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1//===- SplitKit.h - Toolkit for splitting live ranges -----------*- C++ -*-===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This file contains the SplitAnalysis class as well as mutator functions for10// live range splitting.11//12//===----------------------------------------------------------------------===//13 14#ifndef LLVM_LIB_CODEGEN_SPLITKIT_H15#define LLVM_LIB_CODEGEN_SPLITKIT_H16 17#include "llvm/ADT/ArrayRef.h"18#include "llvm/ADT/BitVector.h"19#include "llvm/ADT/DenseMap.h"20#include "llvm/ADT/DenseSet.h"21#include "llvm/ADT/IntervalMap.h"22#include "llvm/ADT/PointerIntPair.h"23#include "llvm/ADT/SmallPtrSet.h"24#include "llvm/ADT/SmallVector.h"25#include "llvm/CodeGen/LiveIntervalCalc.h"26#include "llvm/CodeGen/LiveIntervals.h"27#include "llvm/CodeGen/MachineBasicBlock.h"28#include "llvm/CodeGen/MachineFunction.h"29#include "llvm/CodeGen/SlotIndexes.h"30#include "llvm/Support/Compiler.h"31#include <utility>32 33namespace llvm {34 35class LiveInterval;36class LiveRange;37class LiveIntervals;38class LiveRangeEdit;39class MachineBlockFrequencyInfo;40class MachineDominatorTree;41class MachineLoopInfo;42class MachineRegisterInfo;43class TargetInstrInfo;44class TargetRegisterInfo;45class VirtRegMap;46class VirtRegAuxInfo;47 48/// Determines the latest safe point in a block in which we can insert a split,49/// spill or other instruction related with CurLI.50class LLVM_LIBRARY_VISIBILITY InsertPointAnalysis {51private:52  const LiveIntervals &LIS;53 54  /// Last legal insert point in each basic block in the current function.55  /// The first entry is the first terminator, the second entry is the56  /// last valid point to insert a split or spill for a variable that is57  /// live into a landing pad or inlineasm_br successor.58  SmallVector<std::pair<SlotIndex, SlotIndex>, 8> LastInsertPoint;59 60  SlotIndex computeLastInsertPoint(const LiveInterval &CurLI,61                                   const MachineBasicBlock &MBB);62 63public:64  InsertPointAnalysis(const LiveIntervals &lis, unsigned BBNum);65 66  /// Return the base index of the last valid insert point for \pCurLI in \pMBB.67  SlotIndex getLastInsertPoint(const LiveInterval &CurLI,68                               const MachineBasicBlock &MBB) {69    unsigned Num = MBB.getNumber();70    // Inline the common simple case.71    if (LastInsertPoint[Num].first.isValid() &&72        !LastInsertPoint[Num].second.isValid())73      return LastInsertPoint[Num].first;74    return computeLastInsertPoint(CurLI, MBB);75  }76 77  /// Returns the last insert point as an iterator for \pCurLI in \pMBB.78  MachineBasicBlock::iterator getLastInsertPointIter(const LiveInterval &CurLI,79                                                     MachineBasicBlock &MBB);80 81  /// Return the base index of the first insert point in \pMBB.82  SlotIndex getFirstInsertPoint(MachineBasicBlock &MBB) {83    SlotIndex Res = LIS.getMBBStartIdx(&MBB);84    if (!MBB.empty()) {85      MachineBasicBlock::iterator MII = MBB.SkipPHIsLabelsAndDebug(MBB.begin());86      if (MII != MBB.end())87        Res = LIS.getInstructionIndex(*MII);88    }89    return Res;90  }91 92};93 94/// SplitAnalysis - Analyze a LiveInterval, looking for live range splitting95/// opportunities.96class LLVM_LIBRARY_VISIBILITY SplitAnalysis {97public:98  const MachineFunction &MF;99  const VirtRegMap &VRM;100  const LiveIntervals &LIS;101  const MachineLoopInfo &Loops;102  const TargetInstrInfo &TII;103 104  /// Additional information about basic blocks where the current variable is105  /// live. Such a block will look like one of these templates:106  ///107  ///  1. |   o---x   | Internal to block. Variable is only live in this block.108  ///  2. |---x       | Live-in, kill.109  ///  3. |       o---| Def, live-out.110  ///  4. |---x   o---| Live-in, kill, def, live-out. Counted by NumGapBlocks.111  ///  5. |---o---o---| Live-through with uses or defs.112  ///  6. |-----------| Live-through without uses. Counted by NumThroughBlocks.113  ///114  /// Two BlockInfo entries are created for template 4. One for the live-in115  /// segment, and one for the live-out segment. These entries look as if the116  /// block were split in the middle where the live range isn't live.117  ///118  /// Live-through blocks without any uses don't get BlockInfo entries. They119  /// are simply listed in ThroughBlocks instead.120  ///121  struct BlockInfo {122    MachineBasicBlock *MBB;123    SlotIndex FirstInstr; ///< First instr accessing current reg.124    SlotIndex LastInstr;  ///< Last instr accessing current reg.125    SlotIndex FirstDef;   ///< First non-phi valno->def, or SlotIndex().126    bool LiveIn;          ///< Current reg is live in.127    bool LiveOut;         ///< Current reg is live out.128 129    /// isOneInstr - Returns true when this BlockInfo describes a single130    /// instruction.131    bool isOneInstr() const {132      return SlotIndex::isSameInstr(FirstInstr, LastInstr);133    }134 135    void print(raw_ostream &OS) const;136    void dump() const;137  };138 139private:140  // Current live interval.141  const LiveInterval *CurLI = nullptr;142 143  /// Insert Point Analysis.144  InsertPointAnalysis IPA;145 146  // Sorted slot indexes of using instructions.147  SmallVector<SlotIndex, 8> UseSlots;148 149  /// UseBlocks - Blocks where CurLI has uses.150  SmallVector<BlockInfo, 8> UseBlocks;151 152  /// NumGapBlocks - Number of duplicate entries in UseBlocks for blocks where153  /// the live range has a gap.154  unsigned NumGapBlocks = 0u;155 156  /// ThroughBlocks - Block numbers where CurLI is live through without uses.157  BitVector ThroughBlocks;158 159  /// NumThroughBlocks - Number of live-through blocks.160  unsigned NumThroughBlocks = 0u;161 162  /// LooksLikeLoopIV - The variable defines what looks like it could be a loop163  /// IV, where it defs a variable in the latch.164  bool LooksLikeLoopIV = false;165 166  // Sumarize statistics by counting instructions using CurLI.167  void analyzeUses();168 169  /// calcLiveBlockInfo - Compute per-block information about CurLI.170  void calcLiveBlockInfo();171 172public:173  SplitAnalysis(const VirtRegMap &vrm, const LiveIntervals &lis,174                const MachineLoopInfo &mli);175 176  /// analyze - set CurLI to the specified interval, and analyze how it may be177  /// split.178  void analyze(const LiveInterval *li);179 180  /// clear - clear all data structures so SplitAnalysis is ready to analyze a181  /// new interval.182  void clear();183 184  /// getParent - Return the last analyzed interval.185  const LiveInterval &getParent() const { return *CurLI; }186 187  /// isOriginalEndpoint - Return true if the original live range was killed or188  /// (re-)defined at Idx. Idx should be the 'def' slot for a normal kill/def,189  /// and 'use' for an early-clobber def.190  /// This can be used to recognize code inserted by earlier live range191  /// splitting.192  bool isOriginalEndpoint(SlotIndex Idx) const;193 194  /// getUseSlots - Return an array of SlotIndexes of instructions using CurLI.195  /// This include both use and def operands, at most one entry per instruction.196  ArrayRef<SlotIndex> getUseSlots() const { return UseSlots; }197 198  /// getUseBlocks - Return an array of BlockInfo objects for the basic blocks199  /// where CurLI has uses.200  ArrayRef<BlockInfo> getUseBlocks() const { return UseBlocks; }201 202  /// getNumThroughBlocks - Return the number of through blocks.203  unsigned getNumThroughBlocks() const { return NumThroughBlocks; }204 205  /// isThroughBlock - Return true if CurLI is live through MBB without uses.206  bool isThroughBlock(unsigned MBB) const { return ThroughBlocks.test(MBB); }207 208  /// getThroughBlocks - Return the set of through blocks.209  const BitVector &getThroughBlocks() const { return ThroughBlocks; }210 211  /// getNumLiveBlocks - Return the number of blocks where CurLI is live.212  unsigned getNumLiveBlocks() const {213    return getUseBlocks().size() - NumGapBlocks + getNumThroughBlocks();214  }215 216  bool looksLikeLoopIV() const { return LooksLikeLoopIV; }217 218  /// countLiveBlocks - Return the number of blocks where li is live. This is219  /// guaranteed to return the same number as getNumLiveBlocks() after calling220  /// analyze(li).221  unsigned countLiveBlocks(const LiveInterval *li) const;222 223  using BlockPtrSet = SmallPtrSet<const MachineBasicBlock *, 16>;224 225  /// shouldSplitSingleBlock - Returns true if it would help to create a local226  /// live range for the instructions in BI. There is normally no benefit to227  /// creating a live range for a single instruction, but it does enable228  /// register class inflation if the instruction has a restricted register229  /// class.230  ///231  /// @param BI           The block to be isolated.232  /// @param SingleInstrs True when single instructions should be isolated.233  bool shouldSplitSingleBlock(const BlockInfo &BI, bool SingleInstrs) const;234 235  SlotIndex getLastSplitPoint(unsigned Num) {236    return IPA.getLastInsertPoint(*CurLI, *MF.getBlockNumbered(Num));237  }238 239  SlotIndex getLastSplitPoint(MachineBasicBlock *BB) {240    return IPA.getLastInsertPoint(*CurLI, *BB);241  }242 243  MachineBasicBlock::iterator getLastSplitPointIter(MachineBasicBlock *BB) {244    return IPA.getLastInsertPointIter(*CurLI, *BB);245  }246 247  SlotIndex getFirstSplitPoint(unsigned Num) {248    return IPA.getFirstInsertPoint(*MF.getBlockNumbered(Num));249  }250};251 252/// SplitEditor - Edit machine code and LiveIntervals for live range253/// splitting.254///255/// - Create a SplitEditor from a SplitAnalysis.256/// - Start a new live interval with openIntv.257/// - Mark the places where the new interval is entered using enterIntv*258/// - Mark the ranges where the new interval is used with useIntv*259/// - Mark the places where the interval is exited with exitIntv*.260/// - Finish the current interval with closeIntv and repeat from 2.261/// - Rewrite instructions with finish().262///263class LLVM_LIBRARY_VISIBILITY SplitEditor {264  SplitAnalysis &SA;265  LiveIntervals &LIS;266  VirtRegMap &VRM;267  MachineRegisterInfo &MRI;268  MachineDominatorTree &MDT;269  const TargetInstrInfo &TII;270  const TargetRegisterInfo &TRI;271  const MachineBlockFrequencyInfo &MBFI;272  VirtRegAuxInfo &VRAI;273 274public:275  /// ComplementSpillMode - Select how the complement live range should be276  /// created.  SplitEditor automatically creates interval 0 to contain277  /// anything that isn't added to another interval.  This complement interval278  /// can get quite complicated, and it can sometimes be an advantage to allow279  /// it to overlap the other intervals.  If it is going to spill anyway, no280  /// registers are wasted by keeping a value in two places at the same time.281  enum ComplementSpillMode {282    /// SM_Partition(Default) - Try to create the complement interval so it283    /// doesn't overlap any other intervals, and the original interval is284    /// partitioned.  This may require a large number of back copies and extra285    /// PHI-defs.  Only segments marked with overlapIntv will be overlapping.286    SM_Partition,287 288    /// SM_Size - Overlap intervals to minimize the number of inserted COPY289    /// instructions.  Copies to the complement interval are hoisted to their290    /// common dominator, so only one COPY is required per value in the291    /// complement interval.  This also means that no extra PHI-defs need to be292    /// inserted in the complement interval.293    SM_Size,294 295    /// SM_Speed - Overlap intervals to minimize the expected execution296    /// frequency of the inserted copies.  This is very similar to SM_Size, but297    /// the complement interval may get some extra PHI-defs.298    SM_Speed299  };300 301private:302  /// Edit - The current parent register and new intervals created.303  LiveRangeEdit *Edit = nullptr;304 305  /// Index into Edit of the currently open interval.306  /// The index 0 is used for the complement, so the first interval started by307  /// openIntv will be 1.308  unsigned OpenIdx = 0;309 310  /// The current spill mode, selected by reset().311  ComplementSpillMode SpillMode = SM_Partition;312 313  using RegAssignMap = IntervalMap<SlotIndex, unsigned>;314 315  /// Allocator for the interval map. This will eventually be shared with316  /// SlotIndexes and LiveIntervals.317  RegAssignMap::Allocator Allocator;318 319  /// RegAssign - Map of the assigned register indexes.320  /// Edit.get(RegAssign.lookup(Idx)) is the register that should be live at321  /// Idx.322  RegAssignMap RegAssign;323 324  using ValueForcePair = PointerIntPair<VNInfo *, 1>;325  using ValueMap = DenseMap<std::pair<unsigned, unsigned>, ValueForcePair>;326 327  /// Values - keep track of the mapping from parent values to values in the new328  /// intervals. Given a pair (RegIdx, ParentVNI->id), Values contains:329  ///330  /// 1. No entry - the value is not mapped to Edit.get(RegIdx).331  /// 2. (Null, false) - the value is mapped to multiple values in332  ///    Edit.get(RegIdx).  Each value is represented by a minimal live range at333  ///    its def.  The full live range can be inferred exactly from the range334  ///    of RegIdx in RegAssign.335  /// 3. (Null, true).  As above, but the ranges in RegAssign are too large, and336  ///    the live range must be recomputed using ::extend().337  /// 4. (VNI, false) The value is mapped to a single new value.338  ///    The new value has no live ranges anywhere.339  ValueMap Values;340 341  /// LICalc - Cache for computing live ranges and SSA update.  Each instance342  /// can only handle non-overlapping live ranges, so use a separate343  /// LiveIntervalCalc instance for the complement interval when in spill mode.344  LiveIntervalCalc LICalc[2];345 346  /// getLICalc - Return the LICalc to use for RegIdx.  In spill mode, the347  /// complement interval can overlap the other intervals, so it gets its own348  /// LICalc instance.  When not in spill mode, all intervals can share one.349  LiveIntervalCalc &getLICalc(unsigned RegIdx) {350    return LICalc[SpillMode != SM_Partition && RegIdx != 0];351  }352 353  /// Add a segment to the interval LI for the value number VNI. If LI has354  /// subranges, corresponding segments will be added to them as well, but355  /// with newly created value numbers. If Original is true, dead def will356  /// only be added a subrange of LI if the corresponding subrange of the357  /// original interval has a def at this index. Otherwise, all subranges358  /// of LI will be updated.359  void addDeadDef(LiveInterval &LI, VNInfo *VNI, bool Original);360 361  /// defValue - define a value in RegIdx from ParentVNI at Idx.362  /// Idx does not have to be ParentVNI->def, but it must be contained within363  /// ParentVNI's live range in ParentLI. The new value is added to the value364  /// map. The value being defined may either come from rematerialization365  /// (or an inserted copy), or it may be coming from the original interval.366  /// The parameter Original should be true in the latter case, otherwise367  /// it should be false.368  /// Return the new LI value.369  VNInfo *defValue(unsigned RegIdx, const VNInfo *ParentVNI, SlotIndex Idx,370                   bool Original);371 372  /// forceRecompute - Force the live range of ParentVNI in RegIdx to be373  /// recomputed by LiveRangeCalc::extend regardless of the number of defs.374  /// This is used for values whose live range doesn't match RegAssign exactly.375  /// They could have rematerialized, or back-copies may have been moved.376  void forceRecompute(unsigned RegIdx, const VNInfo &ParentVNI);377 378  /// Calls forceRecompute() on any affected regidx and on ParentVNI379  /// predecessors in case of a phi definition.380  void forceRecomputeVNI(const VNInfo &ParentVNI);381 382  /// \return true if rematerializing \p DefMI at \p UseIdx will make the383  /// register class requirements stricter at the use.384  bool rematWillIncreaseRestriction(const MachineInstr *DefMI,385                                    MachineBasicBlock &MBB,386                                    SlotIndex UseIdx) const;387 388  /// defFromParent - Define Reg from ParentVNI at UseIdx using either389  /// rematerialization or a COPY from parent. Return the new value.390  VNInfo *defFromParent(unsigned RegIdx, const VNInfo *ParentVNI,391                        SlotIndex UseIdx, MachineBasicBlock &MBB,392                        MachineBasicBlock::iterator I);393 394  /// removeBackCopies - Remove the copy instructions that defines the values395  /// in the vector in the complement interval.396  void removeBackCopies(SmallVectorImpl<VNInfo*> &Copies);397 398  /// getShallowDominator - Returns the least busy dominator of MBB that is399  /// also dominated by DefMBB.  Busy is measured by loop depth.400  MachineBasicBlock *findShallowDominator(MachineBasicBlock *MBB,401                                          MachineBasicBlock *DefMBB);402 403  /// Find out all the backCopies dominated by others.404  void computeRedundantBackCopies(DenseSet<unsigned> &NotToHoistSet,405                                  SmallVectorImpl<VNInfo *> &BackCopies);406 407  /// Hoist back-copies to the complement interval. It tries to hoist all408  /// the back-copies to one BB if it is beneficial, or else simply remove409  /// redundant backcopies dominated by others.410  void hoistCopies();411 412  /// transferValues - Transfer values to the new ranges.413  /// Return true if any ranges were skipped.414  bool transferValues();415 416  /// Live range @p LR corresponding to the lane Mask @p LM has a live417  /// PHI def at the beginning of block @p B. Extend the range @p LR of418  /// all predecessor values that reach this def. If @p LR is a subrange,419  /// the array @p Undefs is the set of all locations where it is undefined420  /// via <def,read-undef> in other subranges for the same register.421  void extendPHIRange(MachineBasicBlock &B, LiveIntervalCalc &LIC,422                      LiveRange &LR, LaneBitmask LM,423                      ArrayRef<SlotIndex> Undefs);424 425  /// extendPHIKillRanges - Extend the ranges of all values killed by original426  /// parent PHIDefs.427  void extendPHIKillRanges();428 429  /// rewriteAssigned - Rewrite all uses of Edit.getReg() to assigned registers.430  void rewriteAssigned(bool ExtendRanges);431 432  /// deleteRematVictims - Delete defs that are dead after rematerializing.433  void deleteRematVictims();434 435  /// Add a copy instruction copying \p FromReg to \p ToReg before436  /// \p InsertBefore. This can be invoked with a \p LaneMask which may make it437  /// necessary to construct a sequence of copies to cover it exactly.438  SlotIndex buildCopy(Register FromReg, Register ToReg, LaneBitmask LaneMask,439      MachineBasicBlock &MBB, MachineBasicBlock::iterator InsertBefore,440      bool Late, unsigned RegIdx);441 442  SlotIndex buildSingleSubRegCopy(Register FromReg, Register ToReg,443                                  MachineBasicBlock &MB,444                                  MachineBasicBlock::iterator InsertBefore,445                                  unsigned SubIdx, LiveInterval &DestLI,446                                  bool Late, SlotIndex Def,447                                  const MCInstrDesc &Desc);448 449public:450  /// Create a new SplitEditor for editing the LiveInterval analyzed by SA.451  /// Newly created intervals will be appended to newIntervals.452  SplitEditor(SplitAnalysis &SA, LiveIntervals &LIS, VirtRegMap &VRM,453              MachineDominatorTree &MDT, MachineBlockFrequencyInfo &MBFI,454              VirtRegAuxInfo &VRAI);455 456  /// reset - Prepare for a new split.457  void reset(LiveRangeEdit&, ComplementSpillMode = SM_Partition);458 459  /// Create a new virtual register and live interval.460  /// Return the interval index, starting from 1. Interval index 0 is the461  /// implicit complement interval.462  unsigned openIntv();463 464  /// currentIntv - Return the current interval index.465  unsigned currentIntv() const { return OpenIdx; }466 467  /// selectIntv - Select a previously opened interval index.468  void selectIntv(unsigned Idx);469 470  /// enterIntvBefore - Enter the open interval before the instruction at Idx.471  /// If the parent interval is not live before Idx, a COPY is not inserted.472  /// Return the beginning of the new live range.473  SlotIndex enterIntvBefore(SlotIndex Idx);474 475  /// enterIntvAfter - Enter the open interval after the instruction at Idx.476  /// Return the beginning of the new live range.477  SlotIndex enterIntvAfter(SlotIndex Idx);478 479  /// enterIntvAtEnd - Enter the open interval at the end of MBB.480  /// Use the open interval from the inserted copy to the MBB end.481  /// Return the beginning of the new live range.482  SlotIndex enterIntvAtEnd(MachineBasicBlock &MBB);483 484  /// useIntv - indicate that all instructions in MBB should use OpenLI.485  void useIntv(const MachineBasicBlock &MBB);486 487  /// useIntv - indicate that all instructions in range should use OpenLI.488  void useIntv(SlotIndex Start, SlotIndex End);489 490  /// leaveIntvAfter - Leave the open interval after the instruction at Idx.491  /// Return the end of the live range.492  SlotIndex leaveIntvAfter(SlotIndex Idx);493 494  /// leaveIntvBefore - Leave the open interval before the instruction at Idx.495  /// Return the end of the live range.496  SlotIndex leaveIntvBefore(SlotIndex Idx);497 498  /// leaveIntvAtTop - Leave the interval at the top of MBB.499  /// Add liveness from the MBB top to the copy.500  /// Return the end of the live range.501  SlotIndex leaveIntvAtTop(MachineBasicBlock &MBB);502 503  /// overlapIntv - Indicate that all instructions in range should use the open504  /// interval if End does not have tied-def usage of the register and in this505  /// case complement interval is used. Let the complement interval be live.506  ///507  /// This doubles the register pressure, but is sometimes required to deal with508  /// register uses after the last valid split point.509  ///510  /// The Start index should be a return value from a leaveIntv* call, and End511  /// should be in the same basic block. The parent interval must have the same512  /// value across the range.513  ///514  void overlapIntv(SlotIndex Start, SlotIndex End);515 516  /// finish - after all the new live ranges have been created, compute the517  /// remaining live range, and rewrite instructions to use the new registers.518  /// @param LRMap When not null, this vector will map each live range in Edit519  ///              back to the indices returned by openIntv.520  ///              There may be extra indices created by dead code elimination.521  void finish(SmallVectorImpl<unsigned> *LRMap = nullptr);522 523  /// dump - print the current interval mapping to dbgs().524  void dump() const;525 526  // ===--- High level methods ---===527 528  /// splitSingleBlock - Split CurLI into a separate live interval around the529  /// uses in a single block. This is intended to be used as part of a larger530  /// split, and doesn't call finish().531  void splitSingleBlock(const SplitAnalysis::BlockInfo &BI);532 533  /// splitLiveThroughBlock - Split CurLI in the given block such that it534  /// enters the block in IntvIn and leaves it in IntvOut. There may be uses in535  /// the block, but they will be ignored when placing split points.536  ///537  /// @param MBBNum      Block number.538  /// @param IntvIn      Interval index entering the block.539  /// @param LeaveBefore When set, leave IntvIn before this point.540  /// @param IntvOut     Interval index leaving the block.541  /// @param EnterAfter  When set, enter IntvOut after this point.542  void splitLiveThroughBlock(unsigned MBBNum,543                             unsigned IntvIn, SlotIndex LeaveBefore,544                             unsigned IntvOut, SlotIndex EnterAfter);545 546  /// splitRegInBlock - Split CurLI in the given block such that it enters the547  /// block in IntvIn and leaves it on the stack (or not at all). Split points548  /// are placed in a way that avoids putting uses in the stack interval. This549  /// may require creating a local interval when there is interference.550  ///551  /// @param BI          Block descriptor.552  /// @param IntvIn      Interval index entering the block. Not 0.553  /// @param LeaveBefore When set, leave IntvIn before this point.554  void splitRegInBlock(const SplitAnalysis::BlockInfo &BI,555                       unsigned IntvIn, SlotIndex LeaveBefore);556 557  /// splitRegOutBlock - Split CurLI in the given block such that it enters the558  /// block on the stack (or isn't live-in at all) and leaves it in IntvOut.559  /// Split points are placed to avoid interference and such that the uses are560  /// not in the stack interval. This may require creating a local interval561  /// when there is interference.562  ///563  /// @param BI          Block descriptor.564  /// @param IntvOut     Interval index leaving the block.565  /// @param EnterAfter  When set, enter IntvOut after this point.566  void splitRegOutBlock(const SplitAnalysis::BlockInfo &BI,567                        unsigned IntvOut, SlotIndex EnterAfter);568};569 570} // end namespace llvm571 572#endif // LLVM_LIB_CODEGEN_SPLITKIT_H573