LLVM  6.0.0svn
SplitKit.h
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1 //===- SplitKit.h - Toolkit for splitting live ranges -----------*- C++ -*-===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file contains the SplitAnalysis class as well as mutator functions for
11 // live range splitting.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_LIB_CODEGEN_SPLITKIT_H
16 #define LLVM_LIB_CODEGEN_SPLITKIT_H
17 
18 #include "LiveRangeCalc.h"
19 #include "llvm/ADT/ArrayRef.h"
20 #include "llvm/ADT/BitVector.h"
21 #include "llvm/ADT/DenseMap.h"
22 #include "llvm/ADT/DenseSet.h"
23 #include "llvm/ADT/IntervalMap.h"
25 #include "llvm/ADT/SmallPtrSet.h"
26 #include "llvm/ADT/SmallVector.h"
31 #include "llvm/MC/LaneBitmask.h"
32 #include "llvm/Support/Compiler.h"
33 #include <utility>
34 
35 namespace llvm {
36 
37 class LiveIntervals;
38 class LiveRangeEdit;
39 class MachineBlockFrequencyInfo;
40 class MachineDominatorTree;
41 class MachineLoopInfo;
42 class MachineRegisterInfo;
43 class TargetInstrInfo;
44 class TargetRegisterInfo;
45 class VirtRegMap;
46 
47 /// Determines the latest safe point in a block in which we can insert a split,
48 /// spill or other instruction related with CurLI.
50 private:
51  const LiveIntervals &LIS;
52 
53  /// Last legal insert point in each basic block in the current function.
54  /// The first entry is the first terminator, the second entry is the
55  /// last valid point to insert a split or spill for a variable that is
56  /// live into a landing pad successor.
58 
59  SlotIndex computeLastInsertPoint(const LiveInterval &CurLI,
60  const MachineBasicBlock &MBB);
61 
62 public:
63  InsertPointAnalysis(const LiveIntervals &lis, unsigned BBNum);
64 
65  /// Return the base index of the last valid insert point for \pCurLI in \pMBB.
67  const MachineBasicBlock &MBB) {
68  unsigned Num = MBB.getNumber();
69  // Inline the common simple case.
70  if (LastInsertPoint[Num].first.isValid() &&
71  !LastInsertPoint[Num].second.isValid())
72  return LastInsertPoint[Num].first;
73  return computeLastInsertPoint(CurLI, MBB);
74  }
75 
76  /// Returns the last insert point as an iterator for \pCurLI in \pMBB.
77  MachineBasicBlock::iterator getLastInsertPointIter(const LiveInterval &CurLI,
78  MachineBasicBlock &MBB);
79 };
80 
81 /// SplitAnalysis - Analyze a LiveInterval, looking for live range splitting
82 /// opportunities.
84 public:
86  const VirtRegMap &VRM;
90 
91  /// Additional information about basic blocks where the current variable is
92  /// live. Such a block will look like one of these templates:
93  ///
94  /// 1. | o---x | Internal to block. Variable is only live in this block.
95  /// 2. |---x | Live-in, kill.
96  /// 3. | o---| Def, live-out.
97  /// 4. |---x o---| Live-in, kill, def, live-out. Counted by NumGapBlocks.
98  /// 5. |---o---o---| Live-through with uses or defs.
99  /// 6. |-----------| Live-through without uses. Counted by NumThroughBlocks.
100  ///
101  /// Two BlockInfo entries are created for template 4. One for the live-in
102  /// segment, and one for the live-out segment. These entries look as if the
103  /// block were split in the middle where the live range isn't live.
104  ///
105  /// Live-through blocks without any uses don't get BlockInfo entries. They
106  /// are simply listed in ThroughBlocks instead.
107  ///
108  struct BlockInfo {
110  SlotIndex FirstInstr; ///< First instr accessing current reg.
111  SlotIndex LastInstr; ///< Last instr accessing current reg.
112  SlotIndex FirstDef; ///< First non-phi valno->def, or SlotIndex().
113  bool LiveIn; ///< Current reg is live in.
114  bool LiveOut; ///< Current reg is live out.
115 
116  /// isOneInstr - Returns true when this BlockInfo describes a single
117  /// instruction.
118  bool isOneInstr() const {
119  return SlotIndex::isSameInstr(FirstInstr, LastInstr);
120  }
121  };
122 
123 private:
124  // Current live interval.
125  const LiveInterval *CurLI = nullptr;
126 
127  /// Insert Point Analysis.
129 
130  // Sorted slot indexes of using instructions.
131  SmallVector<SlotIndex, 8> UseSlots;
132 
133  /// UseBlocks - Blocks where CurLI has uses.
134  SmallVector<BlockInfo, 8> UseBlocks;
135 
136  /// NumGapBlocks - Number of duplicate entries in UseBlocks for blocks where
137  /// the live range has a gap.
138  unsigned NumGapBlocks;
139 
140  /// ThroughBlocks - Block numbers where CurLI is live through without uses.
141  BitVector ThroughBlocks;
142 
143  /// NumThroughBlocks - Number of live-through blocks.
144  unsigned NumThroughBlocks;
145 
146  /// DidRepairRange - analyze was forced to shrinkToUses().
147  bool DidRepairRange;
148 
149  // Sumarize statistics by counting instructions using CurLI.
150  void analyzeUses();
151 
152  /// calcLiveBlockInfo - Compute per-block information about CurLI.
153  bool calcLiveBlockInfo();
154 
155 public:
156  SplitAnalysis(const VirtRegMap &vrm, const LiveIntervals &lis,
157  const MachineLoopInfo &mli);
158 
159  /// analyze - set CurLI to the specified interval, and analyze how it may be
160  /// split.
161  void analyze(const LiveInterval *li);
162 
163  /// didRepairRange() - Returns true if CurLI was invalid and has been repaired
164  /// by analyze(). This really shouldn't happen, but sometimes the coalescer
165  /// can create live ranges that end in mid-air.
166  bool didRepairRange() const { return DidRepairRange; }
167 
168  /// clear - clear all data structures so SplitAnalysis is ready to analyze a
169  /// new interval.
170  void clear();
171 
172  /// getParent - Return the last analyzed interval.
173  const LiveInterval &getParent() const { return *CurLI; }
174 
175  /// isOriginalEndpoint - Return true if the original live range was killed or
176  /// (re-)defined at Idx. Idx should be the 'def' slot for a normal kill/def,
177  /// and 'use' for an early-clobber def.
178  /// This can be used to recognize code inserted by earlier live range
179  /// splitting.
180  bool isOriginalEndpoint(SlotIndex Idx) const;
181 
182  /// getUseSlots - Return an array of SlotIndexes of instructions using CurLI.
183  /// This include both use and def operands, at most one entry per instruction.
184  ArrayRef<SlotIndex> getUseSlots() const { return UseSlots; }
185 
186  /// getUseBlocks - Return an array of BlockInfo objects for the basic blocks
187  /// where CurLI has uses.
188  ArrayRef<BlockInfo> getUseBlocks() const { return UseBlocks; }
189 
190  /// getNumThroughBlocks - Return the number of through blocks.
191  unsigned getNumThroughBlocks() const { return NumThroughBlocks; }
192 
193  /// isThroughBlock - Return true if CurLI is live through MBB without uses.
194  bool isThroughBlock(unsigned MBB) const { return ThroughBlocks.test(MBB); }
195 
196  /// getThroughBlocks - Return the set of through blocks.
197  const BitVector &getThroughBlocks() const { return ThroughBlocks; }
198 
199  /// getNumLiveBlocks - Return the number of blocks where CurLI is live.
200  unsigned getNumLiveBlocks() const {
201  return getUseBlocks().size() - NumGapBlocks + getNumThroughBlocks();
202  }
203 
204  /// countLiveBlocks - Return the number of blocks where li is live. This is
205  /// guaranteed to return the same number as getNumLiveBlocks() after calling
206  /// analyze(li).
207  unsigned countLiveBlocks(const LiveInterval *li) const;
208 
210 
211  /// shouldSplitSingleBlock - Returns true if it would help to create a local
212  /// live range for the instructions in BI. There is normally no benefit to
213  /// creating a live range for a single instruction, but it does enable
214  /// register class inflation if the instruction has a restricted register
215  /// class.
216  ///
217  /// @param BI The block to be isolated.
218  /// @param SingleInstrs True when single instructions should be isolated.
219  bool shouldSplitSingleBlock(const BlockInfo &BI, bool SingleInstrs) const;
220 
221  SlotIndex getLastSplitPoint(unsigned Num) {
222  return IPA.getLastInsertPoint(*CurLI, *MF.getBlockNumbered(Num));
223  }
224 
226  return IPA.getLastInsertPointIter(*CurLI, *BB);
227  }
228 };
229 
230 /// SplitEditor - Edit machine code and LiveIntervals for live range
231 /// splitting.
232 ///
233 /// - Create a SplitEditor from a SplitAnalysis.
234 /// - Start a new live interval with openIntv.
235 /// - Mark the places where the new interval is entered using enterIntv*
236 /// - Mark the ranges where the new interval is used with useIntv*
237 /// - Mark the places where the interval is exited with exitIntv*.
238 /// - Finish the current interval with closeIntv and repeat from 2.
239 /// - Rewrite instructions with finish().
240 ///
242  SplitAnalysis &SA;
243  AliasAnalysis &AA;
244  LiveIntervals &LIS;
245  VirtRegMap &VRM;
248  const TargetInstrInfo &TII;
249  const TargetRegisterInfo &TRI;
250  const MachineBlockFrequencyInfo &MBFI;
251 
252 public:
253  /// ComplementSpillMode - Select how the complement live range should be
254  /// created. SplitEditor automatically creates interval 0 to contain
255  /// anything that isn't added to another interval. This complement interval
256  /// can get quite complicated, and it can sometimes be an advantage to allow
257  /// it to overlap the other intervals. If it is going to spill anyway, no
258  /// registers are wasted by keeping a value in two places at the same time.
260  /// SM_Partition(Default) - Try to create the complement interval so it
261  /// doesn't overlap any other intervals, and the original interval is
262  /// partitioned. This may require a large number of back copies and extra
263  /// PHI-defs. Only segments marked with overlapIntv will be overlapping.
265 
266  /// SM_Size - Overlap intervals to minimize the number of inserted COPY
267  /// instructions. Copies to the complement interval are hoisted to their
268  /// common dominator, so only one COPY is required per value in the
269  /// complement interval. This also means that no extra PHI-defs need to be
270  /// inserted in the complement interval.
272 
273  /// SM_Speed - Overlap intervals to minimize the expected execution
274  /// frequency of the inserted copies. This is very similar to SM_Size, but
275  /// the complement interval may get some extra PHI-defs.
276  SM_Speed
277  };
278 
279 private:
280  /// Edit - The current parent register and new intervals created.
281  LiveRangeEdit *Edit = nullptr;
282 
283  /// Index into Edit of the currently open interval.
284  /// The index 0 is used for the complement, so the first interval started by
285  /// openIntv will be 1.
286  unsigned OpenIdx = 0;
287 
288  /// The current spill mode, selected by reset().
289  ComplementSpillMode SpillMode = SM_Partition;
290 
292 
293  /// Allocator for the interval map. This will eventually be shared with
294  /// SlotIndexes and LiveIntervals.
296 
297  /// RegAssign - Map of the assigned register indexes.
298  /// Edit.get(RegAssign.lookup(Idx)) is the register that should be live at
299  /// Idx.
300  RegAssignMap RegAssign;
301 
304 
305  /// Values - keep track of the mapping from parent values to values in the new
306  /// intervals. Given a pair (RegIdx, ParentVNI->id), Values contains:
307  ///
308  /// 1. No entry - the value is not mapped to Edit.get(RegIdx).
309  /// 2. (Null, false) - the value is mapped to multiple values in
310  /// Edit.get(RegIdx). Each value is represented by a minimal live range at
311  /// its def. The full live range can be inferred exactly from the range
312  /// of RegIdx in RegAssign.
313  /// 3. (Null, true). As above, but the ranges in RegAssign are too large, and
314  /// the live range must be recomputed using LiveRangeCalc::extend().
315  /// 4. (VNI, false) The value is mapped to a single new value.
316  /// The new value has no live ranges anywhere.
317  ValueMap Values;
318 
319  /// LRCalc - Cache for computing live ranges and SSA update. Each instance
320  /// can only handle non-overlapping live ranges, so use a separate
321  /// LiveRangeCalc instance for the complement interval when in spill mode.
322  LiveRangeCalc LRCalc[2];
323 
324  /// getLRCalc - Return the LRCalc to use for RegIdx. In spill mode, the
325  /// complement interval can overlap the other intervals, so it gets its own
326  /// LRCalc instance. When not in spill mode, all intervals can share one.
327  LiveRangeCalc &getLRCalc(unsigned RegIdx) {
328  return LRCalc[SpillMode != SM_Partition && RegIdx != 0];
329  }
330 
331  /// Find a subrange corresponding to the lane mask @p LM in the live
332  /// interval @p LI. The interval @p LI is assumed to contain such a subrange.
333  /// This function is used to find corresponding subranges between the
334  /// original interval and the new intervals.
335  LiveInterval::SubRange &getSubRangeForMask(LaneBitmask LM, LiveInterval &LI);
336 
337  /// Add a segment to the interval LI for the value number VNI. If LI has
338  /// subranges, corresponding segments will be added to them as well, but
339  /// with newly created value numbers. If Original is true, dead def will
340  /// only be added a subrange of LI if the corresponding subrange of the
341  /// original interval has a def at this index. Otherwise, all subranges
342  /// of LI will be updated.
343  void addDeadDef(LiveInterval &LI, VNInfo *VNI, bool Original);
344 
345  /// defValue - define a value in RegIdx from ParentVNI at Idx.
346  /// Idx does not have to be ParentVNI->def, but it must be contained within
347  /// ParentVNI's live range in ParentLI. The new value is added to the value
348  /// map. The value being defined may either come from rematerialization
349  /// (or an inserted copy), or it may be coming from the original interval.
350  /// The parameter Original should be true in the latter case, otherwise
351  /// it should be false.
352  /// Return the new LI value.
353  VNInfo *defValue(unsigned RegIdx, const VNInfo *ParentVNI, SlotIndex Idx,
354  bool Original);
355 
356  /// forceRecompute - Force the live range of ParentVNI in RegIdx to be
357  /// recomputed by LiveRangeCalc::extend regardless of the number of defs.
358  /// This is used for values whose live range doesn't match RegAssign exactly.
359  /// They could have rematerialized, or back-copies may have been moved.
360  void forceRecompute(unsigned RegIdx, const VNInfo *ParentVNI);
361 
362  /// defFromParent - Define Reg from ParentVNI at UseIdx using either
363  /// rematerialization or a COPY from parent. Return the new value.
364  VNInfo *defFromParent(unsigned RegIdx,
365  VNInfo *ParentVNI,
366  SlotIndex UseIdx,
367  MachineBasicBlock &MBB,
369 
370  /// removeBackCopies - Remove the copy instructions that defines the values
371  /// in the vector in the complement interval.
372  void removeBackCopies(SmallVectorImpl<VNInfo*> &Copies);
373 
374  /// getShallowDominator - Returns the least busy dominator of MBB that is
375  /// also dominated by DefMBB. Busy is measured by loop depth.
376  MachineBasicBlock *findShallowDominator(MachineBasicBlock *MBB,
377  MachineBasicBlock *DefMBB);
378 
379  /// Find out all the backCopies dominated by others.
380  void computeRedundantBackCopies(DenseSet<unsigned> &NotToHoistSet,
381  SmallVectorImpl<VNInfo *> &BackCopies);
382 
383  /// Hoist back-copies to the complement interval. It tries to hoist all
384  /// the back-copies to one BB if it is beneficial, or else simply remove
385  /// redundant backcopies dominated by others.
386  void hoistCopies();
387 
388  /// transferValues - Transfer values to the new ranges.
389  /// Return true if any ranges were skipped.
390  bool transferValues();
391 
392  /// Live range @p LR corresponding to the lane Mask @p LM has a live
393  /// PHI def at the beginning of block @p B. Extend the range @p LR of
394  /// all predecessor values that reach this def. If @p LR is a subrange,
395  /// the array @p Undefs is the set of all locations where it is undefined
396  /// via <def,read-undef> in other subranges for the same register.
397  void extendPHIRange(MachineBasicBlock &B, LiveRangeCalc &LRC,
398  LiveRange &LR, LaneBitmask LM,
399  ArrayRef<SlotIndex> Undefs);
400 
401  /// extendPHIKillRanges - Extend the ranges of all values killed by original
402  /// parent PHIDefs.
403  void extendPHIKillRanges();
404 
405  /// rewriteAssigned - Rewrite all uses of Edit.getReg() to assigned registers.
406  void rewriteAssigned(bool ExtendRanges);
407 
408  /// deleteRematVictims - Delete defs that are dead after rematerializing.
409  void deleteRematVictims();
410 
411  /// Add a copy instruction copying \p FromReg to \p ToReg before
412  /// \p InsertBefore. This can be invoked with a \p LaneMask which may make it
413  /// necessary to construct a sequence of copies to cover it exactly.
414  SlotIndex buildCopy(unsigned FromReg, unsigned ToReg, LaneBitmask LaneMask,
416  bool Late, unsigned RegIdx);
417 
418  SlotIndex buildSingleSubRegCopy(unsigned FromReg, unsigned ToReg,
420  unsigned SubIdx, LiveInterval &DestLI, bool Late, SlotIndex PrevCopy);
421 
422 public:
423  /// Create a new SplitEditor for editing the LiveInterval analyzed by SA.
424  /// Newly created intervals will be appended to newIntervals.
426  VirtRegMap &vrm, MachineDominatorTree &mdt,
428 
429  /// reset - Prepare for a new split.
430  void reset(LiveRangeEdit&, ComplementSpillMode = SM_Partition);
431 
432  /// Create a new virtual register and live interval.
433  /// Return the interval index, starting from 1. Interval index 0 is the
434  /// implicit complement interval.
435  unsigned openIntv();
436 
437  /// currentIntv - Return the current interval index.
438  unsigned currentIntv() const { return OpenIdx; }
439 
440  /// selectIntv - Select a previously opened interval index.
441  void selectIntv(unsigned Idx);
442 
443  /// enterIntvBefore - Enter the open interval before the instruction at Idx.
444  /// If the parent interval is not live before Idx, a COPY is not inserted.
445  /// Return the beginning of the new live range.
446  SlotIndex enterIntvBefore(SlotIndex Idx);
447 
448  /// enterIntvAfter - Enter the open interval after the instruction at Idx.
449  /// Return the beginning of the new live range.
450  SlotIndex enterIntvAfter(SlotIndex Idx);
451 
452  /// enterIntvAtEnd - Enter the open interval at the end of MBB.
453  /// Use the open interval from the inserted copy to the MBB end.
454  /// Return the beginning of the new live range.
455  SlotIndex enterIntvAtEnd(MachineBasicBlock &MBB);
456 
457  /// useIntv - indicate that all instructions in MBB should use OpenLI.
458  void useIntv(const MachineBasicBlock &MBB);
459 
460  /// useIntv - indicate that all instructions in range should use OpenLI.
461  void useIntv(SlotIndex Start, SlotIndex End);
462 
463  /// leaveIntvAfter - Leave the open interval after the instruction at Idx.
464  /// Return the end of the live range.
465  SlotIndex leaveIntvAfter(SlotIndex Idx);
466 
467  /// leaveIntvBefore - Leave the open interval before the instruction at Idx.
468  /// Return the end of the live range.
469  SlotIndex leaveIntvBefore(SlotIndex Idx);
470 
471  /// leaveIntvAtTop - Leave the interval at the top of MBB.
472  /// Add liveness from the MBB top to the copy.
473  /// Return the end of the live range.
474  SlotIndex leaveIntvAtTop(MachineBasicBlock &MBB);
475 
476  /// overlapIntv - Indicate that all instructions in range should use the open
477  /// interval, but also let the complement interval be live.
478  ///
479  /// This doubles the register pressure, but is sometimes required to deal with
480  /// register uses after the last valid split point.
481  ///
482  /// The Start index should be a return value from a leaveIntv* call, and End
483  /// should be in the same basic block. The parent interval must have the same
484  /// value across the range.
485  ///
486  void overlapIntv(SlotIndex Start, SlotIndex End);
487 
488  /// finish - after all the new live ranges have been created, compute the
489  /// remaining live range, and rewrite instructions to use the new registers.
490  /// @param LRMap When not null, this vector will map each live range in Edit
491  /// back to the indices returned by openIntv.
492  /// There may be extra indices created by dead code elimination.
493  void finish(SmallVectorImpl<unsigned> *LRMap = nullptr);
494 
495  /// dump - print the current interval mapping to dbgs().
496  void dump() const;
497 
498  // ===--- High level methods ---===
499 
500  /// splitSingleBlock - Split CurLI into a separate live interval around the
501  /// uses in a single block. This is intended to be used as part of a larger
502  /// split, and doesn't call finish().
503  void splitSingleBlock(const SplitAnalysis::BlockInfo &BI);
504 
505  /// splitLiveThroughBlock - Split CurLI in the given block such that it
506  /// enters the block in IntvIn and leaves it in IntvOut. There may be uses in
507  /// the block, but they will be ignored when placing split points.
508  ///
509  /// @param MBBNum Block number.
510  /// @param IntvIn Interval index entering the block.
511  /// @param LeaveBefore When set, leave IntvIn before this point.
512  /// @param IntvOut Interval index leaving the block.
513  /// @param EnterAfter When set, enter IntvOut after this point.
514  void splitLiveThroughBlock(unsigned MBBNum,
515  unsigned IntvIn, SlotIndex LeaveBefore,
516  unsigned IntvOut, SlotIndex EnterAfter);
517 
518  /// splitRegInBlock - Split CurLI in the given block such that it enters the
519  /// block in IntvIn and leaves it on the stack (or not at all). Split points
520  /// are placed in a way that avoids putting uses in the stack interval. This
521  /// may require creating a local interval when there is interference.
522  ///
523  /// @param BI Block descriptor.
524  /// @param IntvIn Interval index entering the block. Not 0.
525  /// @param LeaveBefore When set, leave IntvIn before this point.
526  void splitRegInBlock(const SplitAnalysis::BlockInfo &BI,
527  unsigned IntvIn, SlotIndex LeaveBefore);
528 
529  /// splitRegOutBlock - Split CurLI in the given block such that it enters the
530  /// block on the stack (or isn't live-in at all) and leaves it in IntvOut.
531  /// Split points are placed to avoid interference and such that the uses are
532  /// not in the stack interval. This may require creating a local interval
533  /// when there is interference.
534  ///
535  /// @param BI Block descriptor.
536  /// @param IntvOut Interval index leaving the block.
537  /// @param EnterAfter When set, enter IntvOut after this point.
538  void splitRegOutBlock(const SplitAnalysis::BlockInfo &BI,
539  unsigned IntvOut, SlotIndex EnterAfter);
540 };
541 
542 } // end namespace llvm
543 
544 #endif // LLVM_LIB_CODEGEN_SPLITKIT_H
A common definition of LaneBitmask for use in TableGen and CodeGen.
Compute iterated dominance frontiers using a linear time algorithm.
Definition: AllocatorList.h:24
SlotIndex getLastSplitPoint(unsigned Num)
Definition: SplitKit.h:221
LiveInterval - This class represents the liveness of a register, or stack slot.
Definition: LiveInterval.h:638
bool test(unsigned Idx) const
Definition: BitVector.h:502
SlotIndex FirstDef
First non-phi valno->def, or SlotIndex().
Definition: SplitKit.h:112
MachineBlockFrequencyInfo pass uses BlockFrequencyInfoImpl implementation to estimate machine basic b...
const MachineLoopInfo & Loops
Definition: SplitKit.h:88
ComplementSpillMode
ComplementSpillMode - Select how the complement live range should be created.
Definition: SplitKit.h:259
A live range for subregisters.
Definition: LiveInterval.h:645
VNInfo - Value Number Information.
Definition: LiveInterval.h:53
Determines the latest safe point in a block in which we can insert a split, spill or other instructio...
Definition: SplitKit.h:49
This class represents the liveness of a register, stack slot, etc.
Definition: LiveInterval.h:157
unsigned getNumLiveBlocks() const
getNumLiveBlocks - Return the number of blocks where CurLI is live.
Definition: SplitKit.h:200
ArrayRef< SlotIndex > getUseSlots() const
getUseSlots - Return an array of SlotIndexes of instructions using CurLI.
Definition: SplitKit.h:184
const BitVector & getThroughBlocks() const
getThroughBlocks - Return the set of through blocks.
Definition: SplitKit.h:197
const HexagonInstrInfo * TII
const TargetInstrInfo & TII
Definition: SplitKit.h:89
SlotIndex getLastInsertPoint(const LiveInterval &CurLI, const MachineBasicBlock &MBB)
Return the base index of the last valid insert point for in .
Definition: SplitKit.h:66
MachineBasicBlock * MBB
Definition: SplitKit.h:109
SplitEditor - Edit machine code and LiveIntervals for live range splitting.
Definition: SplitKit.h:241
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory)...
Definition: APInt.h:33
const LiveIntervals & LIS
Definition: SplitKit.h:87
int getNumber() const
MachineBasicBlocks are uniquely numbered at the function level, unless they&#39;re not in a MachineFuncti...
SlotIndex LastInstr
Last instr accessing current reg.
Definition: SplitKit.h:111
MachineBasicBlock::iterator getLastInsertPointIter(const LiveInterval &CurLI, MachineBasicBlock &MBB)
Returns the last insert point as an iterator for in .
Definition: SplitKit.cpp:139
TargetInstrInfo - Interface to description of machine instruction set.
const LiveInterval & getParent() const
getParent - Return the last analyzed interval.
Definition: SplitKit.h:173
MachineBasicBlock * getBlockNumbered(unsigned N) const
getBlockNumbered - MachineBasicBlocks are automatically numbered when they are inserted into the mach...
static GCRegistry::Add< OcamlGC > B("ocaml", "ocaml 3.10-compatible GC")
void dump(const SparseBitVector< ElementSize > &LHS, raw_ostream &out)
unsigned const MachineRegisterInfo * MRI
PointerIntPair - This class implements a pair of a pointer and small integer.
typename Sizer::Allocator Allocator
Definition: IntervalMap.h:959
SM_Partition(Default) - Try to create the complement interval so it doesn&#39;t overlap any other interva...
Definition: SplitKit.h:264
SM_Size - Overlap intervals to minimize the number of inserted COPY instructions. ...
Definition: SplitKit.h:271
unsigned currentIntv() const
currentIntv - Return the current interval index.
Definition: SplitKit.h:438
static const unsigned End
#define LLVM_LIBRARY_VISIBILITY
LLVM_LIBRARY_VISIBILITY - If a class marked with this attribute is linked into a shared library...
Definition: Compiler.h:105
const VirtRegMap & VRM
Definition: SplitKit.h:86
TargetRegisterInfo base class - We assume that the target defines a static array of TargetRegisterDes...
unsigned first
MachineBasicBlock::iterator getLastSplitPointIter(MachineBasicBlock *BB)
Definition: SplitKit.h:225
Basic Register Allocator
SmallPtrSet - This class implements a set which is optimized for holding SmallSize or less elements...
Definition: SmallPtrSet.h:418
static bool isSameInstr(SlotIndex A, SlotIndex B)
isSameInstr - Return true if A and B refer to the same instruction.
Definition: SlotIndexes.h:198
const MachineFunction & MF
Definition: SplitKit.h:85
SlotIndex FirstInstr
First instr accessing current reg.
Definition: SplitKit.h:110
This is a &#39;vector&#39; (really, a variable-sized array), optimized for the case when the array is small...
Definition: SmallVector.h:864
Additional information about basic blocks where the current variable is live.
Definition: SplitKit.h:108
SplitAnalysis - Analyze a LiveInterval, looking for live range splitting opportunities.
Definition: SplitKit.h:83
bool LiveOut
Current reg is live out.
Definition: SplitKit.h:114
static void clear(coro::Shape &Shape)
Definition: Coroutines.cpp:210
MachineRegisterInfo - Keep track of information for virtual and physical registers, including vreg register classes, use/def chains for registers, etc.
#define I(x, y, z)
Definition: MD5.cpp:58
bool didRepairRange() const
didRepairRange() - Returns true if CurLI was invalid and has been repaired by analyze().
Definition: SplitKit.h:166
ArrayRef< BlockInfo > getUseBlocks() const
getUseBlocks - Return an array of BlockInfo objects for the basic blocks where CurLI has uses...
Definition: SplitKit.h:188
bool isThroughBlock(unsigned MBB) const
isThroughBlock - Return true if CurLI is live through MBB without uses.
Definition: SplitKit.h:194
bool isOneInstr() const
isOneInstr - Returns true when this BlockInfo describes a single instruction.
Definition: SplitKit.h:118
unsigned getNumThroughBlocks() const
getNumThroughBlocks - Return the number of through blocks.
Definition: SplitKit.h:191
bool LiveIn
Current reg is live in.
Definition: SplitKit.h:113
SlotIndex - An opaque wrapper around machine indexes.
Definition: SlotIndexes.h:84
DominatorTree Class - Concrete subclass of DominatorTreeBase that is used to compute a normal dominat...