T, typename Enable> struct FoldingSetTrait;
 class BatchAAResults;
 class BlockAddress;
 class BlockFrequencyInfo;
 class Constant;
 class ConstantFP;
 class ConstantInt;
 class DataLayout;
 struct fltSemantics;
 class FunctionLoweringInfo;
 class FunctionVarLocs;
 class GlobalValue;
 struct KnownBits;
 class LLVMContext;
 class MachineBasicBlock;
 class MachineConstantPoolValue;
 class MachineModuleInfo;
 class MCSymbol;
 class OptimizationRemarkEmitter;
 class ProfileSummaryInfo;
 class SDDbgValue;
 class SDDbgOperand;
 class SDDbgLabel;
 class SelectionDAG;
 class SelectionDAGTargetInfo;
 class TargetLibraryInfo;
 class TargetLowering;
 class TargetMachine;
 class TargetSubtargetInfo;
 class Value;
 
 template <typename T> class GenericSSAContext;
 using SSAContext = GenericSSAContext<Function>;
 template <typename T> class GenericUniformityInfo;
 using UniformityInfo = GenericUniformityInfo<SSAContext>;
 
 class SDVTListNode : public FoldingSetNode {
   friend struct FoldingSetTrait<SDVTListNode>;
 
   /// A reference to an Interned FoldingSetNodeID for this node.
   /// The Allocator in SelectionDAG holds the data.
   /// SDVTList contains all types which are frequently accessed in SelectionDAG.
   /// The size of this list is not expected to be big so it won't introduce
   /// a memory penalty.
   FoldingSetNodeIDRef FastID;
   const EVT *VTs;
   unsigned int NumVTs;
   /// The hash value for SDVTList is fixed, so cache it to avoid
   /// hash calculation.
   unsigned HashValue;
 
 public:
   SDVTListNode(const FoldingSetNodeIDRef ID, const EVT *VT, unsigned int Num) :
       FastID(ID), VTs(VT), NumVTs(Num) {
     HashValue = ID.ComputeHash();
   }
 
   SDVTList getSDVTList() {
     SDVTList result = {VTs, NumVTs};
     return result;
   }
 };
 
 /// Specialize FoldingSetTrait for SDVTListNode
 /// to avoid computing temp FoldingSetNodeID and hash value.
 template<> struct FoldingSetTrait<SDVTListNode> : DefaultFoldingSetTrait<SDVTListNode> {
   static void Profile(const SDVTListNode &X, FoldingSetNodeID& ID) {
     ID = X.FastID;
   }
 
   static bool Equals(const SDVTListNode &X, const FoldingSetNodeID &ID,
                      unsigned IDHash, FoldingSetNodeID &TempID) {
     if (X.HashValue != IDHash)
       return false;
     return ID == X.FastID;
   }
 
   static unsigned ComputeHash(const SDVTListNode &X, FoldingSetNodeID &TempID) {
     return X.HashValue;
   }
 };
 
 template <> struct ilist_alloc_traits<SDNode> {
   static void deleteNode(SDNode *) {
     llvm_unreachable("ilist_traits<SDNode> shouldn't see a deleteNode call!");
   }
 };
 
 /// Keeps track of dbg_value information through SDISel.  We do
 /// not build SDNodes for these so as not to perturb the generated code;
 /// instead the info is kept off to the side in this structure. Each SDNode may
 /// have one or more associated dbg_value entries. This information is kept in
 /// DbgValMap.
 /// Byval parameters are handled separately because they don't use alloca's,
 /// which busts the normal mechanism.  There is good reason for handling all
 /// parameters separately:  they may not have code generated for them, they
 /// should always go at the beginning of the function regardless of other code
 /// motion, and debug info for them is potentially useful even if the parameter
 /// is unused.  Right now only byval parameters are handled separately.
 class SDDbgInfo {
   BumpPtrAllocator Alloc;
   SmallVector<SDDbgValue*, 32> DbgValues;
   SmallVector<SDDbgValue*, 32> ByvalParmDbgValues;
   SmallVector<SDDbgLabel*, 4> DbgLabels;
   using DbgValMapType = DenseMap<const SDNode *, SmallVector<SDDbgValue *, 2>>;
   DbgValMapType DbgValMap;
 
 public:
   SDDbgInfo() = default;
   SDDbgInfo(const SDDbgInfo &) = delete;
   SDDbgInfo &operator=(const SDDbgInfo &) = delete;
 
   void add(SDDbgValue *V, bool isParameter);
 
   void add(SDDbgLabel *L) { DbgLabels.push_back(L); }
 
   /// Invalidate all DbgValues attached to the node and remove
   /// it from the Node-to-DbgValues map.
   void erase(const SDNode *Node);
 
   void clear() {
     DbgValMap.clear();
     DbgValues.clear();
     ByvalParmDbgValues.clear();
     DbgLabels.clear();
     Alloc.Reset();
   }
 
   BumpPtrAllocator &getAlloc() { return Alloc; }
 
   bool empty() const {
     return DbgValues.empty() && ByvalParmDbgValues.empty() && DbgLabels.empty();
   }
 
   ArrayRef<SDDbgValue*> getSDDbgValues(const SDNode *Node) const {
     auto I = DbgValMap.find(Node);
     if (I != DbgValMap.end())
       return I->second;
     return ArrayRef<SDDbgValue*>();
   }
 
   using DbgIterator = SmallVectorImpl<SDDbgValue*>::iterator;
   using DbgLabelIterator = SmallVectorImpl<SDDbgLabel*>::iterator;
 
   DbgIterator DbgBegin() { return DbgValues.begin(); }
   DbgIterator DbgEnd()   { return DbgValues.end(); }
   DbgIterator ByvalParmDbgBegin() { return ByvalParmDbgValues.begin(); }
   DbgIterator ByvalParmDbgEnd()   { return ByvalParmDbgValues.end(); }
   DbgLabelIterator DbgLabelBegin() { return DbgLabels.begin(); }
   DbgLabelIterator DbgLabelEnd()   { return DbgLabels.end(); }
 };
 
 void checkForCycles(const SelectionDAG *DAG, bool force = false);
 
 /// This is used to represent a portion of an LLVM function in a low-level
 /// Data Dependence DAG representation suitable for instruction selection.
 /// This DAG is constructed as the first step of instruction selection in order
 /// to allow implementation of machine specific optimizations
 /// and code simplifications.
 ///
 /// The representation used by the SelectionDAG is a target-independent
 /// representation, which has some similarities to the GCC RTL representation,
 /// but is significantly more simple, powerful, and is a graph form instead of a
 /// linear form.
 ///
 class SelectionDAG {
   const TargetMachine &TM;
   const SelectionDAGTargetInfo *TSI = nullptr;
   const TargetLowering *TLI = nullptr;
   const TargetLibraryInfo *LibInfo = nullptr;
   const FunctionVarLocs *FnVarLocs = nullptr;
   MachineFunction *MF;
   MachineFunctionAnalysisManager *MFAM = nullptr;
   Pass *SDAGISelPass = nullptr;
   LLVMContext *Context;
   CodeGenOptLevel OptLevel;
 
   UniformityInfo *UA = nullptr;
   FunctionLoweringInfo * FLI = nullptr;
 
   /// The function-level optimization remark emitter.  Used to emit remarks
   /// whenever manipulating the DAG.
   OptimizationRemarkEmitter *ORE;
 
   ProfileSummaryInfo *PSI = nullptr;
   BlockFrequencyInfo *BFI = nullptr;
   MachineModuleInfo *MMI = nullptr;
 
   /// Extended EVTs used for single value VTLists.
   std::set<EVT, EVT::compareRawBits> EVTs;
 
   /// List of non-single value types.
   FoldingSet<SDVTListNode> VTListMap;
 
   /// Pool allocation for misc. objects that are created once per SelectionDAG.
   BumpPtrAllocator Allocator;
 
   /// The starting token.
   SDNode EntryNode;
 
   /// The root of the entire DAG.
   SDValue Root;
 
   /// A linked list of nodes in the current DAG.
   ilist<SDNode> AllNodes;
 
   /// The AllocatorType for allocating SDNodes. We use
   /// pool allocation with recycling.
   using NodeAllocatorType = RecyclingAllocator<BumpPtrAllocator, SDNode,
                                                sizeof(LargestSDNode),
                                                alignof(MostAlignedSDNode)>;
 
   /// Pool allocation for nodes.
   NodeAllocatorType NodeAllocator;
 
   /// This structure is used to memoize nodes, automatically performing
   /// CSE with existing nodes when a duplicate is requested.
   FoldingSet<SDNode> CSEMap;
 
   /// Pool allocation for machine-opcode SDNode operands.
   BumpPtrAllocator OperandAllocator;
   ArrayRecycler<SDUse> OperandRecycler;
 
   /// Tracks dbg_value and dbg_label information through SDISel.
   SDDbgInfo *DbgInfo;
 
   using CallSiteInfo = MachineFunction::CallSiteInfo;
   using CalledGlobalInfo = MachineFunction::CalledGlobalInfo;
 
   struct NodeExtraInfo {
     CallSiteInfo CSInfo;
     MDNode *HeapAllocSite = nullptr;
     MDNode *PCSections = nullptr;
     MDNode *MMRA = nullptr;
     CalledGlobalInfo CalledGlobal{};
     bool NoMerge = false;
   };
   /// Out-of-line extra information for SDNodes.
   DenseMap<const SDNode *, NodeExtraInfo> SDEI;
 
   /// PersistentId counter to be used when inserting the next
   /// SDNode to this SelectionDAG. We do not place that under
   /// `#if LLVM_ENABLE_ABI_BREAKING_CHECKS` intentionally because
   /// it adds unneeded complexity without noticeable
   /// benefits (see discussion with @thakis in D120714).
   uint16_t NextPersistentId = 0;
 
 public:
   /// Clients of various APIs that cause global effects on
   /// the DAG can optionally implement this interface.  This allows the clients
   /// to handle the various sorts of updates that happen.
   ///
   /// A DAGUpdateListener automatically registers itself with DAG when it is
   /// constructed, and removes itself when destroyed in RAII fashion.
   struct DAGUpdateListener {
     DAGUpdateListener *const Next;
     SelectionDAG &DAG;
 
     explicit DAGUpdateListener(SelectionDAG &D)
       : Next(D.UpdateListeners), DAG(D) {
       DAG.UpdateListeners = this;
     }
 
     virtual ~DAGUpdateListener() {
       assert(DAG.UpdateListeners == this &&
              "DAGUpdateListeners must be destroyed in LIFO order");
       DAG.UpdateListeners = Next;
     }
 
     /// The node N that was deleted and, if E is not null, an
     /// equivalent node E that replaced it.
     virtual void NodeDeleted(SDNode *N, SDNode *E);
 
     /// The node N that was updated.
     virtual void NodeUpdated(SDNode *N);
 
     /// The node N that was inserted.
     virtual void NodeInserted(SDNode *N);
   };
 
   struct DAGNodeDeletedListener : public DAGUpdateListener {
     std::function<void(SDNode *, SDNode *)> Callback;
 
     DAGNodeDeletedListener(SelectionDAG &DAG,
                            std::function<void(SDNode *, SDNode *)> Callback)
         : DAGUpdateListener(DAG), Callback(std::move(Callback)) {}
 
     void NodeDeleted(SDNode *N, SDNode *E) override { Callback(N, E); }
 
    private:
     virtual void anchor();
   };
 
   struct DAGNodeInsertedListener : public DAGUpdateListener {
     std::function<void(SDNode *)> Callback;
 
     DAGNodeInsertedListener(SelectionDAG &DAG,
                             std::function<void(SDNode *)> Callback)
         : DAGUpdateListener(DAG), Callback(std::move(Callback)) {}
 
     void NodeInserted(SDNode *N) override { Callback(N); }
 
   private:
     virtual void anchor();
   };
 
   /// Help to insert SDNodeFlags automatically in transforming. Use
   /// RAII to save and resume flags in current scope.
   class FlagInserter {
     SelectionDAG &DAG;
     SDNodeFlags Flags;
     FlagInserter *LastInserter;
 
   public:
     FlagInserter(SelectionDAG &SDAG, SDNodeFlags Flags)
         : DAG(SDAG), Flags(Flags),
           LastInserter(SDAG.getFlagInserter()) {
       SDAG.setFlagInserter(this);
     }
     FlagInserter(SelectionDAG &SDAG, SDNode *N)
         : FlagInserter(SDAG, N->getFlags()) {}
 
     FlagInserter(const FlagInserter &) = delete;
     FlagInserter &operator=(const FlagInserter &) = delete;
     ~FlagInserter() { DAG.setFlagInserter(LastInserter); }
 
     SDNodeFlags getFlags() const { return Flags; }
   };
 
   /// When true, additional steps are taken to
   /// ensure that getConstant() and similar functions return DAG nodes that
   /// have legal types. This is important after type legalization since
   /// any illegally typed nodes generated after this point will not experience
   /// type legalization.
   bool NewNodesMustHaveLegalTypes = false;
 
 private:
   /// DAGUpdateListener is a friend so it can manipulate the listener stack.
   friend struct DAGUpdateListener;
 
   /// Linked list of registered DAGUpdateListener instances.
   /// This stack is maintained by DAGUpdateListener RAII.
   DAGUpdateListener *UpdateListeners = nullptr;
 
   /// Implementation of setSubgraphColor.
   /// Return whether we had to truncate the search.
   bool setSubgraphColorHelper(SDNode *N, const char *Color,
                               DenseSet<SDNode *> &visited,
                               int level, bool &printed);
 
   template <typename SDNodeT, typename... ArgTypes>
   SDNodeT *newSDNode(ArgTypes &&... Args) {
     return new (NodeAllocator.template Allocate<SDNodeT>())
         SDNodeT(std::forward<ArgTypes>(Args)...);
   }
 
   /// Build a synthetic SDNodeT with the given args and extract its subclass
   /// data as an integer (e.g. for use in a folding set).
   ///
   /// The args to this function are the same as the args to SDNodeT's
   /// constructor, except the second arg (assumed to be a const DebugLoc&) is
   /// omitted.
   template <typename SDNodeT, typename... ArgTypes>
   static uint16_t getSyntheticNodeSubclassData(unsigned IROrder,
                                                ArgTypes &&... Args) {
     // The compiler can reduce this expression to a constant iff we pass an
     // empty DebugLoc.  Thankfully, the debug location doesn't have any bearing
     // on the subclass data.
     return SDNodeT(IROrder, DebugLoc(), std::forward<ArgTypes>(Args)...)
         .getRawSubclassData();
   }
 
   template <typename SDNodeTy>
   static uint16_t getSyntheticNodeSubclassData(unsigned Opc, unsigned Order,
                                                 SDVTList VTs, EVT MemoryVT,
                                                 MachineMemOperand *MMO) {
     return SDNodeTy(Opc, Order, DebugLoc(), VTs, MemoryVT, MMO)
          .getRawSubclassData();
   }
 
   void createOperands(SDNode *Node, ArrayRef<SDValue> Vals);
 
   void removeOperands(SDNode *Node) {
     if (!Node->OperandList)
       return;
     OperandRecycler.deallocate(
         ArrayRecycler<SDUse>::Capacity::get(Node->NumOperands),
         Node->OperandList);
     Node->NumOperands = 0;
     Node->OperandList = nullptr;
   }
   void CreateTopologicalOrder(std::vector<SDNode*>& Order);
 
 public:
   // Maximum depth for recursive analysis such as computeKnownBits, etc.
   static constexpr unsigned MaxRecursionDepth = 6;
 
   // Returns the maximum steps for SDNode->hasPredecessor() like searches.
   static unsigned getHasPredecessorMaxSteps();
 
   explicit SelectionDAG(const TargetMachine &TM, CodeGenOptLevel);
   SelectionDAG(const SelectionDAG &) = delete;
   SelectionDAG &operator=(const SelectionDAG &) = delete;
   ~SelectionDAG();
 
   /// Prepare this SelectionDAG to process code in the given MachineFunction.
   void init(MachineFunction &NewMF, OptimizationRemarkEmitter &NewORE,
             Pass *PassPtr, const TargetLibraryInfo *LibraryInfo,
             UniformityInfo *UA, ProfileSummaryInfo *PSIin,
             BlockFrequencyInfo *BFIin, MachineModuleInfo &MMI,
             FunctionVarLocs const *FnVarLocs);
 
   void init(MachineFunction &NewMF, OptimizationRemarkEmitter &NewORE,
             MachineFunctionAnalysisManager &AM,
             const TargetLibraryInfo *LibraryInfo, UniformityInfo *UA,
             ProfileSummaryInfo *PSIin, BlockFrequencyInfo *BFIin,
             MachineModuleInfo &MMI, FunctionVarLocs const *FnVarLocs) {
     init(NewMF, NewORE, nullptr, LibraryInfo, UA, PSIin, BFIin, MMI, FnVarLocs);
     MFAM = &AM;
   }
 
   void setFunctionLoweringInfo(FunctionLoweringInfo * FuncInfo) {
     FLI = FuncInfo;
   }
 
   /// Clear state and free memory necessary to make this
   /// SelectionDAG ready to process a new block.
   void clear();
 
   MachineFunction &getMachineFunction() const { return *MF; }
   const Pass *getPass() const { return SDAGISelPass; }
   MachineFunctionAnalysisManager *getMFAM() { return MFAM; }
 
   CodeGenOptLevel getOptLevel() const { return OptLevel; }
   const DataLayout &getDataLayout() const { return MF->getDataLayout(); }
   const TargetMachine &getTarget() const { return TM; }
   const TargetSubtargetInfo &getSubtarget() const { return MF->getSubtarget(); }
   template <typename STC> const STC &getSubtarget() const {
     return MF->getSubtarget<STC>();
   }
   const TargetLowering &getTargetLoweringInfo() const { return *TLI; }
   const TargetLibraryInfo &getLibInfo() const { return *LibInfo; }
   const SelectionDAGTargetInfo &getSelectionDAGInfo() const { return *TSI; }
   const UniformityInfo *getUniformityInfo() const { return UA; }
   /// Returns the result of the AssignmentTrackingAnalysis pass if it's
   /// available, otherwise return nullptr.
   const FunctionVarLocs *getFunctionVarLocs() const { return FnVarLocs; }
   LLVMContext *getContext() const { return Context; }
   OptimizationRemarkEmitter &getORE() const { return *ORE; }
   ProfileSummaryInfo *getPSI() const { return PSI; }
   BlockFrequencyInfo *getBFI() const { return BFI; }
   MachineModuleInfo *getMMI() const { return MMI; }
 
   FlagInserter *getFlagInserter() { return Inserter; }
   void setFlagInserter(FlagInserter *FI) { Inserter = FI; }
 
   /// Just dump dot graph to a user-provided path and title.
   /// This doesn't open the dot viewer program and
   /// helps visualization when outside debugging session.
   /// FileName expects absolute path. If provided
   /// without any path separators then the file
   /// will be created in the current directory.
   /// Error will be emitted if the path is insane.
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
   LLVM_DUMP_METHOD void dumpDotGraph(const Twine &FileName, const Twine &Title);
 #endif
 
   /// Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
   void viewGraph(const std::string &Title);
   void viewGraph();
 
 #if LLVM_ENABLE_ABI_BREAKING_CHECKS
   std::map<const SDNode *, std::string> NodeGraphAttrs;
 #endif
 
   /// Clear all previously defined node graph attributes.
   /// Intended to be used from a debugging tool (eg. gdb).
   void clearGraphAttrs();
 
   /// Set graph attributes for a node. (eg. "color=red".)
   void setGraphAttrs(const SDNode *N, const char *Attrs);
 
   /// Get graph attributes for a node. (eg. "color=red".)
   /// Used from getNodeAttributes.
   std::string getGraphAttrs(const SDNode *N) const;
 
   /// Convenience for setting node color attribute.
   void setGraphColor(const SDNode *N, const char *Color);
 
   /// Convenience for setting subgraph color attribute.
   void setSubgraphColor(SDNode *N, const char *Color);
 
   using allnodes_const_iterator = ilist<SDNode>::const_iterator;
 
   allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
   allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
 
   using allnodes_iterator = ilist<SDNode>::iterator;
 
   allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
   allnodes_iterator allnodes_end() { return AllNodes.end(); }
 
   ilist<SDNode>::size_type allnodes_size() const {
     return AllNodes.size();
   }
 
   iterator_range<allnodes_iterator> allnodes() {
     return make_range(allnodes_begin(), allnodes_end());
   }
   iterator_range<allnodes_const_iterator> allnodes() const {
     return make_range(allnodes_begin(), allnodes_end());
   }
 
   /// Return the root tag of the SelectionDAG.
   const SDValue &getRoot() const { return Root; }
 
   /// Return the token chain corresponding to the entry of the function.
   SDValue getEntryNode() const {
     return SDValue(const_cast<SDNode *>(&EntryNode), 0);
   }
 
   /// Set the current root tag of the SelectionDAG.
   ///
   const SDValue &setRoot(SDValue N) {
     assert((!N.getNode() || N.getValueType() == MVT::Other) &&
            "DAG root value is not a chain!");
     if (N.getNode())
       checkForCycles(N.getNode(), this);
     Root = N;
     if (N.getNode())
       checkForCycles(this);
     return Root;
   }
 
 #if !defined(NDEBUG) && LLVM_ENABLE_ABI_BREAKING_CHECKS
   void VerifyDAGDivergence();
 #endif
 
   /// This iterates over the nodes in the SelectionDAG, folding
   /// certain types of nodes together, or eliminating superfluous nodes.  The
   /// Level argument controls whether Combine is allowed to produce nodes and
   /// types that are illegal on the target.
   void Combine(CombineLevel Level, BatchAAResults *BatchAA,
                CodeGenOptLevel OptLevel);
 
   /// This transforms the SelectionDAG into a SelectionDAG that
   /// only uses types natively supported by the target.
   /// Returns "true" if it made any changes.
   ///
   /// Note that this is an involved process that may invalidate pointers into
   /// the graph.
   bool LegalizeTypes();
 
   /// This transforms the SelectionDAG into a SelectionDAG that is
   /// compatible with the target instruction selector, as indicated by the
   /// TargetLowering object.
   ///
   /// Note that this is an involved process that may invalidate pointers into
   /// the graph.
   void Legalize();
 
   /// Transforms a SelectionDAG node and any operands to it into a node
   /// that is compatible with the target instruction selector, as indicated by
   /// the TargetLowering object.
   ///
   /// \returns true if \c N is a valid, legal node after calling this.
   ///
   /// This essentially runs a single recursive walk of the \c Legalize process
   /// over the given node (and its operands). This can be used to incrementally
   /// legalize the DAG. All of the nodes which are directly replaced,
   /// potentially including N, are added to the output parameter \c
   /// UpdatedNodes so that the delta to the DAG can be understood by the
   /// caller.
   ///
   /// When this returns false, N has been legalized in a way that make the
   /// pointer passed in no longer valid. It may have even been deleted from the
   /// DAG, and so it shouldn't be used further. When this returns true, the
   /// N passed in is a legal node, and can be immediately processed as such.
   /// This may still have done some work on the DAG, and will still populate
   /// UpdatedNodes with any new nodes replacing those originally in the DAG.
   bool LegalizeOp(SDNode *N, SmallSetVector<SDNode *, 16> &UpdatedNodes);
 
   /// This transforms the SelectionDAG into a SelectionDAG
   /// that only uses vector math operations supported by the target.  This is
   /// necessary as a separate step from Legalize because unrolling a vector
   /// operation can introduce illegal types, which requires running
   /// LegalizeTypes again.
   ///
   /// This returns true if it made any changes; in that case, LegalizeTypes
   /// is called again before Legalize.
   ///
   /// Note that this is an involved process that may invalidate pointers into
   /// the graph.
   bool LegalizeVectors();
 
   /// This method deletes all unreachable nodes in the SelectionDAG.
   void RemoveDeadNodes();
 
   /// Remove the specified node from the system.  This node must
   /// have no referrers.
   void DeleteNode(SDNode *N);
 
   /// Return an SDVTList that represents the list of values specified.
   SDVTList getVTList(EVT VT);
   SDVTList getVTList(EVT VT1, EVT VT2);
   SDVTList getVTList(EVT VT1, EVT VT2, EVT VT3);
   SDVTList getVTList(EVT VT1, EVT VT2, EVT VT3, EVT VT4);
   SDVTList getVTList(ArrayRef<EVT> VTs);
 
   //===--------------------------------------------------------------------===//
   // Node creation methods.
 
   /// Create a ConstantSDNode wrapping a constant value.
   /// If VT is a vector type, the constant is splatted into a BUILD_VECTOR.
   ///
   /// If only legal types can be produced, this does the necessary
   /// transformations (e.g., if the vector element type is illegal).
   /// @{
   SDValue getConstant(uint64_t Val, const SDLoc &DL, EVT VT,
                       bool isTarget = false, bool isOpaque = false);
   SDValue getConstant(const APInt &Val, const SDLoc &DL, EVT VT,
                       bool isTarget = false, bool isOpaque = false);
 
   SDValue getSignedConstant(int64_t Val, const SDLoc &DL, EVT VT,
                             bool isTarget = false, bool isOpaque = false);
 
   SDValue getAllOnesConstant(const SDLoc &DL, EVT VT, bool IsTarget = false,
                              bool IsOpaque = false);
 
   SDValue getConstant(const ConstantInt &Val, const SDLoc &DL, EVT VT,
                       bool isTarget = false, bool isOpaque = false);
   SDValue getIntPtrConstant(uint64_t Val, const SDLoc &DL,
                             bool isTarget = false);
   SDValue getShiftAmountConstant(uint64_t Val, EVT VT, const SDLoc &DL);
   SDValue getShiftAmountConstant(const APInt &Val, EVT VT, const SDLoc &DL);
   SDValue getVectorIdxConstant(uint64_t Val, const SDLoc &DL,
                                bool isTarget = false);
 
   SDValue getTargetConstant(uint64_t Val, const SDLoc &DL, EVT VT,
                             bool isOpaque = false) {
     return getConstant(Val, DL, VT, true, isOpaque);
   }
   SDValue getTargetConstant(const APInt &Val, const SDLoc &DL, EVT VT,
                             bool isOpaque = false) {
     return getConstant(Val, DL, VT, true, isOpaque);
   }
   SDValue getTargetConstant(const ConstantInt &Val, const SDLoc &DL, EVT VT,
                             bool isOpaque = false) {
     return getConstant(Val, DL, VT, true, isOpaque);
   }
   SDValue getSignedTargetConstant(int64_t Val, const SDLoc &DL, EVT VT,
                                   bool isOpaque = false) {
     return getSignedConstant(Val, DL, VT, true, isOpaque);
   }
 
   /// Create a true or false constant of type \p VT using the target's
   /// BooleanContent for type \p OpVT.
   SDValue getBoolConstant(bool V, const SDLoc &DL, EVT VT, EVT OpVT);
   /// @}
 
   /// Create a ConstantFPSDNode wrapping a constant value.
   /// If VT is a vector type, the constant is splatted into a BUILD_VECTOR.
   ///
   /// If only legal types can be produced, this does the necessary
   /// transformations (e.g., if the vector element type is illegal).
   /// The forms that take a double should only be used for simple constants
   /// that can be exactly represented in VT.  No checks are made.
   /// @{
   SDValue getConstantFP(double Val, const SDLoc &DL, EVT VT,
                         bool isTarget = false);
   SDValue getConstantFP(const APFloat &Val, const SDLoc &DL, EVT VT,
                         bool isTarget = false);
   SDValue getConstantFP(const ConstantFP &V, const SDLoc &DL, EVT VT,
                         bool isTarget = false);
   SDValue getTargetConstantFP(double Val, const SDLoc &DL, EVT VT) {
     return getConstantFP(Val, DL, VT, true);
   }
   SDValue getTargetConstantFP(const APFloat &Val, const SDLoc &DL, EVT VT) {
     return getConstantFP(Val, DL, VT, true);
   }
   SDValue getTargetConstantFP(const ConstantFP &Val, const SDLoc &DL, EVT VT) {
     return getConstantFP(Val, DL, VT, true);
   }
   /// @}
 
   SDValue getGlobalAddress(const GlobalValue *GV, const SDLoc &DL, EVT VT,
                            int64_t offset = 0, bool isTargetGA = false,
                            unsigned TargetFlags = 0);
   SDValue getTargetGlobalAddress(const GlobalValue *GV, const SDLoc &DL, EVT VT,
                                  int64_t offset = 0, unsigned TargetFlags = 0) {
     return getGlobalAddress(GV, DL, VT, offset, true, TargetFlags);
   }
   SDValue getFrameIndex(int FI, EVT VT, bool isTarget = false);
   SDValue getTargetFrameIndex(int FI, EVT VT) {
     return getFrameIndex(FI, VT, true);
   }
   SDValue getJumpTable(int JTI, EVT VT, bool isTarget = false,
                        unsigned TargetFlags = 0);
   SDValue getTargetJumpTable(int JTI, EVT VT, unsigned TargetFlags = 0) {
     return getJumpTable(JTI, VT, true, TargetFlags);
   }
   SDValue getJumpTableDebugInfo(int JTI, SDValue Chain, const SDLoc &DL);
   SDValue getConstantPool(const Constant *C, EVT VT,
                           MaybeAlign Align = std::nullopt, int Offs = 0,
                           bool isT = false, unsigned TargetFlags = 0);
   SDValue getTargetConstantPool(const Constant *C, EVT VT,
                                 MaybeAlign Align = std::nullopt, int Offset = 0,
                                 unsigned TargetFlags = 0) {
     return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
   }
   SDValue getConstantPool(MachineConstantPoolValue *C, EVT VT,
                           MaybeAlign Align = std::nullopt, int Offs = 0,
                           bool isT = false, unsigned TargetFlags = 0);
   SDValue getTargetConstantPool(MachineConstantPoolValue *C, EVT VT,
                                 MaybeAlign Align = std::nullopt, int Offset = 0,
                                 unsigned TargetFlags = 0) {
     return getConstantPool(C, VT, Align, Offset, true, TargetFlags);
   }
   // When generating a branch to a BB, we don't in general know enough
   // to provide debug info for the BB at that time, so keep this one around.
   SDValue getBasicBlock(MachineBasicBlock *MBB);
   SDValue getExternalSymbol(const char *Sym, EVT VT);
   SDValue getTargetExternalSymbol(const char *Sym, EVT VT,
                                   unsigned TargetFlags = 0);
   SDValue getMCSymbol(MCSymbol *Sym, EVT VT);
 
   SDValue getValueType(EVT);
   SDValue getRegister(Register Reg, EVT VT);
   SDValue getRegisterMask(const uint32_t *RegMask);
   SDValue getEHLabel(const SDLoc &dl, SDValue Root, MCSymbol *Label);
   SDValue getLabelNode(unsigned Opcode, const SDLoc &dl, SDValue Root,
                        MCSymbol *Label);
   SDValue getBlockAddress(const BlockAddress *BA, EVT VT, int64_t Offset = 0,
                           bool isTarget = false, unsigned TargetFlags = 0);
   SDValue getTargetBlockAddress(const BlockAddress *BA, EVT VT,
                                 int64_t Offset = 0, unsigned TargetFlags = 0) {
     return getBlockAddress(BA, VT, Offset, true, TargetFlags);
   }
 
   SDValue getCopyToReg(SDValue Chain, const SDLoc &dl, Register Reg,
                        SDValue N) {
     return getNode(ISD::CopyToReg, dl, MVT::Other, Chain,
                    getRegister(Reg, N.getValueType()), N);
   }
 
   // This version of the getCopyToReg method takes an extra operand, which
   // indicates that there is potentially an incoming glue value (if Glue is not
   // null) and that there should be a glue result.
   SDValue getCopyToReg(SDValue Chain, const SDLoc &dl, Register Reg, SDValue N,
                        SDValue Glue) {
     SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
     SDValue Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Glue };
     return getNode(ISD::CopyToReg, dl, VTs,
                    ArrayRef(Ops, Glue.getNode() ? 4 : 3));
   }
 
   // Similar to last getCopyToReg() except parameter Reg is a SDValue
   SDValue getCopyToReg(SDValue Chain, const SDLoc &dl, SDValue Reg, SDValue N,
                        SDValue Glue) {
     SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
     SDValue Ops[] = { Chain, Reg, N, Glue };
     return getNode(ISD::CopyToReg, dl, VTs,
                    ArrayRef(Ops, Glue.getNode() ? 4 : 3));
   }
 
   SDValue getCopyFromReg(SDValue Chain, const SDLoc &dl, Register Reg, EVT VT) {
     SDVTList VTs = getVTList(VT, MVT::Other);
     SDValue Ops[] = { Chain, getRegister(Reg, VT) };
     return getNode(ISD::CopyFromReg, dl, VTs, Ops);
   }
 
   // This version of the getCopyFromReg method takes an extra operand, which
   // indicates that there is potentially an incoming glue value (if Glue is not
   // null) and that there should be a glue result.
   SDValue getCopyFromReg(SDValue Chain, const SDLoc &dl, Register Reg, EVT VT,
                          SDValue Glue) {
     SDVTList VTs = getVTList(VT, MVT::Other, MVT::Glue);
     SDValue Ops[] = { Chain, getRegister(Reg, VT), Glue };
     return getNode(ISD::CopyFromReg, dl, VTs,
                    ArrayRef(Ops, Glue.getNode() ? 3 : 2));
   }
 
   SDValue getCondCode(ISD::CondCode Cond);
 
   /// Return an ISD::VECTOR_SHUFFLE node. The number of elements in VT,
   /// which must be a vector type, must match the number of mask elements
   /// NumElts. An integer mask element equal to -1 is treated as undefined.
   SDValue getVectorShuffle(EVT VT, const SDLoc &dl, SDValue N1, SDValue N2,
                            ArrayRef<int> Mask);
 
   /// Return an ISD::BUILD_VECTOR node. The number of elements in VT,
   /// which must be a vector type, must match the number of operands in Ops.
   /// The operands must have the same type as (or, for integers, a type wider
   /// than) VT's element type.
   SDValue getBuildVector(EVT VT, const SDLoc &DL, ArrayRef<SDValue> Ops) {
     // VerifySDNode (via InsertNode) checks BUILD_VECTOR later.
     return getNode(ISD::BUILD_VECTOR, DL, VT, Ops);
   }
 
   /// Return an ISD::BUILD_VECTOR node. The number of elements in VT,
   /// which must be a vector type, must match the number of operands in Ops.
   /// The operands must have the same type as (or, for integers, a type wider
   /// than) VT's element type.
   SDValue getBuildVector(EVT VT, const SDLoc &DL, ArrayRef<SDUse> Ops) {
     // VerifySDNode (via InsertNode) checks BUILD_VECTOR later.
     return getNode(ISD::BUILD_VECTOR, DL, VT, Ops);
   }
 
   /// Return a splat ISD::BUILD_VECTOR node, consisting of Op splatted to all
   /// elements. VT must be a vector type. Op's type must be the same as (or,
   /// for integers, a type wider than) VT's element type.
   SDValue getSplatBuildVector(EVT VT, const SDLoc &DL, SDValue Op) {
     // VerifySDNode (via InsertNode) checks BUILD_VECTOR later.
     if (Op.getOpcode() == ISD::UNDEF) {
       assert((VT.getVectorElementType() == Op.getValueType() ||
               (VT.isInteger() &&
                VT.getVectorElementType().bitsLE(Op.getValueType()))) &&
              "A splatted value must have a width equal or (for integers) "
              "greater than the vector element type!");
       return getNode(ISD::UNDEF, SDLoc(), VT);
     }
 
     SmallVector<SDValue, 16> Ops(VT.getVectorNumElements(), Op);
     return getNode(ISD::BUILD_VECTOR, DL, VT, Ops);
   }
 
   // Return a splat ISD::SPLAT_VECTOR node, consisting of Op splatted to all
   // elements.
   SDValue getSplatVector(EVT VT, const SDLoc &DL, SDValue Op) {
     if (Op.getOpcode() == ISD::UNDEF) {
       assert((VT.getVectorElementType() == Op.getValueType() ||
               (VT.isInteger() &&
                VT.getVectorElementType().bitsLE(Op.getValueType()))) &&
              "A splatted value must have a width equal or (for integers) "
              "greater than the vector element type!");
       return getNode(ISD::UNDEF, SDLoc(), VT);
     }
     return getNode(ISD::SPLAT_VECTOR, DL, VT, Op);
   }
 
   /// Returns a node representing a splat of one value into all lanes
   /// of the provided vector type.  This is a utility which returns
   /// either a BUILD_VECTOR or SPLAT_VECTOR depending on the
   /// scalability of the desired vector type.
   SDValue getSplat(EVT VT, const SDLoc &DL, SDValue Op) {
     assert(VT.isVector() && "Can't splat to non-vector type");
     return VT.isScalableVector() ?
       getSplatVector(VT, DL, Op) : getSplatBuildVector(VT, DL, Op);
   }
 
   /// Returns a vector of type ResVT whose elements contain the linear sequence
   ///   <0, Step, Step * 2, Step * 3, ...>
   SDValue getStepVector(const SDLoc &DL, EVT ResVT, const APInt &StepVal);
 
   /// Returns a vector of type ResVT whose elements contain the linear sequence
   ///   <0, 1, 2, 3, ...>
   SDValue getStepVector(const SDLoc &DL, EVT ResVT);
 
   /// Returns an ISD::VECTOR_SHUFFLE node semantically equivalent to
   /// the shuffle node in input but with swapped operands.
   ///
   /// Example: shuffle A, B, <0,5,2,7> -> shuffle B, A, <4,1,6,3>
   SDValue getCommutedVectorShuffle(const ShuffleVectorSDNode &SV);
 
   /// Convert Op, which must be of float type, to the
   /// float type VT, by either extending or rounding (by truncation).
   SDValue getFPExtendOrRound(SDValue Op, const SDLoc &DL, EVT VT);
 
   /// Convert Op, which must be a STRICT operation of float type, to the
   /// float type VT, by either extending or rounding (by truncation).
   std::pair<SDValue, SDValue>
   getStrictFPExtendOrRound(SDValue Op, SDValue Chain, const SDLoc &DL, EVT VT);
 
   /// Convert *_EXTEND_VECTOR_INREG to *_EXTEND opcode.
   static unsigned getOpcode_EXTEND(unsigned Opcode) {
     switch (Opcode) {
     case ISD::ANY_EXTEND:
     case ISD::ANY_EXTEND_VECTOR_INREG:
       return ISD::ANY_EXTEND;
     case ISD::ZERO_EXTEND:
     case ISD::ZERO_EXTEND_VECTOR_INREG:
       return ISD::ZERO_EXTEND;
     case ISD::SIGN_EXTEND:
     case ISD::SIGN_EXTEND_VECTOR_INREG:
       return ISD::SIGN_EXTEND;
     }
     llvm_unreachable("Unknown opcode");
   }
 
   /// Convert *_EXTEND to *_EXTEND_VECTOR_INREG opcode.
   static unsigned getOpcode_EXTEND_VECTOR_INREG(unsigned Opcode) {
     switch (Opcode) {
     case ISD::ANY_EXTEND:
     case ISD::ANY_EXTEND_VECTOR_INREG:
       return ISD::ANY_EXTEND_VECTOR_INREG;
     case ISD::ZERO_EXTEND:
     case ISD::ZERO_EXTEND_VECTOR_INREG:
       return ISD::ZERO_EXTEND_VECTOR_INREG;
     case ISD::SIGN_EXTEND:
     case ISD::SIGN_EXTEND_VECTOR_INREG:
       return ISD::SIGN_EXTEND_VECTOR_INREG;
     }
     llvm_unreachable("Unknown opcode");
   }
 
   /// Convert Op, which must be of integer type, to the
   /// integer type VT, by either any-extending or truncating it.
   SDValue getAnyExtOrTrunc(SDValue Op, const SDLoc &DL, EVT VT);
 
   /// Convert Op, which must be of integer type, to the
   /// integer type VT, by either sign-extending or truncating it.
   SDValue getSExtOrTrunc(SDValue Op, const SDLoc &DL, EVT VT);
 
   /// Convert Op, which must be of integer type, to the
   /// integer type VT, by either zero-extending or truncating it.
   SDValue getZExtOrTrunc(SDValue Op, const SDLoc &DL, EVT VT);
 
   /// Convert Op, which must be of integer type, to the
   /// integer type VT, by either any/sign/zero-extending (depending on IsAny /
   /// IsSigned) or truncating it.
   SDValue getExtOrTrunc(SDValue Op, const SDLoc &DL,
                         EVT VT, unsigned Opcode) {
     switch(Opcode) {
       case ISD::ANY_EXTEND:
         return getAnyExtOrTrunc(Op, DL, VT);
       case ISD::ZERO_EXTEND:
         return getZExtOrTrunc(Op, DL, VT);
       case ISD::SIGN_EXTEND:
         return getSExtOrTrunc(Op, DL, VT);
     }
     llvm_unreachable("Unsupported opcode");
   }
 
   /// Convert Op, which must be of integer type, to the
   /// integer type VT, by either sign/zero-extending (depending on IsSigned) or
   /// truncating it.
   SDValue getExtOrTrunc(bool IsSigned, SDValue Op, const SDLoc &DL, EVT VT) {
     return IsSigned ? getSExtOrTrunc(Op, DL, VT) : getZExtOrTrunc(Op, DL, VT);
   }
 
   /// Convert Op, which must be of integer type, to the
   /// integer type VT, by first bitcasting (from potential vector) to
   /// corresponding scalar type then either any-extending or truncating it.
   SDValue getBitcastedAnyExtOrTrunc(SDValue Op, const SDLoc &DL, EVT VT);
 
   /// Convert Op, which must be of integer type, to the
   /// integer type VT, by first bitcasting (from potential vector) to
   /// corresponding scalar type then either sign-extending or truncating it.
   SDValue getBitcastedSExtOrTrunc(SDValue Op, const SDLoc &DL, EVT VT);
 
   /// Convert Op, which must be of integer type, to the
   /// integer type VT, by first bitcasting (from potential vector) to
   /// corresponding scalar type then either zero-extending or truncating it.
   SDValue getBitcastedZExtOrTrunc(SDValue Op, const SDLoc &DL, EVT VT);
 
   /// Return the expression required to zero extend the Op
   /// value assuming it was the smaller SrcTy value.
   SDValue getZeroExtendInReg(SDValue Op, const SDLoc &DL, EVT VT);
 
   /// Return the expression required to zero extend the Op
   /// value assuming it was the smaller SrcTy value.
   SDValue getVPZeroExtendInReg(SDValue Op, SDValue Mask, SDValue EVL,
                                const SDLoc &DL, EVT VT);
 
   /// Convert Op, which must be of integer type, to the integer type VT, by
   /// either truncating it or performing either zero or sign extension as
   /// appropriate extension for the pointer's semantics.
   SDValue getPtrExtOrTrunc(SDValue Op, const SDLoc &DL, EVT VT);
 
   /// Return the expression required to extend the Op as a pointer value
   /// assuming it was the smaller SrcTy value. This may be either a zero extend
   /// or a sign extend.
   SDValue getPtrExtendInReg(SDValue Op, const SDLoc &DL, EVT VT);
 
   /// Convert Op, which must be of integer type, to the integer type VT,
   /// by using an extension appropriate for the target's
   /// BooleanContent for type OpVT or truncating it.
   SDValue getBoolExtOrTrunc(SDValue Op, const SDLoc &SL, EVT VT, EVT OpVT);
 
   /// Create negative operation as (SUB 0, Val).
   SDValue getNegative(SDValue Val, const SDLoc &DL, EVT VT);
 
   /// Create a bitwise NOT operation as (XOR Val, -1).
   SDValue getNOT(const SDLoc &DL, SDValue Val, EVT VT);
 
   /// Create a logical NOT operation as (XOR Val, BooleanOne).
   SDValue getLogicalNOT(const SDLoc &DL, SDValue Val, EVT VT);
 
   /// Create a vector-predicated logical NOT operation as (VP_XOR Val,
   /// BooleanOne, Mask, EVL).
   SDValue getVPLogicalNOT(const SDLoc &DL, SDValue Val, SDValue Mask,
                           SDValue EVL, EVT VT);
 
   /// Convert a vector-predicated Op, which must be an integer vector, to the
   /// vector-type VT, by performing either vector-predicated zext or truncating
   /// it. The Op will be returned as-is if Op and VT are vectors containing
   /// integer with same width.
   SDValue getVPZExtOrTrunc(const SDLoc &DL, EVT VT, SDValue Op, SDValue Mask,
                            SDValue EVL);
 
   /// Convert a vector-predicated Op, which must be of integer type, to the
   /// vector-type integer type VT, by either truncating it or performing either
   /// vector-predicated zero or sign extension as appropriate extension for the
   /// pointer's semantics. This function just redirects to getVPZExtOrTrunc
   /// right now.
   SDValue getVPPtrExtOrTrunc(const SDLoc &DL, EVT VT, SDValue Op, SDValue Mask,
                              SDValue EVL);
 
   /// Returns sum of the base pointer and offset.
   /// Unlike getObjectPtrOffset this does not set NoUnsignedWrap by default.
   SDValue getMemBasePlusOffset(SDValue Base, TypeSize Offset, const SDLoc &DL,
                                const SDNodeFlags Flags = SDNodeFlags());
   SDValue getMemBasePlusOffset(SDValue Base, SDValue Offset, const SDLoc &DL,
                                const SDNodeFlags Flags = SDNodeFlags());
 
   /// Create an add instruction with appropriate flags when used for
   /// addressing some offset of an object. i.e. if a load is split into multiple
   /// components, create an add nuw from the base pointer to the offset.
   SDValue getObjectPtrOffset(const SDLoc &SL, SDValue Ptr, TypeSize Offset) {
     return getMemBasePlusOffset(Ptr, Offset, SL, SDNodeFlags::NoUnsignedWrap);
   }
 
   SDValue getObjectPtrOffset(const SDLoc &SL, SDValue Ptr, SDValue Offset) {
     // The object itself can't wrap around the address space, so it shouldn't be
     // possible for the adds of the offsets to the split parts to overflow.
     return getMemBasePlusOffset(Ptr, Offset, SL, SDNodeFlags::NoUnsignedWrap);
   }
 
   /// Return a new CALLSEQ_START node, that starts new call frame, in which
   /// InSize bytes are set up inside CALLSEQ_START..CALLSEQ_END sequence and
   /// OutSize specifies part of the frame set up prior to the sequence.
   SDValue getCALLSEQ_START(SDValue Chain, uint64_t InSize, uint64_t OutSize,
                            const SDLoc &DL) {
     SDVTList VTs = getVTList(MVT::Other, MVT::Glue);
     SDValue Ops[] = { Chain,
                       getIntPtrConstant(InSize, DL, true),
                       getIntPtrConstant(OutSize, DL, true) };
     return getNode(ISD::CALLSEQ_START, DL, VTs, Ops);
   }
 
   /// Return a new CALLSEQ_END node, which always must have a
   /// glue result (to ensure it's not CSE'd).
   /// CALLSEQ_END does not have a useful SDLoc.
   SDValue getCALLSEQ_END(SDValue Chain, SDValue Op1, SDValue Op2,
                          SDValue InGlue, const SDLoc &DL) {
     SDVTList NodeTys = getVTList(MVT::Other, MVT::Glue);
     SmallVector<SDValue, 4> Ops;
     Ops.push_back(Chain);
     Ops.push_back(Op1);
     Ops.push_back(Op2);
     if (InGlue.getNode())
       Ops.push_back(InGlue);
     return getNode(ISD::CALLSEQ_END, DL, NodeTys, Ops);
   }
 
   SDValue getCALLSEQ_END(SDValue Chain, uint64_t Size1, uint64_t Size2,
                          SDValue Glue, const SDLoc &DL) {
     return getCALLSEQ_END(
         Chain, getIntPtrConstant(Size1, DL, /*isTarget=*/true),
         getIntPtrConstant(Size2, DL, /*isTarget=*/true), Glue, DL);
   }
 
   /// Return true if the result of this operation is always undefined.
   bool isUndef(unsigned Opcode, ArrayRef<SDValue> Ops);
 
   /// Return an UNDEF node. UNDEF does not have a useful SDLoc.
   SDValue getUNDEF(EVT VT) {
     return getNode(ISD::UNDEF, SDLoc(), VT);
   }
 
   /// Return a node that represents the runtime scaling 'MulImm * RuntimeVL'.
   SDValue getVScale(const SDLoc &DL, EVT VT, APInt MulImm,
                     bool ConstantFold = true);
 
   SDValue getElementCount(const SDLoc &DL, EVT VT, ElementCount EC,
                           bool ConstantFold = true);
 
   /// Return a GLOBAL_OFFSET_TABLE node. This does not have a useful SDLoc.
   SDValue getGLOBAL_OFFSET_TABLE(EVT VT) {
     return getNode(ISD::GLOBAL_OFFSET_TABLE, SDLoc(), VT);
   }
 
   /// Gets or creates the specified node.
   ///
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
                   ArrayRef<SDUse> Ops);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
                   ArrayRef<SDValue> Ops, const SDNodeFlags Flags);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, ArrayRef<EVT> ResultTys,
                   ArrayRef<SDValue> Ops);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList,
                   ArrayRef<SDValue> Ops, const SDNodeFlags Flags);
 
   // Use flags from current flag inserter.
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT,
                   ArrayRef<SDValue> Ops);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList,
                   ArrayRef<SDValue> Ops);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue Operand);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
                   SDValue N2);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
                   SDValue N2, SDValue N3);
 
   // Specialize based on number of operands.
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue Operand,
                   const SDNodeFlags Flags);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
                   SDValue N2, const SDNodeFlags Flags);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
                   SDValue N2, SDValue N3, const SDNodeFlags Flags);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
                   SDValue N2, SDValue N3, SDValue N4);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
                   SDValue N2, SDValue N3, SDValue N4, const SDNodeFlags Flags);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
                   SDValue N2, SDValue N3, SDValue N4, SDValue N5);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, EVT VT, SDValue N1,
                   SDValue N2, SDValue N3, SDValue N4, SDValue N5,
                   const SDNodeFlags Flags);
 
   // Specialize again based on number of operands for nodes with a VTList
   // rather than a single VT.
   SDValue getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList, SDValue N);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList, SDValue N1,
                   SDValue N2);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList, SDValue N1,
                   SDValue N2, SDValue N3);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList, SDValue N1,
                   SDValue N2, SDValue N3, SDValue N4);
   SDValue getNode(unsigned Opcode, const SDLoc &DL, SDVTList VTList, SDValue N1,
                   SDValue N2, SDValue N3, SDValue N4, SDValue N5);
 
   /// Compute a TokenFactor to force all the incoming stack arguments to be
   /// loaded from the stack. This is used in tail call lowering to protect
   /// stack arguments from being clobbered.
   SDValue getStackArgumentTokenFactor(SDValue Chain);
 
   /* \p CI if not null is the memset call being lowered.
    * \p OverrideTailCall is an optional parameter that can be used to override
    * the tail call optimization decision. */
   SDValue getMemcpy(SDValue Chain, const SDLoc &dl, SDValue Dst, SDValue Src,
                     SDValue Size, Align Alignment, bool isVol,
                     bool AlwaysInline, const CallInst *CI,
                     std::optional<bool> OverrideTailCall,
                     MachinePointerInfo DstPtrInfo,
                     MachinePointerInfo SrcPtrInfo,
                     const AAMDNodes &AAInfo = AAMDNodes(),
                     BatchAAResults *BatchAA = nullptr);
 
   /* \p CI if not null is the memset call being lowered.
    * \p OverrideTailCall is an optional parameter that can be used to override
    * the tail call optimization decision. */
   SDValue getMemmove(SDValue Chain, const SDLoc &dl, SDValue Dst, SDValue Src,
                      SDValue Size, Align Alignment, bool isVol,
                      const CallInst *CI, std::optional<bool> OverrideTailCall,
                      MachinePointerInfo DstPtrInfo,
                      MachinePointerInfo SrcPtrInfo,
                      const AAMDNodes &AAInfo = AAMDNodes(),
                      BatchAAResults *BatchAA = nullptr);
 
   SDValue getMemset(SDValue Chain, const SDLoc &dl, SDValue Dst, SDValue Src,
                     SDValue Size, Align Alignment, bool isVol,
                     bool AlwaysInline, const CallInst *CI,
                     MachinePointerInfo DstPtrInfo,
                     const AAMDNodes &AAInfo = AAMDNodes());
 
   SDValue getAtomicMemcpy(SDValue Chain, const SDLoc &dl, SDValue Dst,
                           SDValue Src, SDValue Size, Type *SizeTy,
                           unsigned ElemSz, bool isTailCall,
                           MachinePointerInfo DstPtrInfo,
                           MachinePointerInfo SrcPtrInfo);
 
   SDValue getAtomicMemmove(SDValue Chain, const SDLoc &dl, SDValue Dst,
                            SDValue Src, SDValue Size, Type *SizeTy,
                            unsigned ElemSz, bool isTailCall,
                            MachinePointerInfo DstPtrInfo,
                            MachinePointerInfo SrcPtrInfo);
 
   SDValue getAtomicMemset(SDValue Chain, const SDLoc &dl, SDValue Dst,
                           SDValue Value, SDValue Size, Type *SizeTy,
                           unsigned ElemSz, bool isTailCall,
                           MachinePointerInfo DstPtrInfo);
 
   /// Helper function to make it easier to build SetCC's if you just have an
   /// ISD::CondCode instead of an SDValue.
   SDValue getSetCC(const SDLoc &DL, EVT VT, SDValue LHS, SDValue RHS,
                    ISD::CondCode Cond, SDValue Chain = SDValue(),
                    bool IsSignaling = false) {
     assert(LHS.getValueType().isVector() == RHS.getValueType().isVector() &&
            "Vector/scalar operand type mismatch for setcc");
     assert(LHS.getValueType().isVector() == VT.isVector() &&
            "Vector/scalar result type mismatch for setcc");
     assert(Cond != ISD::SETCC_INVALID &&
            "Cannot create a setCC of an invalid node.");
     if (Chain)
       return getNode(IsSignaling ? ISD::STRICT_FSETCCS : ISD::STRICT_FSETCC, DL,
                      {VT, MVT::Other}, {Chain, LHS, RHS, getCondCode(Cond)});
     return getNode(ISD::SETCC, DL, VT, LHS, RHS, getCondCode(Cond));
   }
 
   /// Helper function to make it easier to build VP_SETCCs if you just have an
   /// ISD::CondCode instead of an SDValue.
   SDValue getSetCCVP(const SDLoc &DL, EVT VT, SDValue LHS, SDValue RHS,
                      ISD::CondCode Cond, SDValue Mask, SDValue EVL) {
     assert(LHS.getValueType().isVector() && RHS.getValueType().isVector() &&
            "Cannot compare scalars");
     assert(Cond != ISD::SETCC_INVALID &&
            "Cannot create a setCC of an invalid node.");
     return getNode(ISD::VP_SETCC, DL, VT, LHS, RHS, getCondCode(Cond), Mask,
                    EVL);
   }
 
   /// Helper function to make it easier to build Select's if you just have
   /// operands and don't want to check for vector.
   SDValue getSelect(const SDLoc &DL, EVT VT, SDValue Cond, SDValue LHS,
                     SDValue RHS, SDNodeFlags Flags = SDNodeFlags()) {
     assert(LHS.getValueType() == VT && RHS.getValueType() == VT &&
            "Cannot use select on differing types");
     auto Opcode = Cond.getValueType().isVector() ? ISD::VSELECT : ISD::SELECT;
     return getNode(Opcode, DL, VT, Cond, LHS, RHS, Flags);
   }
 
   /// Helper function to make it easier to build SelectCC's if you just have an
   /// ISD::CondCode instead of an SDValue.
   SDValue getSelectCC(const SDLoc &DL, SDValue LHS, SDValue RHS, SDValue True,
                       SDValue False, ISD::CondCode Cond) {
     return getNode(ISD::SELECT_CC, DL, True.getValueType(), LHS, RHS, True,
                    False, getCondCode(Cond));
   }
 
   /// Try to simplify a select/vselect into 1 of its operands or a constant.
   SDValue simplifySelect(SDValue Cond, SDValue TVal, SDValue FVal);
 
   /// Try to simplify a shift into 1 of its operands or a constant.
   SDValue simplifyShift(SDValue X, SDValue Y);
 
   /// Try to simplify a floating-point binary operation into 1 of its operands
   /// or a constant.
   SDValue simplifyFPBinop(unsigned Opcode, SDValue X, SDValue Y,
                           SDNodeFlags Flags);
 
   /// VAArg produces a result and token chain, and takes a pointer
   /// and a source value as input.
   SDValue getVAArg(EVT VT, const SDLoc &dl, SDValue Chain, SDValue Ptr,
                    SDValue SV, unsigned Align);
 
   /// Gets a node for an atomic cmpxchg op. There are two
   /// valid Opcodes. ISD::ATOMIC_CMO_SWAP produces the value loaded and a
   /// chain result. ISD::ATOMIC_CMP_SWAP_WITH_SUCCESS produces the value loaded,
   /// a success flag (initially i1), and a chain.
   SDValue getAtomicCmpSwap(unsigned Opcode, const SDLoc &dl, EVT MemVT,
                            SDVTList VTs, SDValue Chain, SDValue Ptr,
                            SDValue Cmp, SDValue Swp, MachineMemOperand *MMO);
 
   /// Gets a node for an atomic op, produces result (if relevant)
   /// and chain and takes 2 operands.
   SDValue getAtomic(unsigned Opcode, const SDLoc &dl, EVT MemVT, SDValue Chain,
                     SDValue Ptr, SDValue Val, MachineMemOperand *MMO);
 
   /// Gets a node for an atomic op, produces result and chain and
   /// takes 1 operand.
   SDValue getAtomic(unsigned Opcode, const SDLoc &dl, EVT MemVT, EVT VT,
                     SDValue Chain, SDValue Ptr, MachineMemOperand *MMO);
 
   /// Gets a node for an atomic op, produces result and chain and takes N
   /// operands.
   SDValue getAtomic(unsigned Opcode, const SDLoc &dl, EVT MemVT,
                     SDVTList VTList, ArrayRef<SDValue> Ops,
                     MachineMemOperand *MMO);
 
   /// Creates a MemIntrinsicNode that may produce a
   /// result and takes a list of operands. Opcode may be INTRINSIC_VOID,
   /// INTRINSIC_W_CHAIN, or a target-specific memory-referencing opcode
   // (see `SelectionDAGTargetInfo::isTargetMemoryOpcode`).
   SDValue getMemIntrinsicNode(
       unsigned Opcode, const SDLoc &dl, SDVTList VTList, ArrayRef<SDValue> Ops,
       EVT MemVT, MachinePointerInfo PtrInfo, Align Alignment,
       MachineMemOperand::Flags Flags = MachineMemOperand::MOLoad |
                                        MachineMemOperand::MOStore,
       LocationSize Size = 0, const AAMDNodes &AAInfo = AAMDNodes());
 
   inline SDValue getMemIntrinsicNode(
       unsigned Opcode, const SDLoc &dl, SDVTList VTList, ArrayRef<SDValue> Ops,
       EVT MemVT, MachinePointerInfo PtrInfo,
       MaybeAlign Alignment = std::nullopt,
       MachineMemOperand::Flags Flags = MachineMemOperand::MOLoad |
                                        MachineMemOperand::MOStore,
       LocationSize Size = 0, const AAMDNodes &AAInfo = AAMDNodes()) {
     // Ensure that codegen never sees alignment 0
     return getMemIntrinsicNode(Opcode, dl, VTList, Ops, MemVT, PtrInfo,
                                Alignment.value_or(getEVTAlign(MemVT)), Flags,
                                Size, AAInfo);
   }
 
   SDValue getMemIntrinsicNode(unsigned Opcode, const SDLoc &dl, SDVTList VTList,
                               ArrayRef<SDValue> Ops, EVT MemVT,
                               MachineMemOperand *MMO);
 
   /// Creates a LifetimeSDNode that starts (`IsStart==true`) or ends
   /// (`IsStart==false`) the lifetime of the portion of `FrameIndex` between
   /// offsets `Offset` and `Offset + Size`.
   SDValue getLifetimeNode(bool IsStart, const SDLoc &dl, SDValue Chain,
                           int FrameIndex, int64_t Size, int64_t Offset = -1);
 
   /// Creates a PseudoProbeSDNode with function GUID `Guid` and
   /// the index of the block `Index` it is probing, as well as the attributes
   /// `attr` of the probe.
   SDValue getPseudoProbeNode(const SDLoc &Dl, SDValue Chain, uint64_t Guid,
                              uint64_t Index, uint32_t Attr);
 
   /// Create a MERGE_VALUES node from the given operands.
   SDValue getMergeValues(ArrayRef<SDValue> Ops, const SDLoc &dl);
 
   /// Loads are not normal binary operators: their result type is not
   /// determined by their operands, and they produce a value AND a token chain.
   ///
   /// This function will set the MOLoad flag on MMOFlags, but you can set it if
   /// you want.  The MOStore flag must not be set.
   SDValue getLoad(EVT VT, const SDLoc &dl, SDValue Chain, SDValue Ptr,
                   MachinePointerInfo PtrInfo,
                   MaybeAlign Alignment = MaybeAlign(),
                   MachineMemOperand::Flags MMOFlags = MachineMemOperand::MONone,
                   const AAMDNodes &AAInfo = AAMDNodes(),
                   const MDNode *Ranges = nullptr);
   SDValue getLoad(EVT VT, const SDLoc &dl, SDValue Chain, SDValue Ptr,
                   MachineMemOperand *MMO);
   SDValue
   getExtLoad(ISD::LoadExtType ExtType, const SDLoc &dl, EVT VT, SDValue Chain,
              SDValue Ptr, MachinePointerInfo PtrInfo, EVT MemVT,
              MaybeAlign Alignment = MaybeAlign(),
              MachineMemOperand::Flags MMOFlags = MachineMemOperand::MONone,
              const AAMDNodes &AAInfo = AAMDNodes());
   SDValue getExtLoad(ISD::LoadExtType ExtType, const SDLoc &dl, EVT VT,
                      SDValue Chain, SDValue Ptr, EVT MemVT,
                      MachineMemOperand *MMO);
   SDValue getIndexedLoad(SDValue OrigLoad, const SDLoc &dl, SDValue Base,
                          SDValue Offset, ISD::MemIndexedMode AM);
   SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType, EVT VT,
                   const SDLoc &dl, SDValue Chain, SDValue Ptr, SDValue Offset,
                   MachinePointerInfo PtrInfo, EVT MemVT, Align Alignment,
                   MachineMemOperand::Flags MMOFlags = MachineMemOperand::MONone,
                   const AAMDNodes &AAInfo = AAMDNodes(),
                   const MDNode *Ranges = nullptr);
   inline SDValue getLoad(
       ISD::MemIndexedMode AM, ISD::LoadExtType ExtType, EVT VT, const SDLoc &dl,
       SDValue Chain, SDValue Ptr, SDValue Offset, MachinePointerInfo PtrInfo,
       EVT MemVT, MaybeAlign Alignment = MaybeAlign(),
       MachineMemOperand::Flags MMOFlags = MachineMemOperand::MONone,
       const AAMDNodes &AAInfo = AAMDNodes(), const MDNode *Ranges = nullptr) {
     // Ensures that codegen never sees a None Alignment.
     return getLoad(AM, ExtType, VT, dl, Chain, Ptr, Offset, PtrInfo, MemVT,
                    Alignment.value_or(getEVTAlign(MemVT)), MMOFlags, AAInfo,
                    Ranges);
   }
   SDValue getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType, EVT VT,
                   const SDLoc &dl, SDValue Chain, SDValue Ptr, SDValue Offset,
                   EVT MemVT, MachineMemOperand *MMO);
 
   /// Helper function to build ISD::STORE nodes.
   ///
   /// This function will set the MOStore flag on MMOFlags, but you can set it if
   /// you want.  The MOLoad and MOInvariant flags must not be set.
 
   SDValue
   getStore(SDValue Chain, const SDLoc &dl, SDValue Val, SDValue Ptr,
            MachinePointerInfo PtrInfo, Align Alignment,
            MachineMemOperand::Flags MMOFlags = MachineMemOperand::MONone,
            const AAMDNodes &AAInfo = AAMDNodes());
   inline SDValue
   getStore(SDValue Chain, const SDLoc &dl, SDValue Val, SDValue Ptr,
            MachinePointerInfo PtrInfo, MaybeAlign Alignment = MaybeAlign(),
            MachineMemOperand::Flags MMOFlags = MachineMemOperand::MONone,
            const AAMDNodes &AAInfo = AAMDNodes()) {
     return getStore(Chain, dl, Val, Ptr, PtrInfo,
                     Alignment.value_or(getEVTAlign(Val.getValueType())),
                     MMOFlags, AAInfo);
   }
   SDValue getStore(SDValue Chain, const SDLoc &dl, SDValue Val, SDValue Ptr,
                    MachineMemOperand *MMO);
   SDValue
   getTruncStore(SDValue Chain, const SDLoc &dl, SDValue Val, SDValue Ptr,
                 MachinePointerInfo PtrInfo, EVT SVT, Align Alignment,
                 MachineMemOperand::Flags MMOFlags = MachineMemOperand::MONone,
                 const AAMDNodes &AAInfo = AAMDNodes());
   inline SDValue
   getTruncStore(SDValue Chain, const SDLoc &dl, SDValue Val, SDValue Ptr,
                 MachinePointerInfo PtrInfo, EVT SVT,
                 MaybeAlign Alignment = MaybeAlign(),
                 MachineMemOperand::Flags MMOFlags = MachineMemOperand::MONone,
                 const AAMDNodes &AAInfo = AAMDNodes()) {
     return getTruncStore(Chain, dl, Val, Ptr, PtrInfo, SVT,
                          Alignment.value_or(getEVTAlign(SVT)), MMOFlags,
                          AAInfo);
   }
   SDValue getTruncStore(SDValue Chain, const SDLoc &dl, SDValue Val,
                         SDValue Ptr, EVT SVT, MachineMemOperand *MMO);
   SDValue getIndexedStore(SDValue OrigStore, const SDLoc &dl, SDValue Base,
                           SDValue Offset, ISD::MemIndexedMode AM);
 
   SDValue getLoadVP(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType, EVT VT,
                     const SDLoc &dl, SDValue Chain, SDValue Ptr, SDValue Offset,
                     SDValue Mask, SDValue EVL, MachinePointerInfo PtrInfo,
                     EVT MemVT, Align Alignment,
                     MachineMemOperand::Flags MMOFlags, const AAMDNodes &AAInfo,
                     const MDNode *Ranges = nullptr, bool IsExpanding = false);
   inline SDValue
   getLoadVP(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType, EVT VT,
             const SDLoc &dl, SDValue Chain, SDValue Ptr, SDValue Offset,
             SDValue Mask, SDValue EVL, MachinePointerInfo PtrInfo, EVT MemVT,
             MaybeAlign Alignment = MaybeAlign(),
             MachineMemOperand::Flags MMOFlags = MachineMemOperand::MONone,
             const AAMDNodes &AAInfo = AAMDNodes(),
             const MDNode *Ranges = nullptr, bool IsExpanding = false) {
     // Ensures that codegen never sees a None Alignment.
     return getLoadVP(AM, ExtType, VT, dl, Chain, Ptr, Offset, Mask, EVL,
                      PtrInfo, MemVT, Alignment.value_or(getEVTAlign(MemVT)),
                      MMOFlags, AAInfo, Ranges, IsExpanding);
   }
   SDValue getLoadVP(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType, EVT VT,
                     const SDLoc &dl, SDValue Chain, SDValue Ptr, SDValue Offset,
                     SDValue Mask, SDValue EVL, EVT MemVT,
                     MachineMemOperand *MMO, bool IsExpanding = false);
   SDValue getLoadVP(EVT VT, const SDLoc &dl, SDValue Chain, SDValue Ptr,
                     SDValue Mask, SDValue EVL, MachinePointerInfo PtrInfo,
                     MaybeAlign Alignment, MachineMemOperand::Flags MMOFlags,
                     const AAMDNodes &AAInfo, const MDNode *Ranges = nullptr,
                     bool IsExpanding = false);
   SDValue getLoadVP(EVT VT, const SDLoc &dl, SDValue Chain, SDValue Ptr,
                     SDValue Mask, SDValue EVL, MachineMemOperand *MMO,
                     bool IsExpanding = false);
   SDValue getExtLoadVP(ISD::LoadExtType ExtType, const SDLoc &dl, EVT VT,
                        SDValue Chain, SDValue Ptr, SDValue Mask, SDValue EVL,
                        MachinePointerInfo PtrInfo, EVT MemVT,
                        MaybeAlign Alignment, MachineMemOperand::Flags MMOFlags,
                        const AAMDNodes &AAInfo, bool IsExpanding = false);
   SDValue getExtLoadVP(ISD::LoadExtType ExtType, const SDLoc &dl, EVT VT,
                        SDValue Chain, SDValue Ptr, SDValue Mask, SDValue EVL,
                        EVT MemVT, MachineMemOperand *MMO,
                        bool IsExpanding = false);
   SDValue getIndexedLoadVP(SDValue OrigLoad, const SDLoc &dl, SDValue Base,
                            SDValue Offset, ISD::MemIndexedMode AM);
   SDValue getStoreVP(SDValue Chain, const SDLoc &dl, SDValue Val, SDValue Ptr,
                      SDValue Offset, SDValue Mask, SDValue EVL, EVT MemVT,
                      MachineMemOperand *MMO, ISD::MemIndexedMode AM,
                      bool IsTruncating = false, bool IsCompressing = false);
   SDValue getTruncStoreVP(SDValue Chain, const SDLoc &dl, SDValue Val,
                           SDValue Ptr, SDValue Mask, SDValue EVL,
                           MachinePointerInfo PtrInfo, EVT SVT, Align Alignment,
                           MachineMemOperand::Flags MMOFlags,
                           const AAMDNodes &AAInfo, bool IsCompressing = false);
   SDValue getTruncStoreVP(SDValue Chain, const SDLoc &dl, SDValue Val,
                           SDValue Ptr, SDValue Mask, SDValue EVL, EVT SVT,
                           MachineMemOperand *MMO, bool IsCompressing = false);
   SDValue getIndexedStoreVP(SDValue OrigStore, const SDLoc &dl, SDValue Base,
                             SDValue Offset, ISD::MemIndexedMode AM);
 
   SDValue getStridedLoadVP(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
                            EVT VT, const SDLoc &DL, SDValue Chain, SDValue Ptr,
                            SDValue Offset, SDValue Stride, SDValue Mask,
                            SDValue EVL, EVT MemVT, MachineMemOperand *MMO,
                            bool IsExpanding = false);
   SDValue getStridedLoadVP(EVT VT, const SDLoc &DL, SDValue Chain, SDValue Ptr,
                            SDValue Stride, SDValue Mask, SDValue EVL,
                            MachineMemOperand *MMO, bool IsExpanding = false);
   SDValue getExtStridedLoadVP(ISD::LoadExtType ExtType, const SDLoc &DL, EVT VT,
                               SDValue Chain, SDValue Ptr, SDValue Stride,
                               SDValue Mask, SDValue EVL, EVT MemVT,
                               MachineMemOperand *MMO, bool IsExpanding = false);
   SDValue getStridedStoreVP(SDValue Chain, const SDLoc &DL, SDValue Val,
                             SDValue Ptr, SDValue Offset, SDValue Stride,
                             SDValue Mask, SDValue EVL, EVT MemVT,
                             MachineMemOperand *MMO, ISD::MemIndexedMode AM,
                             bool IsTruncating = false,
                             bool IsCompressing = false);
   SDValue getTruncStridedStoreVP(SDValue Chain, const SDLoc &DL, SDValue Val,
                                  SDValue Ptr, SDValue Stride, SDValue Mask,
                                  SDValue EVL, EVT SVT, MachineMemOperand *MMO,
                                  bool IsCompressing = false);
 
   SDValue getGatherVP(SDVTList VTs, EVT VT, const SDLoc &dl,
                       ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
                       ISD::MemIndexType IndexType);
   SDValue getScatterVP(SDVTList VTs, EVT VT, const SDLoc &dl,
                        ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
                        ISD::MemIndexType IndexType);
 
   SDValue getMaskedLoad(EVT VT, const SDLoc &dl, SDValue Chain, SDValue Base,
                         SDValue Offset, SDValue Mask, SDValue Src0, EVT MemVT,
                         MachineMemOperand *MMO, ISD::MemIndexedMode AM,
                         ISD::LoadExtType, bool IsExpanding = false);
   SDValue getIndexedMaskedLoad(SDValue OrigLoad, const SDLoc &dl, SDValue Base,
                                SDValue Offset, ISD::MemIndexedMode AM);
   SDValue getMaskedStore(SDValue Chain, const SDLoc &dl, SDValue Val,
                          SDValue Base, SDValue Offset, SDValue Mask, EVT MemVT,
                          MachineMemOperand *MMO, ISD::MemIndexedMode AM,
                          bool IsTruncating = false, bool IsCompressing = false);
   SDValue getIndexedMaskedStore(SDValue OrigStore, const SDLoc &dl,
                                 SDValue Base, SDValue Offset,
                                 ISD::MemIndexedMode AM);
   SDValue getMaskedGather(SDVTList VTs, EVT MemVT, const SDLoc &dl,
                           ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
                           ISD::MemIndexType IndexType, ISD::LoadExtType ExtTy);
   SDValue getMaskedScatter(SDVTList VTs, EVT MemVT, const SDLoc &dl,
                            ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
                            ISD::MemIndexType IndexType,
                            bool IsTruncating = false);
   SDValue getMaskedHistogram(SDVTList VTs, EVT MemVT, const SDLoc &dl,
                              ArrayRef<SDValue> Ops, MachineMemOperand *MMO,
                              ISD::MemIndexType IndexType);
 
   SDValue getGetFPEnv(SDValue Chain, const SDLoc &dl, SDValue Ptr, EVT MemVT,
                       MachineMemOperand *MMO);
   SDValue getSetFPEnv(SDValue Chain, const SDLoc &dl, SDValue Ptr, EVT MemVT,
                       MachineMemOperand *MMO);
 
   /// Construct a node to track a Value* through the backend.
   SDValue getSrcValue(const Value *v);
 
   /// Return an MDNodeSDNode which holds an MDNode.
   SDValue getMDNode(const MDNode *MD);
 
   /// Return a bitcast using the SDLoc of the value operand, and casting to the
   /// provided type. Use getNode to set a custom SDLoc.
   SDValue getBitcast(EVT VT, SDValue V);
 
   /// Return an AddrSpaceCastSDNode.
   SDValue getAddrSpaceCast(const SDLoc &dl, EVT VT, SDValue Ptr, unsigned SrcAS,
                            unsigned DestAS);
 
   /// Return a freeze using the SDLoc of the value operand.
   SDValue getFreeze(SDValue V);
 
   /// Return an AssertAlignSDNode.
   SDValue getAssertAlign(const SDLoc &DL, SDValue V, Align A);
 
   /// Swap N1 and N2 if Opcode is a commutative binary opcode
   /// and the canonical form expects the opposite order.
   void canonicalizeCommutativeBinop(unsigned Opcode, SDValue &N1,
                                     SDValue &N2) const;
 
   /// Return the specified value casted to
   /// the target's desired shift amount type.
   SDValue getShiftAmountOperand(EVT LHSTy, SDValue Op);
 
   /// Create the DAG equivalent of vector_partial_reduce where Op1 and Op2 are
   /// its operands and ReducedTY is the intrinsic's return type.
   SDValue getPartialReduceAdd(SDLoc DL, EVT ReducedTy, SDValue Op1,
                               SDValue Op2);
 
   /// Expands a node with multiple results to an FP or vector libcall. The
   /// libcall is expected to take all the operands of the \p Node followed by
   /// output pointers for each of the results. \p CallRetResNo can be optionally
   /// set to indicate that one of the results comes from the libcall's return
   /// value.
   bool expandMultipleResultFPLibCall(RTLIB::Libcall LC, SDNode *Node,
                                      SmallVectorImpl<SDValue> &Results,
                                      std::optional<unsigned> CallRetResNo = {});
 
   /// Expand the specified \c ISD::VAARG node as the Legalize pass would.
   SDValue expandVAArg(SDNode *Node);
 
   /// Expand the specified \c ISD::VACOPY node as the Legalize pass would.
   SDValue expandVACopy(SDNode *Node);
 
   /// Return a GlobalAddress of the function from the current module with
   /// name matching the given ExternalSymbol. Additionally can provide the
   /// matched function.
   /// Panic if the function doesn't exist.
   SDValue getSymbolFunctionGlobalAddress(SDValue Op,
                                          Function **TargetFunction = nullptr);
 
   /// *Mutate* the specified node in-place to have the
   /// specified operands.  If the resultant node already exists in the DAG,
   /// this does not modify the specified node, instead it returns the node that
   /// already exists.  If the resultant node does not exist in the DAG, the
   /// input node is returned.  As a degenerate case, if you specify the same
   /// input operands as the node already has, the input node is returned.
   SDNode *UpdateNodeOperands(SDNode *N, SDValue Op);
   SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2);
   SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
                                SDValue Op3);
   SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
                                SDValue Op3, SDValue Op4);
   SDNode *UpdateNodeOperands(SDNode *N, SDValue Op1, SDValue Op2,
                                SDValue Op3, SDValue Op4, SDValue Op5);
   SDNode *UpdateNodeOperands(SDNode *N, ArrayRef<SDValue> Ops);
 
   /// Creates a new TokenFactor containing \p Vals. If \p Vals contains 64k
   /// values or more, move values into new TokenFactors in 64k-1 blocks, until
   /// the final TokenFactor has less than 64k operands.
   SDValue getTokenFactor(const SDLoc &DL, SmallVectorImpl<SDValue> &Vals);
 
   /// *Mutate* the specified machine node's memory references to the provided
   /// list.
   void setNodeMemRefs(MachineSDNode *N,
                       ArrayRef<MachineMemOperand *> NewMemRefs);
 
   // Calculate divergence of node \p N based on its operands.
   bool calculateDivergence(SDNode *N);
 
   // Propagates the change in divergence to users
   void updateDivergence(SDNode * N);
 
   /// These are used for target selectors to *mutate* the
   /// specified node to have the specified return type, Target opcode, and
   /// operands.  Note that target opcodes are stored as
   /// ~TargetOpcode in the node opcode field.  The resultant node is returned.
   SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT);
   SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT, SDValue Op1);
   SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT,
                        SDValue Op1, SDValue Op2);
   SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT,
                        SDValue Op1, SDValue Op2, SDValue Op3);
   SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT,
                        ArrayRef<SDValue> Ops);
   SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT1, EVT VT2);
   SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT1,
                        EVT VT2, ArrayRef<SDValue> Ops);
   SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT1,
                        EVT VT2, EVT VT3, ArrayRef<SDValue> Ops);
   SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, EVT VT1,
                        EVT VT2, SDValue Op1, SDValue Op2);
   SDNode *SelectNodeTo(SDNode *N, unsigned MachineOpc, SDVTList VTs,
                        ArrayRef<SDValue> Ops);
 
   /// This *mutates* the specified node to have the specified
   /// return type, opcode, and operands.
   SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
                       ArrayRef<SDValue> Ops);
 
   /// Mutate the specified strict FP node to its non-strict equivalent,
   /// unlinking the node from its chain and dropping the metadata arguments.
   /// The node must be a strict FP node.
   SDNode *mutateStrictFPToFP(SDNode *Node);
 
   /// These are used for target selectors to create a new node
   /// with specified return type(s), MachineInstr opcode, and operands.
   ///
   /// Note that getMachineNode returns the resultant node.  If there is already
   /// a node of the specified opcode and operands, it returns that node instead
   /// of the current one.
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl, EVT VT);
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl, EVT VT,
                                 SDValue Op1);
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl, EVT VT,
                                 SDValue Op1, SDValue Op2);
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl, EVT VT,
                                 SDValue Op1, SDValue Op2, SDValue Op3);
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl, EVT VT,
                                 ArrayRef<SDValue> Ops);
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl, EVT VT1,
                                 EVT VT2, SDValue Op1, SDValue Op2);
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl, EVT VT1,
                                 EVT VT2, SDValue Op1, SDValue Op2, SDValue Op3);
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl, EVT VT1,
                                 EVT VT2, ArrayRef<SDValue> Ops);
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl, EVT VT1,
                                 EVT VT2, EVT VT3, SDValue Op1, SDValue Op2);
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl, EVT VT1,
                                 EVT VT2, EVT VT3, SDValue Op1, SDValue Op2,
                                 SDValue Op3);
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl, EVT VT1,
                                 EVT VT2, EVT VT3, ArrayRef<SDValue> Ops);
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl,
                                 ArrayRef<EVT> ResultTys, ArrayRef<SDValue> Ops);
   MachineSDNode *getMachineNode(unsigned Opcode, const SDLoc &dl, SDVTList VTs,
                                 ArrayRef<SDValue> Ops);
 
   /// A convenience function for creating TargetInstrInfo::EXTRACT_SUBREG nodes.
   SDValue getTargetExtractSubreg(int SRIdx, const SDLoc &DL, EVT VT,
                                  SDValue Operand);
 
   /// A convenience function for creating TargetInstrInfo::INSERT_SUBREG nodes.
   SDValue getTargetInsertSubreg(int SRIdx, const SDLoc &DL, EVT VT,
                                 SDValue Operand, SDValue Subreg);
 
   /// Get the specified node if it's already available, or else return NULL.
   SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTList,
                           ArrayRef<SDValue> Ops, const SDNodeFlags Flags);
   SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTList,
                           ArrayRef<SDValue> Ops);
 
   /// Check if a node exists without modifying its flags.
   bool doesNodeExist(unsigned Opcode, SDVTList VTList, ArrayRef<SDValue> Ops);
 
   /// Creates a SDDbgValue node.
   SDDbgValue *getDbgValue(DIVariable *Var, DIExpression *Expr, SDNode *N,
                           unsigned R, bool IsIndirect, const DebugLoc &DL,
                           unsigned O);
 
   /// Creates a constant SDDbgValue node.
   SDDbgValue *getConstantDbgValue(DIVariable *Var, DIExpression *Expr,
                                   const Value *C, const DebugLoc &DL,
                                   unsigned O);
 
   /// Creates a FrameIndex SDDbgValue node.
   SDDbgValue *getFrameIndexDbgValue(DIVariable *Var, DIExpression *Expr,
                                     unsigned FI, bool IsIndirect,
                                     const DebugLoc &DL, unsigned O);
 
   /// Creates a FrameIndex SDDbgValue node.
   SDDbgValue *getFrameIndexDbgValue(DIVariable *Var, DIExpression *Expr,
                                     unsigned FI,
                                     ArrayRef<SDNode *> Dependencies,
                                     bool IsIndirect, const DebugLoc &DL,
                                     unsigned O);
 
   /// Creates a VReg SDDbgValue node.
   SDDbgValue *getVRegDbgValue(DIVariable *Var, DIExpression *Expr,
                               unsigned VReg, bool IsIndirect,
                               const DebugLoc &DL, unsigned O);
 
   /// Creates a SDDbgValue node from a list of locations.
   SDDbgValue *getDbgValueList(DIVariable *Var, DIExpression *Expr,
                               ArrayRef<SDDbgOperand> Locs,
                               ArrayRef<SDNode *> Dependencies, bool IsIndirect,
                               const DebugLoc &DL, unsigned O, bool IsVariadic);
 
   /// Creates a SDDbgLabel node.
   SDDbgLabel *getDbgLabel(DILabel *Label, const DebugLoc &DL, unsigned O);
 
   /// Transfer debug values from one node to another, while optionally
   /// generating fragment expressions for split-up values. If \p InvalidateDbg
   /// is set, debug values are invalidated after they are transferred.
   void transferDbgValues(SDValue From, SDValue To, unsigned OffsetInBits = 0,
                          unsigned SizeInBits = 0, bool InvalidateDbg = true);
 
   /// Remove the specified node from the system. If any of its
   /// operands then becomes dead, remove them as well. Inform UpdateListener
   /// for each node deleted.
   void RemoveDeadNode(SDNode *N);
 
   /// This method deletes the unreachable nodes in the
   /// given list, and any nodes that become unreachable as a result.
   void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes);
 
   /// Modify anything using 'From' to use 'To' instead.
   /// This can cause recursive merging of nodes in the DAG.  Use the first
   /// version if 'From' is known to have a single result, use the second
   /// if you have two nodes with identical results (or if 'To' has a superset
   /// of the results of 'From'), use the third otherwise.
   ///
   /// These methods all take an optional UpdateListener, which (if not null) is
   /// informed about nodes that are deleted and modified due to recursive
   /// changes in the dag.
   ///
   /// These functions only replace all existing uses. It's possible that as
   /// these replacements are being performed, CSE may cause the From node
   /// to be given new uses. These new uses of From are left in place, and
   /// not automatically transferred to To.
   ///
   void ReplaceAllUsesWith(SDValue From, SDValue To);
   void ReplaceAllUsesWith(SDNode *From, SDNode *To);
   void ReplaceAllUsesWith(SDNode *From, const SDValue *To);
 
   /// Replace any uses of From with To, leaving
   /// uses of other values produced by From.getNode() alone.
   void ReplaceAllUsesOfValueWith(SDValue From, SDValue To);
 
   /// Like ReplaceAllUsesOfValueWith, but for multiple values at once.
   /// This correctly handles the case where
   /// there is an overlap between the From values and the To values.
   void ReplaceAllUsesOfValuesWith(const SDValue *From, const SDValue *To,
                                   unsigned Num);
 
   /// If an existing load has uses of its chain, create a token factor node with
   /// that chain and the new memory node's chain and update users of the old
   /// chain to the token factor. This ensures that the new memory node will have
   /// the same relative memory dependency position as the old load. Returns the
   /// new merged load chain.
   SDValue makeEquivalentMemoryOrdering(SDValue OldChain, SDValue NewMemOpChain);
 
   /// If an existing load has uses of its chain, create a token factor node with
   /// that chain and the new memory node's chain and update users of the old
   /// chain to the token factor. This ensures that the new memory node will have
   /// the same relative memory dependency position as the old load. Returns the
   /// new merged load chain.
   SDValue makeEquivalentMemoryOrdering(LoadSDNode *OldLoad, SDValue NewMemOp);
 
   /// Topological-sort the AllNodes list and a
   /// assign a unique node id for each node in the DAG based on their
   /// topological order. Returns the number of nodes.
   unsigned AssignTopologicalOrder();
 
   /// Move node N in the AllNodes list to be immediately
   /// before the given iterator Position. This may be used to update the
   /// topological ordering when the list of nodes is modified.
   void RepositionNode(allnodes_iterator Position, SDNode *N) {
     AllNodes.insert(Position, AllNodes.remove(N));
   }
 
   /// Add a dbg_value SDNode. If SD is non-null that means the
   /// value is produced by SD.
   void AddDbgValue(SDDbgValue *DB, bool isParameter);
 
   /// Add a dbg_label SDNode.
   void AddDbgLabel(SDDbgLabel *DB);
 
   /// Get the debug values which reference the given SDNode.
   ArrayRef<SDDbgValue*> GetDbgValues(const SDNode* SD) const {
     return DbgInfo->getSDDbgValues(SD);
   }
 
 public:
   /// Return true if there are any SDDbgValue nodes associated
   /// with this SelectionDAG.
   bool hasDebugValues() const { return !DbgInfo->empty(); }
 
   SDDbgInfo::DbgIterator DbgBegin() const { return DbgInfo->DbgBegin(); }
   SDDbgInfo::DbgIterator DbgEnd() const  { return DbgInfo->DbgEnd(); }
 
   SDDbgInfo::DbgIterator ByvalParmDbgBegin() const {
     return DbgInfo->ByvalParmDbgBegin();
   }
   SDDbgInfo::DbgIterator ByvalParmDbgEnd() const {
     return DbgInfo->ByvalParmDbgEnd();
   }
 
   SDDbgInfo::DbgLabelIterator DbgLabelBegin() const {
     return DbgInfo->DbgLabelBegin();
   }
   SDDbgInfo::DbgLabelIterator DbgLabelEnd() const {
     return DbgInfo->DbgLabelEnd();
   }
 
   /// To be invoked on an SDNode that is slated to be erased. This
   /// function mirrors \c llvm::salvageDebugInfo.
   void salvageDebugInfo(SDNode &N);
 
   void dump() const;
 
   /// In most cases this function returns the ABI alignment for a given type,
   /// except for illegal vector types where the alignment exceeds that of the
   /// stack. In such cases we attempt to break the vector down to a legal type
   /// and return the ABI alignment for that instead.
   Align getReducedAlign(EVT VT, bool UseABI);
 
   /// Create a stack temporary based on the size in bytes and the alignment
   SDValue CreateStackTemporary(TypeSize Bytes, Align Alignment);
 
   /// Create a stack temporary, suitable for holding the specified value type.
   /// If minAlign is specified, the slot size will have at least that alignment.
   SDValue CreateStackTemporary(EVT VT, unsigned minAlign = 1);
 
   /// Create a stack temporary suitable for holding either of the specified
   /// value types.
   SDValue CreateStackTemporary(EVT VT1, EVT VT2);
 
   SDValue FoldSymbolOffset(unsigned Opcode, EVT VT,
                            const GlobalAddressSDNode *GA,
                            const SDNode *N2);
 
   SDValue FoldConstantArithmetic(unsigned Opcode, const SDLoc &DL, EVT VT,
                                  ArrayRef<SDValue> Ops,
                                  SDNodeFlags Flags = SDNodeFlags());
 
   /// Fold floating-point operations when all operands are constants and/or
   /// undefined.
   SDValue foldConstantFPMath(unsigned Opcode, const SDLoc &DL, EVT VT,
                              ArrayRef<SDValue> Ops);
 
   /// Constant fold a setcc to true or false.
   SDValue FoldSetCC(EVT VT, SDValue N1, SDValue N2, ISD::CondCode Cond,
                     const SDLoc &dl);
 
   /// Return true if the sign bit of Op is known to be zero.
   /// We use this predicate to simplify operations downstream.
   bool SignBitIsZero(SDValue Op, unsigned Depth = 0) const;
 
   /// Return true if 'Op & Mask' is known to be zero.  We
   /// use this predicate to simplify operations downstream.  Op and Mask are
   /// known to be the same type.
   bool MaskedValueIsZero(SDValue Op, const APInt &Mask,
                          unsigned Depth = 0) const;
 
   /// Return true if 'Op & Mask' is known to be zero in DemandedElts.  We
   /// use this predicate to simplify operations downstream.  Op and Mask are
   /// known to be the same type.
   bool MaskedValueIsZero(SDValue Op, const APInt &Mask,
                          const APInt &DemandedElts, unsigned Depth = 0) const;
 
   /// Return true if 'Op' is known to be zero in DemandedElts.  We
   /// use this predicate to simplify operations downstream.
   bool MaskedVectorIsZero(SDValue Op, const APInt &DemandedElts,
                           unsigned Depth = 0) const;
 
   /// Return true if '(Op & Mask) == Mask'.
   /// Op and Mask are known to be the same type.
   bool MaskedValueIsAllOnes(SDValue Op, const APInt &Mask,
                             unsigned Depth = 0) const;
 
   /// For each demanded element of a vector, see if it is known to be zero.
   APInt computeVectorKnownZeroElements(SDValue Op, const APInt &DemandedElts,
                                        unsigned Depth = 0) const;
 
   /// Determine which bits of Op are known to be either zero or one and return
   /// them in Known. For vectors, the known bits are those that are shared by
   /// every vector element.
   /// Targets can implement the computeKnownBitsForTargetNode method in the
   /// TargetLowering class to allow target nodes to be understood.
   KnownBits computeKnownBits(SDValue Op, unsigned Depth = 0) const;
 
   /// Determine which bits of Op are known to be either zero or one and return
   /// them in Known. The DemandedElts argument allows us to only collect the
   /// known bits that are shared by the requested vector elements.
   /// Targets can implement the computeKnownBitsForTargetNode method in the
   /// TargetLowering class to allow target nodes to be understood.
   KnownBits computeKnownBits(SDValue Op, const APInt &DemandedElts,
                              unsigned Depth = 0) const;
 
   /// Used to represent the possible overflow behavior of an operation.
   /// Never: the operation cannot overflow.
   /// Always: the operation will always overflow.
   /// Sometime: the operation may or may not overflow.
   enum OverflowKind {
     OFK_Never,
     OFK_Sometime,
     OFK_Always,
   };
 
   /// Determine if the result of the signed addition of 2 nodes can overflow.
   OverflowKind computeOverflowForSignedAdd(SDValue N0, SDValue N1) const;
 
   /// Determine if the result of the unsigned addition of 2 nodes can overflow.
   OverflowKind computeOverflowForUnsignedAdd(SDValue N0, SDValue N1) const;
 
   /// Determine if the result of the addition of 2 nodes can overflow.
   OverflowKind computeOverflowForAdd(bool IsSigned, SDValue N0,
                                      SDValue N1) const {
     return IsSigned ? computeOverflowForSignedAdd(N0, N1)
                     : computeOverflowForUnsignedAdd(N0, N1);
   }
 
   /// Determine if the result of the addition of 2 nodes can never overflow.
   bool willNotOverflowAdd(bool IsSigned, SDValue N0, SDValue N1) const {
     return computeOverflowForAdd(IsSigned, N0, N1) == OFK_Never;
   }
 
   /// Determine if the result of the signed sub of 2 nodes can overflow.
   OverflowKind computeOverflowForSignedSub(SDValue N0, SDValue N1) const;
 
   /// Determine if the result of the unsigned sub of 2 nodes can overflow.
   OverflowKind computeOverflowForUnsignedSub(SDValue N0, SDValue N1) const;
 
   /// Determine if the result of the sub of 2 nodes can overflow.
   OverflowKind computeOverflowForSub(bool IsSigned, SDValue N0,
                                      SDValue N1) const {
     return IsSigned ? computeOverflowForSignedSub(N0, N1)
                     : computeOverflowForUnsignedSub(N0, N1);
   }
 
   /// Determine if the result of the sub of 2 nodes can never overflow.
   bool willNotOverflowSub(bool IsSigned, SDValue N0, SDValue N1) const {
     return computeOverflowForSub(IsSigned, N0, N1) == OFK_Never;
   }
 
   /// Determine if the result of the signed mul of 2 nodes can overflow.
   OverflowKind computeOverflowForSignedMul(SDValue N0, SDValue N1) const;
 
   /// Determine if the result of the unsigned mul of 2 nodes can overflow.
   OverflowKind computeOverflowForUnsignedMul(SDValue N0, SDValue N1) const;
 
   /// Determine if the result of the mul of 2 nodes can overflow.
   OverflowKind computeOverflowForMul(bool IsSigned, SDValue N0,
                                      SDValue N1) const {
     return IsSigned ? computeOverflowForSignedMul(N0, N1)
                     : computeOverflowForUnsignedMul(N0, N1);
   }
 
   /// Determine if the result of the mul of 2 nodes can never overflow.
   bool willNotOverflowMul(bool IsSigned, SDValue N0, SDValue N1) const {
     return computeOverflowForMul(IsSigned, N0, N1) == OFK_Never;
   }
 
   /// Test if the given value is known to have exactly one bit set. This differs
   /// from computeKnownBits in that it doesn't necessarily determine which bit
   /// is set.
   bool isKnownToBeAPowerOfTwo(SDValue Val, unsigned Depth = 0) const;
 
   /// Test if the given _fp_ value is known to be an integer power-of-2, either
   /// positive or negative.
   bool isKnownToBeAPowerOfTwoFP(SDValue Val, unsigned Depth = 0) const;
 
   /// Return the number of times the sign bit of the register is replicated into
   /// the other bits. We know that at least 1 bit is always equal to the sign
   /// bit (itself), but other cases can give us information. For example,
   /// immediately after an "SRA X, 2", we know that the top 3 bits are all equal
   /// to each other, so we return 3. Targets can implement the
   /// ComputeNumSignBitsForTarget method in the TargetLowering class to allow
   /// target nodes to be understood.
   unsigned ComputeNumSignBits(SDValue Op, unsigned Depth = 0) const;
 
   /// Return the number of times the sign bit of the register is replicated into
   /// the other bits. We know that at least 1 bit is always equal to the sign
   /// bit (itself), but other cases can give us information. For example,
   /// immediately after an "SRA X, 2", we know that the top 3 bits are all equal
   /// to each other, so we return 3. The DemandedElts argument allows
   /// us to only collect the minimum sign bits of the requested vector elements.
   /// Targets can implement the ComputeNumSignBitsForTarget method in the
   /// TargetLowering class to allow target nodes to be understood.
   unsigned ComputeNumSignBits(SDValue Op, const APInt &DemandedElts,
                               unsigned Depth = 0) const;
 
   /// Get the upper bound on bit size for this Value \p Op as a signed integer.
   /// i.e.  x == sext(trunc(x to MaxSignedBits) to bitwidth(x)).
   /// Similar to the APInt::getSignificantBits function.
   /// Helper wrapper to ComputeNumSignBits.
   unsigned ComputeMaxSignificantBits(SDValue Op, unsigned Depth = 0) const;
 
   /// Get the upper bound on bit size for this Value \p Op as a signed integer.
   /// i.e.  x == sext(trunc(x to MaxSignedBits) to bitwidth(x)).
   /// Similar to the APInt::getSignificantBits function.
   /// Helper wrapper to ComputeNumSignBits.
   unsigned ComputeMaxSignificantBits(SDValue Op, const APInt &DemandedElts,
                                      unsigned Depth = 0) const;
 
   /// Return true if this function can prove that \p Op is never poison
   /// and, if \p PoisonOnly is false, does not have undef bits.
   bool isGuaranteedNotToBeUndefOrPoison(SDValue Op, bool PoisonOnly = false,
                                         unsigned Depth = 0) const;
 
   /// Return true if this function can prove that \p Op is never poison
   /// and, if \p PoisonOnly is false, does not have undef bits. The DemandedElts
   /// argument limits the check to the requested vector elements.
   bool isGuaranteedNotToBeUndefOrPoison(SDValue Op, const APInt &DemandedElts,
                                         bool PoisonOnly = false,
                                         unsigned Depth = 0) const;
 
   /// Return true if this function can prove that \p Op is never poison.
   bool isGuaranteedNotToBePoison(SDValue Op, unsigned Depth = 0) const {
     return isGuaranteedNotToBeUndefOrPoison(Op, /*PoisonOnly*/ true, Depth);
   }
 
   /// Return true if this function can prove that \p Op is never poison. The
   /// DemandedElts argument limits the check to the requested vector elements.
   bool isGuaranteedNotToBePoison(SDValue Op, const APInt &DemandedElts,
                                  unsigned Depth = 0) const {
     return isGuaranteedNotToBeUndefOrPoison(Op, DemandedElts,
                                             /*PoisonOnly*/ true, Depth);
   }
 
   /// Return true if Op can create undef or poison from non-undef & non-poison
   /// operands. The DemandedElts argument limits the check to the requested
   /// vector elements.
   ///
   /// \p ConsiderFlags controls whether poison producing flags on the
   /// instruction are considered.  This can be used to see if the instruction
   /// could still introduce undef or poison even without poison generating flags
   /// which might be on the instruction.  (i.e. could the result of
   /// Op->dropPoisonGeneratingFlags() still create poison or undef)
   bool canCreateUndefOrPoison(SDValue Op, const APInt &DemandedElts,
                               bool PoisonOnly = false,
                               bool ConsiderFlags = true,
                               unsigned Depth = 0) const;
 
   /// Return true if Op can create undef or poison from non-undef & non-poison
   /// operands.
   ///
   /// \p ConsiderFlags controls whether poison producing flags on the
   /// instruction are considered.  This can be used to see if the instruction
   /// could still introduce undef or poison even without poison generating flags
   /// which might be on the instruction.  (i.e. could the result of
   /// Op->dropPoisonGeneratingFlags() still create poison or undef)
   bool canCreateUndefOrPoison(SDValue Op, bool PoisonOnly = false,
                               bool ConsiderFlags = true,
                               unsigned Depth = 0) const;
 
   /// Return true if the specified operand is an ISD::OR or ISD::XOR node
   /// that can be treated as an ISD::ADD node.
   /// or(x,y) == add(x,y) iff haveNoCommonBitsSet(x,y)
   /// xor(x,y) == add(x,y) iff isMinSignedConstant(y) && !NoWrap
   /// If \p NoWrap is true, this will not match ISD::XOR.
   bool isADDLike(SDValue Op, bool NoWrap = false) const;
 
   /// Return true if the specified operand is an ISD::ADD with a ConstantSDNode
   /// on the right-hand side, or if it is an ISD::OR with a ConstantSDNode that
   /// is guaranteed to have the same semantics as an ADD. This handles the
   /// equivalence:
   ///     X|Cst == X+Cst iff X&Cst = 0.
   bool isBaseWithConstantOffset(SDValue Op) const;
 
   /// Test whether the given SDValue (or all elements of it, if it is a
   /// vector) is known to never be NaN. If \p SNaN is true, returns if \p Op is
   /// known to never be a signaling NaN (it may still be a qNaN).
   bool isKnownNeverNaN(SDValue Op, bool SNaN = false, unsigned Depth = 0) const;
 
   /// \returns true if \p Op is known to never be a signaling NaN.
   bool isKnownNeverSNaN(SDValue Op, unsigned Depth = 0) const {
     return isKnownNeverNaN(Op, true, Depth);
   }
 
   /// Test whether the given floating point SDValue is known to never be
   /// positive or negative zero.
   bool isKnownNeverZeroFloat(SDValue Op) const;
 
   /// Test whether the given SDValue is known to contain non-zero value(s).
   bool isKnownNeverZero(SDValue Op, unsigned Depth = 0) const;
 
   /// Test whether the given float value is known to be positive. +0.0, +inf and
   /// +nan are considered positive, -0.0, -inf and -nan are not.
   bool cannotBeOrderedNegativeFP(SDValue Op) const;
 
   /// Test whether two SDValues are known to compare equal. This
   /// is true if they are the same value, or if one is negative zero and the
   /// other positive zero.
   bool isEqualTo(SDValue A, SDValue B) const;
 
   /// Return true if A and B have no common bits set. As an example, this can
   /// allow an 'add' to be transformed into an 'or'.
   bool haveNoCommonBitsSet(SDValue A, SDValue B) const;
 
   /// Test whether \p V has a splatted value for all the demanded elements.
   ///
   /// On success \p UndefElts will indicate the elements that have UNDEF
   /// values instead of the splat value, this is only guaranteed to be correct
   /// for \p DemandedElts.
   ///
   /// NOTE: The function will return true for a demanded splat of UNDEF values.
   bool isSplatValue(SDValue V, const APInt &DemandedElts, APInt &UndefElts,
                     unsigned Depth = 0) const;
 
   /// Test whether \p V has a splatted value.
   bool isSplatValue(SDValue V, bool AllowUndefs = false) const;
 
   /// If V is a splatted value, return the source vector and its splat index.
   SDValue getSplatSourceVector(SDValue V, int &SplatIndex);
 
   /// If V is a splat vector, return its scalar source operand by extracting
   /// that element from the source vector. If LegalTypes is true, this method
   /// may only return a legally-typed splat value. If it cannot legalize the
   /// splatted value it will return SDValue().
   SDValue getSplatValue(SDValue V, bool LegalTypes = false);
 
   /// If a SHL/SRA/SRL node \p V has shift amounts that are all less than the
   /// element bit-width of the shift node, return the valid constant range.
   std::optional<ConstantRange>
   getValidShiftAmountRange(SDValue V, const APInt &DemandedElts,
                            unsigned Depth) const;
 
   /// If a SHL/SRA/SRL node \p V has a uniform shift amount
   /// that is less than the element bit-width of the shift node, return it.
   std::optional<uint64_t> getValidShiftAmount(SDValue V,
                                               const APInt &DemandedElts,
                                               unsigned Depth = 0) const;
 
   /// If a SHL/SRA/SRL node \p V has a uniform shift amount
   /// that is less than the element bit-width of the shift node, return it.
   std::optional<uint64_t> getValidShiftAmount(SDValue V,
                                               unsigned Depth = 0) const;
 
   /// If a SHL/SRA/SRL node \p V has shift amounts that are all less than the
   /// element bit-width of the shift node, return the minimum possible value.
   std::optional<uint64_t> getValidMinimumShiftAmount(SDValue V,
                                                      const APInt &DemandedElts,
                                                      unsigned Depth = 0) const;
 
   /// If a SHL/SRA/SRL node \p V has shift amounts that are all less than the
   /// element bit-width of the shift node, return the minimum possible value.
   std::optional<uint64_t> getValidMinimumShiftAmount(SDValue V,
                                                      unsigned Depth = 0) const;
 
   /// If a SHL/SRA/SRL node \p V has shift amounts that are all less than the
   /// element bit-width of the shift node, return the maximum possible value.
   std::optional<uint64_t> getValidMaximumShiftAmount(SDValue V,
                                                      const APInt &DemandedElts,
                                                      unsigned Depth = 0) const;
 
   /// If a SHL/SRA/SRL node \p V has shift amounts that are all less than the
   /// element bit-width of the shift node, return the maximum possible value.
   std::optional<uint64_t> getValidMaximumShiftAmount(SDValue V,
                                                      unsigned Depth = 0) const;
 
   /// Match a binop + shuffle pyramid that represents a horizontal reduction
   /// over the elements of a vector starting from the EXTRACT_VECTOR_ELT node /p
   /// Extract. The reduction must use one of the opcodes listed in /p
   /// CandidateBinOps and on success /p BinOp will contain the matching opcode.
   /// Returns the vector that is being reduced on, or SDValue() if a reduction
   /// was not matched. If \p AllowPartials is set then in the case of a
   /// reduction pattern that only matches the first few stages, the extracted
   /// subvector of the start of the reduction is returned.
   SDValue matchBinOpReduction(SDNode *Extract, ISD::NodeType &BinOp,
                               ArrayRef<ISD::NodeType> CandidateBinOps,
                               bool AllowPartials = false);
 
   /// Utility function used by legalize and lowering to
   /// "unroll" a vector operation by splitting out the scalars and operating
   /// on each element individually.  If the ResNE is 0, fully unroll the vector
   /// op. If ResNE is less than the width of the vector op, unroll up to ResNE.
   /// If the  ResNE is greater than the width of the vector op, unroll the
   /// vector op and fill the end of the resulting vector with UNDEFS.
   SDValue UnrollVectorOp(SDNode *N, unsigned ResNE = 0);
 
   /// Like UnrollVectorOp(), but for the [US](ADD|SUB|MUL)O family of opcodes.
   /// This is a separate function because those opcodes have two results.
   std::pair<SDValue, SDValue> UnrollVectorOverflowOp(SDNode *N,
                                                      unsigned ResNE = 0);
 
   /// Return true if loads are next to each other and can be
   /// merged. Check that both are nonvolatile and if LD is loading
   /// 'Bytes' bytes from a location that is 'Dist' units away from the
   /// location that the 'Base' load is loading from.
   bool areNonVolatileConsecutiveLoads(LoadSDNode *LD, LoadSDNode *Base,
                                       unsigned Bytes, int Dist) const;
 
   /// Infer alignment of a load / store address. Return std::nullopt if it
   /// cannot be inferred.
   MaybeAlign InferPtrAlign(SDValue Ptr) const;
 
   /// Split the scalar node with EXTRACT_ELEMENT using the provided VTs and
   /// return the low/high part.
   std::pair<SDValue, SDValue> SplitScalar(const SDValue &N, const SDLoc &DL,
                                           const EVT &LoVT, const EVT &HiVT);
 
   /// Compute the VTs needed for the low/hi parts of a type
   /// which is split (or expanded) into two not necessarily identical pieces.
   std::pair<EVT, EVT> GetSplitDestVTs(const EVT &VT) const;
 
   /// Compute the VTs needed for the low/hi parts of a type, dependent on an
   /// enveloping VT that has been split into two identical pieces. Sets the
   /// HisIsEmpty flag when hi type has zero storage size.
   std::pair<EVT, EVT> GetDependentSplitDestVTs(const EVT &VT, const EVT &EnvVT,
                                                bool *HiIsEmpty) const;
 
   /// Split the vector with EXTRACT_SUBVECTOR using the provided
   /// VTs and return the low/high part.
   std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL,
                                           const EVT &LoVT, const EVT &HiVT);
 
   /// Split the vector with EXTRACT_SUBVECTOR and return the low/high part.
   std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL) {
     EVT LoVT, HiVT;
     std::tie(LoVT, HiVT) = GetSplitDestVTs(N.getValueType());
     return SplitVector(N, DL, LoVT, HiVT);
   }
 
   /// Split the explicit vector length parameter of a VP operation.
   std::pair<SDValue, SDValue> SplitEVL(SDValue N, EVT VecVT, const SDLoc &DL);
 
   /// Split the node's operand with EXTRACT_SUBVECTOR and
   /// return the low/high part.
   std::pair<SDValue, SDValue> SplitVectorOperand(const SDNode *N, unsigned OpNo)
   {
     return SplitVector(N->getOperand(OpNo), SDLoc(N));
   }
 
   /// Widen the vector up to the next power of two using INSERT_SUBVECTOR.
   SDValue WidenVector(const SDValue &N, const SDLoc &DL);
 
   /// Append the extracted elements from Start to Count out of the vector Op in
   /// Args. If Count is 0, all of the elements will be extracted. The extracted
   /// elements will have type EVT if it is provided, and otherwise their type
   /// will be Op's element type.
   void ExtractVectorElements(SDValue Op, SmallVectorImpl<SDValue> &Args,
                              unsigned Start = 0, unsigned Count = 0,
                              EVT EltVT = EVT());
 
   /// Compute the default alignment value for the given type.
   Align getEVTAlign(EVT MemoryVT) const;
 
   /// Test whether the given value is a constant int or similar node.
   bool isConstantIntBuildVectorOrConstantInt(SDValue N,
                                              bool AllowOpaques = true) const;
 
   /// Test whether the given value is a constant FP or similar node.
   bool isConstantFPBuildVectorOrConstantFP(SDValue N) const;
 
   /// \returns true if \p N is any kind of constant or build_vector of
   /// constants, int or float. If a vector, it may not necessarily be a splat.
   inline bool isConstantValueOfAnyType(SDValue N) const {
     return isConstantIntBuildVectorOrConstantInt(N) ||
            isConstantFPBuildVectorOrConstantFP(N);
   }
 
   /// Check if a value \op N is a constant using the target's BooleanContent for
   /// its type.
   std::optional<bool> isBoolConstant(SDValue N,
                                      bool AllowTruncation = false) const;
 
   /// Set CallSiteInfo to be associated with Node.
   void addCallSiteInfo(const SDNode *Node, CallSiteInfo &&CallInfo) {
     SDEI[Node].CSInfo = std::move(CallInfo);
   }
   /// Return CallSiteInfo associated with Node, or a default if none exists.
   CallSiteInfo getCallSiteInfo(const SDNode *Node) {
     auto I = SDEI.find(Node);
     return I != SDEI.end() ? std::move(I->second).CSInfo : CallSiteInfo();
   }
   /// Set HeapAllocSite to be associated with Node.
   void addHeapAllocSite(const SDNode *Node, MDNode *MD) {
     SDEI[Node].HeapAllocSite = MD;
   }
   /// Return HeapAllocSite associated with Node, or nullptr if none exists.
   MDNode *getHeapAllocSite(const SDNode *Node) const {
     auto I = SDEI.find(Node);
     return I != SDEI.end() ? I->second.HeapAllocSite : nullptr;
   }
   /// Set PCSections to be associated with Node.
   void addPCSections(const SDNode *Node, MDNode *MD) {
     SDEI[Node].PCSections = MD;
   }
   /// Set MMRAMetadata to be associated with Node.
   void addMMRAMetadata(const SDNode *Node, MDNode *MMRA) {
     SDEI[Node].MMRA = MMRA;
   }
   /// Return PCSections associated with Node, or nullptr if none exists.
   MDNode *getPCSections(const SDNode *Node) const {
     auto It = SDEI.find(Node);
     return It != SDEI.end() ? It->second.PCSections : nullptr;
   }
   /// Return the MMRA MDNode associated with Node, or nullptr if none
   /// exists.
   MDNode *getMMRAMetadata(const SDNode *Node) const {
     auto It = SDEI.find(Node);
     return It != SDEI.end() ? It->second.MMRA : nullptr;
   }
   /// Set CalledGlobal to be associated with Node.
   void addCalledGlobal(const SDNode *Node, const GlobalValue *GV,
                        unsigned OpFlags) {
     SDEI[Node].CalledGlobal = {GV, OpFlags};
   }
   /// Return CalledGlobal associated with Node, or a nullopt if none exists.
   std::optional<CalledGlobalInfo> getCalledGlobal(const SDNode *Node) {
     auto I = SDEI.find(Node);
     return I != SDEI.end()
                ? std::make_optional(std::move(I->second).CalledGlobal)
                : std::nullopt;
   }
   /// Set NoMergeSiteInfo to be associated with Node if NoMerge is true.
   void addNoMergeSiteInfo(const SDNode *Node, bool NoMerge) {
     if (NoMerge)
       SDEI[Node].NoMerge = NoMerge;
   }
   /// Return NoMerge info associated with Node.
   bool getNoMergeSiteInfo(const SDNode *Node) const {
     auto I = SDEI.find(Node);
     return I != SDEI.end() ? I->second.NoMerge : false;
   }
 
   /// Copy extra info associated with one node to another.
   void copyExtraInfo(SDNode *From, SDNode *To);
 
   /// Return the current function's default denormal handling kind for the given
   /// floating point type.
   DenormalMode getDenormalMode(EVT VT) const {
     return MF->getDenormalMode(VT.getFltSemantics());
   }
 
   bool shouldOptForSize() const;
 
   /// Get the (commutative) neutral element for the given opcode, if it exists.
   SDValue getNeutralElement(unsigned Opcode, const SDLoc &DL, EVT VT,
                             SDNodeFlags Flags);
 
   /// Some opcodes may create immediate undefined behavior when used with some
   /// values (integer division-by-zero for example). Therefore, these operations
   /// are not generally safe to move around or change.
   bool isSafeToSpeculativelyExecute(unsigned Opcode) const {
     switch (Opcode) {
     case ISD::SDIV:
     case ISD::SREM:
     case ISD::SDIVREM:
     case ISD::UDIV:
     case ISD::UREM:
     case ISD::UDIVREM:
       return false;
     default:
       return true;
     }
   }
 
   /// Check if the provided node is save to speculatively executed given its
   /// current arguments. So, while `udiv` the opcode is not safe to
   /// speculatively execute, a given `udiv` node may be if the denominator is
   /// known nonzero.
   bool isSafeToSpeculativelyExecuteNode(const SDNode *N) const {
     switch (N->getOpcode()) {
     case ISD::UDIV:
       return isKnownNeverZero(N->getOperand(1));
     default:
       return isSafeToSpeculativelyExecute(N->getOpcode());
     }
   }
 
   SDValue makeStateFunctionCall(unsigned LibFunc, SDValue Ptr, SDValue InChain,
                                 const SDLoc &DLoc);
 
 private:
   void InsertNode(SDNode *N);
   bool RemoveNodeFromCSEMaps(SDNode *N);
   void AddModifiedNodeToCSEMaps(SDNode *N);
   SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op, void *&InsertPos);
   SDNode *FindModifiedNodeSlot(SDNode *N, SDValue Op1, SDValue Op2,
                                void *&InsertPos);
   SDNode *FindModifiedNodeSlot(SDNode *N, ArrayRef<SDValue> Ops,
                                void *&InsertPos);
   SDNode *UpdateSDLocOnMergeSDNode(SDNode *N, const SDLoc &loc);
 
   void DeleteNodeNotInCSEMaps(SDNode *N);
   void DeallocateNode(SDNode *N);
 
   void allnodes_clear();
 
   /// Look up the node specified by ID in CSEMap.  If it exists, return it.  If
   /// not, return the insertion token that will make insertion faster.  This
   /// overload is for nodes other than Constant or ConstantFP, use the other one
   /// for those.
   SDNode *FindNodeOrInsertPos(const FoldingSetNodeID &ID, void *&InsertPos);
 
   /// Look up the node specified by ID in CSEMap.  If it exists, return it.  If
   /// not, return the insertion token that will make insertion faster.  Performs
   /// additional processing for constant nodes.
   SDNode *FindNodeOrInsertPos(const FoldingSetNodeID &ID, const SDLoc &DL,
                               void *&InsertPos);
 
   /// Maps to auto-CSE operations.
   std::vector<CondCodeSDNode*> CondCodeNodes;
 
   std::vector<SDNode*> ValueTypeNodes;
   std::map<EVT, SDNode*, EVT::compareRawBits> ExtendedValueTypeNodes;
   StringMap<SDNode*> ExternalSymbols;
 
   std::map<std::pair<std::string, unsigned>, SDNode *> TargetExternalSymbols;
   DenseMap<MCSymbol *, SDNode *> MCSymbols;
 
   FlagInserter *Inserter = nullptr;
 };
 
 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
   using nodes_iterator = pointer_iterator<SelectionDAG::allnodes_iterator>;
 
   static nodes_iterator nodes_begin(SelectionDAG *G) {
     return nodes_iterator(G->allnodes_begin());
   }
 
   static nodes_iterator nodes_end(SelectionDAG *G) {
     return nodes_iterator(G->allnodes_end());
   }
 };
 
 } // end namespace llvm
 
 #endif // LLVM_CODEGEN_SELECTIONDAG_H