Coverage Report

Created: 2019-02-20 00:17

/Users/buildslave/jenkins/workspace/clang-stage2-coverage-R/llvm/include/llvm/CodeGen/LiveInterval.h
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//===- llvm/CodeGen/LiveInterval.h - Interval representation ----*- 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-exception
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//
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//===----------------------------------------------------------------------===//
8
//
9
// This file implements the LiveRange and LiveInterval classes.  Given some
10
// numbering of each the machine instructions an interval [i, j) is said to be a
11
// live range for register v if there is no instruction with number j' >= j
12
// such that v is live at j' and there is no instruction with number i' < i such
13
// that v is live at i'. In this implementation ranges can have holes,
14
// i.e. a range might look like [1,20), [50,65), [1000,1001).  Each
15
// individual segment is represented as an instance of LiveRange::Segment,
16
// and the whole range is represented as an instance of LiveRange.
17
//
18
//===----------------------------------------------------------------------===//
19
20
#ifndef LLVM_CODEGEN_LIVEINTERVAL_H
21
#define LLVM_CODEGEN_LIVEINTERVAL_H
22
23
#include "llvm/ADT/ArrayRef.h"
24
#include "llvm/ADT/IntEqClasses.h"
25
#include "llvm/ADT/STLExtras.h"
26
#include "llvm/ADT/SmallVector.h"
27
#include "llvm/ADT/iterator_range.h"
28
#include "llvm/CodeGen/SlotIndexes.h"
29
#include "llvm/MC/LaneBitmask.h"
30
#include "llvm/Support/Allocator.h"
31
#include "llvm/Support/MathExtras.h"
32
#include <algorithm>
33
#include <cassert>
34
#include <cstddef>
35
#include <functional>
36
#include <memory>
37
#include <set>
38
#include <tuple>
39
#include <utility>
40
41
namespace llvm {
42
43
  class CoalescerPair;
44
  class LiveIntervals;
45
  class MachineRegisterInfo;
46
  class raw_ostream;
47
48
  /// VNInfo - Value Number Information.
49
  /// This class holds information about a machine level values, including
50
  /// definition and use points.
51
  ///
52
  class VNInfo {
53
  public:
54
    using Allocator = BumpPtrAllocator;
55
56
    /// The ID number of this value.
57
    unsigned id;
58
59
    /// The index of the defining instruction.
60
    SlotIndex def;
61
62
    /// VNInfo constructor.
63
25.0M
    VNInfo(unsigned i, SlotIndex d) : id(i), def(d) {}
64
65
    /// VNInfo constructor, copies values from orig, except for the value number.
66
598k
    VNInfo(unsigned i, const VNInfo &orig) : id(i), def(orig.def) {}
67
68
    /// Copy from the parameter into this VNInfo.
69
11
    void copyFrom(VNInfo &src) {
70
11
      def = src.def;
71
11
    }
72
73
    /// Returns true if this value is defined by a PHI instruction (or was,
74
    /// PHI instructions may have been eliminated).
75
    /// PHI-defs begin at a block boundary, all other defs begin at register or
76
    /// EC slots.
77
59.2M
    bool isPHIDef() const { return def.isBlock(); }
78
79
    /// Returns true if this value is unused.
80
65.1M
    bool isUnused() const { return !def.isValid(); }
81
82
    /// Mark this value as unused.
83
120k
    void markUnused() { def = SlotIndex(); }
84
  };
85
86
  /// Result of a LiveRange query. This class hides the implementation details
87
  /// of live ranges, and it should be used as the primary interface for
88
  /// examining live ranges around instructions.
89
  class LiveQueryResult {
90
    VNInfo *const EarlyVal;
91
    VNInfo *const LateVal;
92
    const SlotIndex EndPoint;
93
    const bool Kill;
94
95
  public:
96
    LiveQueryResult(VNInfo *EarlyVal, VNInfo *LateVal, SlotIndex EndPoint,
97
                    bool Kill)
98
      : EarlyVal(EarlyVal), LateVal(LateVal), EndPoint(EndPoint), Kill(Kill)
99
48.1M
    {}
100
101
    /// Return the value that is live-in to the instruction. This is the value
102
    /// that will be read by the instruction's use operands. Return NULL if no
103
    /// value is live-in.
104
45.3M
    VNInfo *valueIn() const {
105
45.3M
      return EarlyVal;
106
45.3M
    }
107
108
    /// Return true if the live-in value is killed by this instruction. This
109
    /// means that either the live range ends at the instruction, or it changes
110
    /// value.
111
1.59M
    bool isKill() const {
112
1.59M
      return Kill;
113
1.59M
    }
114
115
    /// Return true if this instruction has a dead def.
116
2.72M
    bool isDeadDef() const {
117
2.72M
      return EndPoint.isDead();
118
2.72M
    }
119
120
    /// Return the value leaving the instruction, if any. This can be a
121
    /// live-through value, or a live def. A dead def returns NULL.
122
551k
    VNInfo *valueOut() const {
123
551k
      return isDeadDef() ? 
nullptr84
:
LateVal551k
;
124
551k
    }
125
126
    /// Returns the value alive at the end of the instruction, if any. This can
127
    /// be a live-through value, a live def or a dead def.
128
1.65M
    VNInfo *valueOutOrDead() const {
129
1.65M
      return LateVal;
130
1.65M
    }
131
132
    /// Return the value defined by this instruction, if any. This includes
133
    /// dead defs, it is the value created by the instruction's def operands.
134
24.0M
    VNInfo *valueDefined() const {
135
24.0M
      return EarlyVal == LateVal ? 
nullptr19.1M
:
LateVal4.85M
;
136
24.0M
    }
137
138
    /// Return the end point of the last live range segment to interact with
139
    /// the instruction, if any.
140
    ///
141
    /// The end point is an invalid SlotIndex only if the live range doesn't
142
    /// intersect the instruction at all.
143
    ///
144
    /// The end point may be at or past the end of the instruction's basic
145
    /// block. That means the value was live out of the block.
146
718k
    SlotIndex endPoint() const {
147
718k
      return EndPoint;
148
718k
    }
149
  };
150
151
  /// This class represents the liveness of a register, stack slot, etc.
152
  /// It manages an ordered list of Segment objects.
153
  /// The Segments are organized in a static single assignment form: At places
154
  /// where a new value is defined or different values reach a CFG join a new
155
  /// segment with a new value number is used.
156
  class LiveRange {
157
  public:
158
    /// This represents a simple continuous liveness interval for a value.
159
    /// The start point is inclusive, the end point exclusive. These intervals
160
    /// are rendered as [start,end).
161
    struct Segment {
162
      SlotIndex start;  // Start point of the interval (inclusive)
163
      SlotIndex end;    // End point of the interval (exclusive)
164
      VNInfo *valno = nullptr; // identifier for the value contained in this
165
                               // segment.
166
167
959k
      Segment() = default;
168
169
      Segment(SlotIndex S, SlotIndex E, VNInfo *V)
170
155M
        : start(S), end(E), valno(V) {
171
155M
        assert(S < E && "Cannot create empty or backwards segment");
172
155M
      }
173
174
      /// Return true if the index is covered by this segment.
175
170M
      bool contains(SlotIndex I) const {
176
170M
        return start <= I && 
I < end70.8k
;
177
170M
      }
178
179
      /// Return true if the given interval, [S, E), is covered by this segment.
180
0
      bool containsInterval(SlotIndex S, SlotIndex E) const {
181
0
        assert((S < E) && "Backwards interval?");
182
0
        return (start <= S && S < end) && (start < E && E <= end);
183
0
      }
184
185
68.2M
      bool operator<(const Segment &Other) const {
186
68.2M
        return std::tie(start, end) < std::tie(Other.start, Other.end);
187
68.2M
      }
188
0
      bool operator==(const Segment &Other) const {
189
0
        return start == Other.start && end == Other.end;
190
0
      }
191
192
      void dump() const;
193
    };
194
195
    using Segments = SmallVector<Segment, 2>;
196
    using VNInfoList = SmallVector<VNInfo *, 2>;
197
198
    Segments segments;   // the liveness segments
199
    VNInfoList valnos;   // value#'s
200
201
    // The segment set is used temporarily to accelerate initial computation
202
    // of live ranges of physical registers in computeRegUnitRange.
203
    // After that the set is flushed to the segment vector and deleted.
204
    using SegmentSet = std::set<Segment>;
205
    std::unique_ptr<SegmentSet> segmentSet;
206
207
    using iterator = Segments::iterator;
208
    using const_iterator = Segments::const_iterator;
209
210
323M
    iterator begin() { return segments.begin(); }
211
351M
    iterator end()   { return segments.end(); }
212
213
177M
    const_iterator begin() const { return segments.begin(); }
214
427M
    const_iterator end() const  { return segments.end(); }
215
216
    using vni_iterator = VNInfoList::iterator;
217
    using const_vni_iterator = VNInfoList::const_iterator;
218
219
911k
    vni_iterator vni_begin() { return valnos.begin(); }
220
911k
    vni_iterator vni_end()   { return valnos.end(); }
221
222
5.66M
    const_vni_iterator vni_begin() const { return valnos.begin(); }
223
5.66M
    const_vni_iterator vni_end() const   { return valnos.end(); }
224
225
    /// Constructs a new LiveRange object.
226
    LiveRange(bool UseSegmentSet = false)
227
        : segmentSet(UseSegmentSet ? llvm::make_unique<SegmentSet>()
228
19.0M
                                   : nullptr) {}
229
230
    /// Constructs a new LiveRange object by copying segments and valnos from
231
    /// another LiveRange.
232
379k
    LiveRange(const LiveRange &Other, BumpPtrAllocator &Allocator) {
233
379k
      assert(Other.segmentSet == nullptr &&
234
379k
             "Copying of LiveRanges with active SegmentSets is not supported");
235
379k
      assign(Other, Allocator);
236
379k
    }
237
238
    /// Copies values numbers and live segments from \p Other into this range.
239
520k
    void assign(const LiveRange &Other, BumpPtrAllocator &Allocator) {
240
520k
      if (this == &Other)
241
0
        return;
242
520k
243
520k
      assert(Other.segmentSet == nullptr &&
244
520k
             "Copying of LiveRanges with active SegmentSets is not supported");
245
520k
      // Duplicate valnos.
246
520k
      for (const VNInfo *VNI : Other.valnos)
247
598k
        createValueCopy(VNI, Allocator);
248
520k
      // Now we can copy segments and remap their valnos.
249
520k
      for (const Segment &S : Other.segments)
250
807k
        segments.push_back(Segment(S.start, S.end, valnos[S.valno->id]));
251
520k
    }
252
253
    /// advanceTo - Advance the specified iterator to point to the Segment
254
    /// containing the specified position, or end() if the position is past the
255
    /// end of the range.  If no Segment contains this position, but the
256
    /// position is in a hole, this method returns an iterator pointing to the
257
    /// Segment immediately after the hole.
258
17.6M
    iterator advanceTo(iterator I, SlotIndex Pos) {
259
17.6M
      assert(I != end());
260
17.6M
      if (Pos >= endIndex())
261
5.27M
        return end();
262
38.7M
      
while (12.3M
I->end <= Pos)
++I26.3M
;
263
12.3M
      return I;
264
12.3M
    }
265
266
221M
    const_iterator advanceTo(const_iterator I, SlotIndex Pos) const {
267
221M
      assert(I != end());
268
221M
      if (Pos >= endIndex())
269
10.5M
        return end();
270
259M
      
while (211M
I->end <= Pos)
++I47.9M
;
271
211M
      return I;
272
211M
    }
273
274
    /// find - Return an iterator pointing to the first segment that ends after
275
    /// Pos, or end(). This is the same as advanceTo(begin(), Pos), but faster
276
    /// when searching large ranges.
277
    ///
278
    /// If Pos is contained in a Segment, that segment is returned.
279
    /// If Pos is in a hole, the following Segment is returned.
280
    /// If Pos is beyond endIndex, end() is returned.
281
    iterator find(SlotIndex Pos);
282
283
166M
    const_iterator find(SlotIndex Pos) const {
284
166M
      return const_cast<LiveRange*>(this)->find(Pos);
285
166M
    }
286
287
658k
    void clear() {
288
658k
      valnos.clear();
289
658k
      segments.clear();
290
658k
    }
291
292
180M
    size_t size() const {
293
180M
      return segments.size();
294
180M
    }
295
296
52
    bool hasAtLeastOneValue() const { return !valnos.empty(); }
297
298
319k
    bool containsOneValue() const { return valnos.size() == 1; }
299
300
63.5M
    unsigned getNumValNums() const { return (unsigned)valnos.size(); }
301
302
    /// getValNumInfo - Returns pointer to the specified val#.
303
    ///
304
84.7M
    inline VNInfo *getValNumInfo(unsigned ValNo) {
305
84.7M
      return valnos[ValNo];
306
84.7M
    }
307
4.44M
    inline const VNInfo *getValNumInfo(unsigned ValNo) const {
308
4.44M
      return valnos[ValNo];
309
4.44M
    }
310
311
    /// containsValue - Returns true if VNI belongs to this range.
312
    bool containsValue(const VNInfo *VNI) const {
313
      return VNI && VNI->id < getNumValNums() && VNI == getValNumInfo(VNI->id);
314
    }
315
316
    /// getNextValue - Create a new value number and return it.  MIIdx specifies
317
    /// the instruction that defines the value number.
318
24.9M
    VNInfo *getNextValue(SlotIndex def, VNInfo::Allocator &VNInfoAllocator) {
319
24.9M
      VNInfo *VNI =
320
24.9M
        new (VNInfoAllocator) VNInfo((unsigned)valnos.size(), def);
321
24.9M
      valnos.push_back(VNI);
322
24.9M
      return VNI;
323
24.9M
    }
324
325
    /// createDeadDef - Make sure the range has a value defined at Def.
326
    /// If one already exists, return it. Otherwise allocate a new value and
327
    /// add liveness for a dead def.
328
    VNInfo *createDeadDef(SlotIndex Def, VNInfo::Allocator &VNIAlloc);
329
330
    /// Create a def of value @p VNI. Return @p VNI. If there already exists
331
    /// a definition at VNI->def, the value defined there must be @p VNI.
332
    VNInfo *createDeadDef(VNInfo *VNI);
333
334
    /// Create a copy of the given value. The new value will be identical except
335
    /// for the Value number.
336
    VNInfo *createValueCopy(const VNInfo *orig,
337
598k
                            VNInfo::Allocator &VNInfoAllocator) {
338
598k
      VNInfo *VNI =
339
598k
        new (VNInfoAllocator) VNInfo((unsigned)valnos.size(), *orig);
340
598k
      valnos.push_back(VNI);
341
598k
      return VNI;
342
598k
    }
343
344
    /// RenumberValues - Renumber all values in order of appearance and remove
345
    /// unused values.
346
    void RenumberValues();
347
348
    /// MergeValueNumberInto - This method is called when two value numbers
349
    /// are found to be equivalent.  This eliminates V1, replacing all
350
    /// segments with the V1 value number with the V2 value number.  This can
351
    /// cause merging of V1/V2 values numbers and compaction of the value space.
352
    VNInfo* MergeValueNumberInto(VNInfo *V1, VNInfo *V2);
353
354
    /// Merge all of the live segments of a specific val# in RHS into this live
355
    /// range as the specified value number. The segments in RHS are allowed
356
    /// to overlap with segments in the current range, it will replace the
357
    /// value numbers of the overlaped live segments with the specified value
358
    /// number.
359
    void MergeSegmentsInAsValue(const LiveRange &RHS, VNInfo *LHSValNo);
360
361
    /// MergeValueInAsValue - Merge all of the segments of a specific val#
362
    /// in RHS into this live range as the specified value number.
363
    /// The segments in RHS are allowed to overlap with segments in the
364
    /// current range, but only if the overlapping segments have the
365
    /// specified value number.
366
    void MergeValueInAsValue(const LiveRange &RHS,
367
                             const VNInfo *RHSValNo, VNInfo *LHSValNo);
368
369
664M
    bool empty() const { return segments.empty(); }
370
371
    /// beginIndex - Return the lowest numbered slot covered.
372
64.6M
    SlotIndex beginIndex() const {
373
64.6M
      assert(!empty() && "Call to beginIndex() on empty range.");
374
64.6M
      return segments.front().start;
375
64.6M
    }
376
377
    /// endNumber - return the maximum point of the range of the whole,
378
    /// exclusive.
379
484M
    SlotIndex endIndex() const {
380
484M
      assert(!empty() && "Call to endIndex() on empty range.");
381
484M
      return segments.back().end;
382
484M
    }
383
384
132
    bool expiredAt(SlotIndex index) const {
385
132
      return index >= endIndex();
386
132
    }
387
388
39.6M
    bool liveAt(SlotIndex index) const {
389
39.6M
      const_iterator r = find(index);
390
39.6M
      return r != end() && 
r->start <= index35.3M
;
391
39.6M
    }
392
393
    /// Return the segment that contains the specified index, or null if there
394
    /// is none.
395
18.8M
    const Segment *getSegmentContaining(SlotIndex Idx) const {
396
18.8M
      const_iterator I = FindSegmentContaining(Idx);
397
18.8M
      return I == end() ? 
nullptr4.33M
:
&*I14.5M
;
398
18.8M
    }
399
400
    /// Return the live segment that contains the specified index, or null if
401
    /// there is none.
402
13.1k
    Segment *getSegmentContaining(SlotIndex Idx) {
403
13.1k
      iterator I = FindSegmentContaining(Idx);
404
13.1k
      return I == end() ? 
nullptr718
:
&*I12.4k
;
405
13.1k
    }
406
407
    /// getVNInfoAt - Return the VNInfo that is live at Idx, or NULL.
408
15.1M
    VNInfo *getVNInfoAt(SlotIndex Idx) const {
409
15.1M
      const_iterator I = FindSegmentContaining(Idx);
410
15.1M
      return I == end() ? 
nullptr273k
:
I->valno14.8M
;
411
15.1M
    }
412
413
    /// getVNInfoBefore - Return the VNInfo that is live up to but not
414
    /// necessarilly including Idx, or NULL. Use this to find the reaching def
415
    /// used by an instruction at this SlotIndex position.
416
17.7M
    VNInfo *getVNInfoBefore(SlotIndex Idx) const {
417
17.7M
      const_iterator I = FindSegmentContaining(Idx.getPrevSlot());
418
17.7M
      return I == end() ? 
nullptr2.70M
:
I->valno15.0M
;
419
17.7M
    }
420
421
    /// Return an iterator to the segment that contains the specified index, or
422
    /// end() if there is none.
423
16.6M
    iterator FindSegmentContaining(SlotIndex Idx) {
424
16.6M
      iterator I = find(Idx);
425
16.6M
      return I != end() && 
I->start <= Idx16.6M
?
I16.6M
:
end()3.97k
;
426
16.6M
    }
427
428
51.7M
    const_iterator FindSegmentContaining(SlotIndex Idx) const {
429
51.7M
      const_iterator I = find(Idx);
430
51.7M
      return I != end() && 
I->start <= Idx47.6M
?
I44.4M
:
end()7.31M
;
431
51.7M
    }
432
433
    /// overlaps - Return true if the intersection of the two live ranges is
434
    /// not empty.
435
7.32M
    bool overlaps(const LiveRange &other) const {
436
7.32M
      if (other.empty())
437
4.52k
        return false;
438
7.31M
      return overlapsFrom(other, other.begin());
439
7.31M
    }
440
441
    /// overlaps - Return true if the two ranges have overlapping segments
442
    /// that are not coalescable according to CP.
443
    ///
444
    /// Overlapping segments where one range is defined by a coalescable
445
    /// copy are allowed.
446
    bool overlaps(const LiveRange &Other, const CoalescerPair &CP,
447
                  const SlotIndexes&) const;
448
449
    /// overlaps - Return true if the live range overlaps an interval specified
450
    /// by [Start, End).
451
    bool overlaps(SlotIndex Start, SlotIndex End) const;
452
453
    /// overlapsFrom - Return true if the intersection of the two live ranges
454
    /// is not empty.  The specified iterator is a hint that we can begin
455
    /// scanning the Other range starting at I.
456
    bool overlapsFrom(const LiveRange &Other, const_iterator StartPos) const;
457
458
    /// Returns true if all segments of the @p Other live range are completely
459
    /// covered by this live range.
460
    /// Adjacent live ranges do not affect the covering:the liverange
461
    /// [1,5](5,10] covers (3,7].
462
    bool covers(const LiveRange &Other) const;
463
464
    /// Add the specified Segment to this range, merging segments as
465
    /// appropriate.  This returns an iterator to the inserted segment (which
466
    /// may have grown since it was inserted).
467
    iterator addSegment(Segment S);
468
469
    /// Attempt to extend a value defined after @p StartIdx to include @p Use.
470
    /// Both @p StartIdx and @p Use should be in the same basic block. In case
471
    /// of subranges, an extension could be prevented by an explicit "undef"
472
    /// caused by a <def,read-undef> on a non-overlapping lane. The list of
473
    /// location of such "undefs" should be provided in @p Undefs.
474
    /// The return value is a pair: the first element is VNInfo of the value
475
    /// that was extended (possibly nullptr), the second is a boolean value
476
    /// indicating whether an "undef" was encountered.
477
    /// If this range is live before @p Use in the basic block that starts at
478
    /// @p StartIdx, and there is no intervening "undef", extend it to be live
479
    /// up to @p Use, and return the pair {value, false}. If there is no
480
    /// segment before @p Use and there is no "undef" between @p StartIdx and
481
    /// @p Use, return {nullptr, false}. If there is an "undef" before @p Use,
482
    /// return {nullptr, true}.
483
    std::pair<VNInfo*,bool> extendInBlock(ArrayRef<SlotIndex> Undefs,
484
        SlotIndex StartIdx, SlotIndex Kill);
485
486
    /// Simplified version of the above "extendInBlock", which assumes that
487
    /// no register lanes are undefined by <def,read-undef> operands.
488
    /// If this range is live before @p Use in the basic block that starts
489
    /// at @p StartIdx, extend it to be live up to @p Use, and return the
490
    /// value. If there is no segment before @p Use, return nullptr.
491
    VNInfo *extendInBlock(SlotIndex StartIdx, SlotIndex Kill);
492
493
    /// join - Join two live ranges (this, and other) together.  This applies
494
    /// mappings to the value numbers in the LHS/RHS ranges as specified.  If
495
    /// the ranges are not joinable, this aborts.
496
    void join(LiveRange &Other,
497
              const int *ValNoAssignments,
498
              const int *RHSValNoAssignments,
499
              SmallVectorImpl<VNInfo *> &NewVNInfo);
500
501
    /// True iff this segment is a single segment that lies between the
502
    /// specified boundaries, exclusively. Vregs live across a backedge are not
503
    /// considered local. The boundaries are expected to lie within an extended
504
    /// basic block, so vregs that are not live out should contain no holes.
505
326k
    bool isLocal(SlotIndex Start, SlotIndex End) const {
506
326k
      return beginIndex() > Start.getBaseIndex() &&
507
326k
        
endIndex() < End.getBoundaryIndex()179k
;
508
326k
    }
509
510
    /// Remove the specified segment from this range.  Note that the segment
511
    /// must be a single Segment in its entirety.
512
    void removeSegment(SlotIndex Start, SlotIndex End,
513
                       bool RemoveDeadValNo = false);
514
515
896
    void removeSegment(Segment S, bool RemoveDeadValNo = false) {
516
896
      removeSegment(S.start, S.end, RemoveDeadValNo);
517
896
    }
518
519
    /// Remove segment pointed to by iterator @p I from this range.  This does
520
    /// not remove dead value numbers.
521
8.66k
    iterator removeSegment(iterator I) {
522
8.66k
      return segments.erase(I);
523
8.66k
    }
524
525
    /// Query Liveness at Idx.
526
    /// The sub-instruction slot of Idx doesn't matter, only the instruction
527
    /// it refers to is considered.
528
48.1M
    LiveQueryResult Query(SlotIndex Idx) const {
529
48.1M
      // Find the segment that enters the instruction.
530
48.1M
      const_iterator I = find(Idx.getBaseIndex());
531
48.1M
      const_iterator E = end();
532
48.1M
      if (I == E)
533
4.84M
        return LiveQueryResult(nullptr, nullptr, SlotIndex(), false);
534
43.3M
535
43.3M
      // Is this an instruction live-in segment?
536
43.3M
      // If Idx is the start index of a basic block, include live-in segments
537
43.3M
      // that start at Idx.getBaseIndex().
538
43.3M
      VNInfo *EarlyVal = nullptr;
539
43.3M
      VNInfo *LateVal  = nullptr;
540
43.3M
      SlotIndex EndPoint;
541
43.3M
      bool Kill = false;
542
43.3M
      if (I->start <= Idx.getBaseIndex()) {
543
30.2M
        EarlyVal = I->valno;
544
30.2M
        EndPoint = I->end;
545
30.2M
        // Move to the potentially live-out segment.
546
30.2M
        if (SlotIndex::isSameInstr(Idx, I->end)) {
547
18.9M
          Kill = true;
548
18.9M
          if (++I == E)
549
14.3M
            return LiveQueryResult(EarlyVal, LateVal, EndPoint, Kill);
550
15.9M
        }
551
15.9M
        // Special case: A PHIDef value can have its def in the middle of a
552
15.9M
        // segment if the value happens to be live out of the layout
553
15.9M
        // predecessor.
554
15.9M
        // Such a value is not live-in.
555
15.9M
        if (EarlyVal->def == Idx.getBaseIndex())
556
41.8k
          EarlyVal = nullptr;
557
15.9M
      }
558
43.3M
      // I now points to the segment that may be live-through, or defined by
559
43.3M
      // this instr. Ignore segments starting after the current instr.
560
43.3M
      
if (28.9M
!SlotIndex::isEarlierInstr(Idx, I->start)28.9M
) {
561
15.9M
        LateVal = I->valno;
562
15.9M
        EndPoint = I->end;
563
15.9M
      }
564
28.9M
      return LiveQueryResult(EarlyVal, LateVal, EndPoint, Kill);
565
43.3M
    }
566
567
    /// removeValNo - Remove all the segments defined by the specified value#.
568
    /// Also remove the value# from value# list.
569
    void removeValNo(VNInfo *ValNo);
570
571
    /// Returns true if the live range is zero length, i.e. no live segments
572
    /// span instructions. It doesn't pay to spill such a range.
573
8.51M
    bool isZeroLength(SlotIndexes *Indexes) const {
574
8.51M
      for (const Segment &S : segments)
575
8.74M
        if (Indexes->getNextNonNullIndex(S.start).getBaseIndex() <
576
8.74M
            S.end.getBaseIndex())
577
5.66M
          return false;
578
8.51M
      
return true2.85M
;
579
8.51M
    }
580
581
    // Returns true if any segment in the live range contains any of the
582
    // provided slot indexes.  Slots which occur in holes between
583
    // segments will not cause the function to return true.
584
    bool isLiveAtIndexes(ArrayRef<SlotIndex> Slots) const;
585
586
0
    bool operator<(const LiveRange& other) const {
587
0
      const SlotIndex &thisIndex = beginIndex();
588
0
      const SlotIndex &otherIndex = other.beginIndex();
589
0
      return thisIndex < otherIndex;
590
0
    }
591
592
    /// Returns true if there is an explicit "undef" between @p Begin
593
    /// @p End.
594
    bool isUndefIn(ArrayRef<SlotIndex> Undefs, SlotIndex Begin,
595
56.6M
                   SlotIndex End) const {
596
56.6M
      return std::any_of(Undefs.begin(), Undefs.end(),
597
56.6M
                [Begin,End] (SlotIndex Idx) -> bool {
598
293k
                  return Begin <= Idx && 
Idx < End203
;
599
293k
                });
600
56.6M
    }
601
602
    /// Flush segment set into the regular segment vector.
603
    /// The method is to be called after the live range
604
    /// has been created, if use of the segment set was
605
    /// activated in the constructor of the live range.
606
    void flushSegmentSet();
607
608
    void print(raw_ostream &OS) const;
609
    void dump() const;
610
611
    /// Walk the range and assert if any invariants fail to hold.
612
    ///
613
    /// Note that this is a no-op when asserts are disabled.
614
#ifdef NDEBUG
615
20.4M
    void verify() const {}
616
#else
617
    void verify() const;
618
#endif
619
620
  protected:
621
    /// Append a segment to the list of segments.
622
    void append(const LiveRange::Segment S);
623
624
  private:
625
    friend class LiveRangeUpdater;
626
    void addSegmentToSet(Segment S);
627
    void markValNoForDeletion(VNInfo *V);
628
  };
629
630
9
  inline raw_ostream &operator<<(raw_ostream &OS, const LiveRange &LR) {
631
9
    LR.print(OS);
632
9
    return OS;
633
9
  }
634
635
  /// LiveInterval - This class represents the liveness of a register,
636
  /// or stack slot.
637
  class LiveInterval : public LiveRange {
638
  public:
639
    using super = LiveRange;
640
641
    /// A live range for subregisters. The LaneMask specifies which parts of the
642
    /// super register are covered by the interval.
643
    /// (@sa TargetRegisterInfo::getSubRegIndexLaneMask()).
644
    class SubRange : public LiveRange {
645
    public:
646
      SubRange *Next = nullptr;
647
      LaneBitmask LaneMask;
648
649
      /// Constructs a new SubRange object.
650
156k
      SubRange(LaneBitmask LaneMask) : LaneMask(LaneMask) {}
651
652
      /// Constructs a new SubRange object by copying liveness from @p Other.
653
      SubRange(LaneBitmask LaneMask, const LiveRange &Other,
654
               BumpPtrAllocator &Allocator)
655
188k
        : LiveRange(Other, Allocator), LaneMask(LaneMask) {}
656
657
      void print(raw_ostream &OS) const;
658
      void dump() const;
659
    };
660
661
  private:
662
    SubRange *SubRanges = nullptr; ///< Single linked list of subregister live
663
                                   /// ranges.
664
665
  public:
666
    const unsigned reg;  // the register or stack slot of this interval.
667
    float weight;        // weight of this interval
668
669
13.9M
    LiveInterval(unsigned Reg, float Weight) : reg(Reg), weight(Weight) {}
670
671
13.9M
    ~LiveInterval() {
672
13.9M
      clearSubRanges();
673
13.9M
    }
674
675
    template<typename T>
676
    class SingleLinkedListIterator {
677
      T *P;
678
679
    public:
680
31.4M
      SingleLinkedListIterator<T>(T *P) : P(P) {}
llvm::LiveInterval::SingleLinkedListIterator<llvm::LiveInterval::SubRange const>::SingleLinkedListIterator(llvm::LiveInterval::SubRange const*)
Line
Count
Source
680
20.3M
      SingleLinkedListIterator<T>(T *P) : P(P) {}
llvm::LiveInterval::SingleLinkedListIterator<llvm::LiveInterval::SubRange>::SingleLinkedListIterator(llvm::LiveInterval::SubRange*)
Line
Count
Source
680
11.0M
      SingleLinkedListIterator<T>(T *P) : P(P) {}
681
682
37.1M
      SingleLinkedListIterator<T> &operator++() {
683
37.1M
        P = P->Next;
684
37.1M
        return *this;
685
37.1M
      }
llvm::LiveInterval::SingleLinkedListIterator<llvm::LiveInterval::SubRange const>::operator++()
Line
Count
Source
682
30.9M
      SingleLinkedListIterator<T> &operator++() {
683
30.9M
        P = P->Next;
684
30.9M
        return *this;
685
30.9M
      }
llvm::LiveInterval::SingleLinkedListIterator<llvm::LiveInterval::SubRange>::operator++()
Line
Count
Source
682
6.21M
      SingleLinkedListIterator<T> &operator++() {
683
6.21M
        P = P->Next;
684
6.21M
        return *this;
685
6.21M
      }
686
      SingleLinkedListIterator<T> operator++(int) {
687
        SingleLinkedListIterator res = *this;
688
        ++*this;
689
        return res;
690
      }
691
52.8M
      bool operator!=(const SingleLinkedListIterator<T> &Other) {
692
52.8M
        return P != Other.operator->();
693
52.8M
      }
llvm::LiveInterval::SingleLinkedListIterator<llvm::LiveInterval::SubRange const>::operator!=(llvm::LiveInterval::SingleLinkedListIterator<llvm::LiveInterval::SubRange const> const&)
Line
Count
Source
691
41.1M
      bool operator!=(const SingleLinkedListIterator<T> &Other) {
692
41.1M
        return P != Other.operator->();
693
41.1M
      }
llvm::LiveInterval::SingleLinkedListIterator<llvm::LiveInterval::SubRange>::operator!=(llvm::LiveInterval::SingleLinkedListIterator<llvm::LiveInterval::SubRange> const&)
Line
Count
Source
691
11.7M
      bool operator!=(const SingleLinkedListIterator<T> &Other) {
692
11.7M
        return P != Other.operator->();
693
11.7M
      }
694
      bool operator==(const SingleLinkedListIterator<T> &Other) {
695
        return P == Other.operator->();
696
      }
697
40.1M
      T &operator*() const {
698
40.1M
        return *P;
699
40.1M
      }
llvm::LiveInterval::SingleLinkedListIterator<llvm::LiveInterval::SubRange const>::operator*() const
Line
Count
Source
697
31.7M
      T &operator*() const {
698
31.7M
        return *P;
699
31.7M
      }
llvm::LiveInterval::SingleLinkedListIterator<llvm::LiveInterval::SubRange>::operator*() const
Line
Count
Source
697
8.44M
      T &operator*() const {
698
8.44M
        return *P;
699
8.44M
      }
700
52.8M
      T *operator->() const {
701
52.8M
        return P;
702
52.8M
      }
llvm::LiveInterval::SingleLinkedListIterator<llvm::LiveInterval::SubRange const>::operator->() const
Line
Count
Source
700
41.1M
      T *operator->() const {
701
41.1M
        return P;
702
41.1M
      }
llvm::LiveInterval::SingleLinkedListIterator<llvm::LiveInterval::SubRange>::operator->() const
Line
Count
Source
700
11.7M
      T *operator->() const {
701
11.7M
        return P;
702
11.7M
      }
703
    };
704
705
    using subrange_iterator = SingleLinkedListIterator<SubRange>;
706
    using const_subrange_iterator = SingleLinkedListIterator<const SubRange>;
707
708
5.54M
    subrange_iterator subrange_begin() {
709
5.54M
      return subrange_iterator(SubRanges);
710
5.54M
    }
711
5.54M
    subrange_iterator subrange_end() {
712
5.54M
      return subrange_iterator(nullptr);
713
5.54M
    }
714
715
10.1M
    const_subrange_iterator subrange_begin() const {
716
10.1M
      return const_subrange_iterator(SubRanges);
717
10.1M
    }
718
10.1M
    const_subrange_iterator subrange_end() const {
719
10.1M
      return const_subrange_iterator(nullptr);
720
10.1M
    }
721
722
5.54M
    iterator_range<subrange_iterator> subranges() {
723
5.54M
      return make_range(subrange_begin(), subrange_end());
724
5.54M
    }
725
726
10.1M
    iterator_range<const_subrange_iterator> subranges() const {
727
10.1M
      return make_range(subrange_begin(), subrange_end());
728
10.1M
    }
729
730
    /// Creates a new empty subregister live range. The range is added at the
731
    /// beginning of the subrange list; subrange iterators stay valid.
732
    SubRange *createSubRange(BumpPtrAllocator &Allocator,
733
156k
                             LaneBitmask LaneMask) {
734
156k
      SubRange *Range = new (Allocator) SubRange(LaneMask);
735
156k
      appendSubRange(Range);
736
156k
      return Range;
737
156k
    }
738
739
    /// Like createSubRange() but the new range is filled with a copy of the
740
    /// liveness information in @p CopyFrom.
741
    SubRange *createSubRangeFrom(BumpPtrAllocator &Allocator,
742
                                 LaneBitmask LaneMask,
743
188k
                                 const LiveRange &CopyFrom) {
744
188k
      SubRange *Range = new (Allocator) SubRange(LaneMask, CopyFrom, Allocator);
745
188k
      appendSubRange(Range);
746
188k
      return Range;
747
188k
    }
748
749
    /// Returns true if subregister liveness information is available.
750
231M
    bool hasSubRanges() const {
751
231M
      return SubRanges != nullptr;
752
231M
    }
753
754
    /// Removes all subregister liveness information.
755
    void clearSubRanges();
756
757
    /// Removes all subranges without any segments (subranges without segments
758
    /// are not considered valid and should only exist temporarily).
759
    void removeEmptySubRanges();
760
761
    /// getSize - Returns the sum of sizes of all the LiveRange's.
762
    ///
763
    unsigned getSize() const;
764
765
    /// isSpillable - Can this interval be spilled?
766
25.0M
    bool isSpillable() const {
767
25.0M
      return weight != huge_valf;
768
25.0M
    }
769
770
    /// markNotSpillable - Mark interval as not spillable
771
2.85M
    void markNotSpillable() {
772
2.85M
      weight = huge_valf;
773
2.85M
    }
774
775
    /// For a given lane mask @p LaneMask, compute indexes at which the
776
    /// lane is marked undefined by subregister <def,read-undef> definitions.
777
    void computeSubRangeUndefs(SmallVectorImpl<SlotIndex> &Undefs,
778
                               LaneBitmask LaneMask,
779
                               const MachineRegisterInfo &MRI,
780
                               const SlotIndexes &Indexes) const;
781
782
    /// Refines the subranges to support \p LaneMask. This may only be called
783
    /// for LI.hasSubrange()==true. Subregister ranges are split or created
784
    /// until \p LaneMask can be matched exactly. \p Mod is executed on the
785
    /// matching subranges.
786
    ///
787
    /// Example:
788
    ///    Given an interval with subranges with lanemasks L0F00, L00F0 and
789
    ///    L000F, refining for mask L0018. Will split the L00F0 lane into
790
    ///    L00E0 and L0010 and the L000F lane into L0007 and L0008. The Mod
791
    ///    function will be applied to the L0010 and L0008 subranges.
792
    void refineSubRanges(BumpPtrAllocator &Allocator, LaneBitmask LaneMask,
793
                         std::function<void(LiveInterval::SubRange&)> Apply);
794
795
18.8k
    bool operator<(const LiveInterval& other) const {
796
18.8k
      const SlotIndex &thisIndex = beginIndex();
797
18.8k
      const SlotIndex &otherIndex = other.beginIndex();
798
18.8k
      return std::tie(thisIndex, reg) < std::tie(otherIndex, other.reg);
799
18.8k
    }
800
801
    void print(raw_ostream &OS) const;
802
    void dump() const;
803
804
    /// Walks the interval and assert if any invariants fail to hold.
805
    ///
806
    /// Note that this is a no-op when asserts are disabled.
807
#ifdef NDEBUG
808
1.36k
    void verify(const MachineRegisterInfo *MRI = nullptr) const {}
809
#else
810
    void verify(const MachineRegisterInfo *MRI = nullptr) const;
811
#endif
812
813
  private:
814
    /// Appends @p Range to SubRanges list.
815
344k
    void appendSubRange(SubRange *Range) {
816
344k
      Range->Next = SubRanges;
817
344k
      SubRanges = Range;
818
344k
    }
819
820
    /// Free memory held by SubRange.
821
    void freeSubRange(SubRange *S);
822
  };
823
824
  inline raw_ostream &operator<<(raw_ostream &OS,
825
4
                                 const LiveInterval::SubRange &SR) {
826
4
    SR.print(OS);
827
4
    return OS;
828
4
  }
829
830
6
  inline raw_ostream &operator<<(raw_ostream &OS, const LiveInterval &LI) {
831
6
    LI.print(OS);
832
6
    return OS;
833
6
  }
834
835
  raw_ostream &operator<<(raw_ostream &OS, const LiveRange::Segment &S);
836
837
180M
  inline bool operator<(SlotIndex V, const LiveRange::Segment &S) {
838
180M
    return V < S.start;
839
180M
  }
840
841
680k
  inline bool operator<(const LiveRange::Segment &S, SlotIndex V) {
842
680k
    return S.start < V;
843
680k
  }
844
845
  /// Helper class for performant LiveRange bulk updates.
846
  ///
847
  /// Calling LiveRange::addSegment() repeatedly can be expensive on large
848
  /// live ranges because segments after the insertion point may need to be
849
  /// shifted. The LiveRangeUpdater class can defer the shifting when adding
850
  /// many segments in order.
851
  ///
852
  /// The LiveRange will be in an invalid state until flush() is called.
853
  class LiveRangeUpdater {
854
    LiveRange *LR;
855
    SlotIndex LastStart;
856
    LiveRange::iterator WriteI;
857
    LiveRange::iterator ReadI;
858
    SmallVector<LiveRange::Segment, 16> Spills;
859
    void mergeSpills();
860
861
  public:
862
    /// Create a LiveRangeUpdater for adding segments to LR.
863
    /// LR will temporarily be in an invalid state until flush() is called.
864
8.93M
    LiveRangeUpdater(LiveRange *lr = nullptr) : LR(lr) {}
865
866
8.93M
    ~LiveRangeUpdater() { flush(); }
867
868
    /// Add a segment to LR and coalesce when possible, just like
869
    /// LR.addSegment(). Segments should be added in increasing start order for
870
    /// best performance.
871
    void add(LiveRange::Segment);
872
873
30.9M
    void add(SlotIndex Start, SlotIndex End, VNInfo *VNI) {
874
30.9M
      add(LiveRange::Segment(Start, End, VNI));
875
30.9M
    }
876
877
    /// Return true if the LR is currently in an invalid state, and flush()
878
    /// needs to be called.
879
21.3M
    bool isDirty() const { return LastStart.isValid(); }
880
881
    /// Flush the updater state to LR so it is valid and contains all added
882
    /// segments.
883
    void flush();
884
885
    /// Select a different destination live range.
886
1.44M
    void setDest(LiveRange *lr) {
887
1.44M
      if (LR != lr && 
isDirty()83.7k
)
888
458
        flush();
889
1.44M
      LR = lr;
890
1.44M
    }
891
892
    /// Get the current destination live range.
893
    LiveRange *getDest() const { return LR; }
894
895
    void dump() const;
896
    void print(raw_ostream&) const;
897
  };
898
899
0
  inline raw_ostream &operator<<(raw_ostream &OS, const LiveRangeUpdater &X) {
900
0
    X.print(OS);
901
0
    return OS;
902
0
  }
903
904
  /// ConnectedVNInfoEqClasses - Helper class that can divide VNInfos in a
905
  /// LiveInterval into equivalence clases of connected components. A
906
  /// LiveInterval that has multiple connected components can be broken into
907
  /// multiple LiveIntervals.
908
  ///
909
  /// Given a LiveInterval that may have multiple connected components, run:
910
  ///
911
  ///   unsigned numComps = ConEQ.Classify(LI);
912
  ///   if (numComps > 1) {
913
  ///     // allocate numComps-1 new LiveIntervals into LIS[1..]
914
  ///     ConEQ.Distribute(LIS);
915
  /// }
916
917
  class ConnectedVNInfoEqClasses {
918
    LiveIntervals &LIS;
919
    IntEqClasses EqClass;
920
921
  public:
922
2.65M
    explicit ConnectedVNInfoEqClasses(LiveIntervals &lis) : LIS(lis) {}
923
924
    /// Classify the values in \p LR into connected components.
925
    /// Returns the number of connected components.
926
    unsigned Classify(const LiveRange &LR);
927
928
    /// getEqClass - Classify creates equivalence classes numbered 0..N. Return
929
    /// the equivalence class assigned the VNI.
930
815k
    unsigned getEqClass(const VNInfo *VNI) const { return EqClass[VNI->id]; }
931
932
    /// Distribute values in \p LI into a separate LiveIntervals
933
    /// for each connected component. LIV must have an empty LiveInterval for
934
    /// each additional connected component. The first connected component is
935
    /// left in \p LI.
936
    void Distribute(LiveInterval &LI, LiveInterval *LIV[],
937
                    MachineRegisterInfo &MRI);
938
  };
939
940
} // end namespace llvm
941
942
#endif // LLVM_CODEGEN_LIVEINTERVAL_H