1 //===-- llvm/CodeGen/LiveInterval.h - Interval representation ---*- 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 implements the LiveRange and LiveInterval classes. Given some 11 // numbering of each the machine instructions an interval [i, j) is said to be a 12 // live interval for register v if there is no instruction with number j' >= j 13 // such that v is live at j' and there is no instruction with number i' < i such 14 // that v is live at i'. In this implementation intervals can have holes, 15 // i.e. an interval might look like [1,20), [50,65), [1000,1001). Each 16 // individual range is represented as an instance of LiveRange, and the whole 17 // interval is represented as an instance of LiveInterval. 18 // 19 //===----------------------------------------------------------------------===// 20 21 #ifndef LLVM_CODEGEN_LIVEINTERVAL_H 22 #define LLVM_CODEGEN_LIVEINTERVAL_H 23 24 #include "llvm/ADT/IntEqClasses.h" 25 #include "llvm/CodeGen/SlotIndexes.h" 26 #include "llvm/Support/AlignOf.h" 27 #include "llvm/Support/Allocator.h" 28 #include <cassert> 29 #include <climits> 30 31 namespace llvm { 32 class CoalescerPair; 33 class LiveIntervals; 34 class MachineInstr; 35 class MachineRegisterInfo; 36 class TargetRegisterInfo; 37 class raw_ostream; 38 39 /// VNInfo - Value Number Information. 40 /// This class holds information about a machine level values, including 41 /// definition and use points. 42 /// 43 class VNInfo { 44 public: 45 typedef BumpPtrAllocator Allocator; 46 47 /// The ID number of this value. 48 unsigned id; 49 50 /// The index of the defining instruction. 51 SlotIndex def; 52 53 /// VNInfo constructor. 54 VNInfo(unsigned i, SlotIndex d) 55 : id(i), def(d) 56 { } 57 58 /// VNInfo construtor, copies values from orig, except for the value number. 59 VNInfo(unsigned i, const VNInfo &orig) 60 : id(i), def(orig.def) 61 { } 62 63 /// Copy from the parameter into this VNInfo. 64 void copyFrom(VNInfo &src) { 65 def = src.def; 66 } 67 68 /// Returns true if this value is defined by a PHI instruction (or was, 69 /// PHI instrucions may have been eliminated). 70 /// PHI-defs begin at a block boundary, all other defs begin at register or 71 /// EC slots. 72 bool isPHIDef() const { return def.isBlock(); } 73 74 /// Returns true if this value is unused. 75 bool isUnused() const { return !def.isValid(); } 76 77 /// Mark this value as unused. 78 void markUnused() { def = SlotIndex(); } 79 }; 80 81 /// LiveRange structure - This represents a simple register range in the 82 /// program, with an inclusive start point and an exclusive end point. 83 /// These ranges are rendered as [start,end). 84 struct LiveRange { 85 SlotIndex start; // Start point of the interval (inclusive) 86 SlotIndex end; // End point of the interval (exclusive) 87 VNInfo *valno; // identifier for the value contained in this interval. 88 89 LiveRange() : valno(0) {} 90 91 LiveRange(SlotIndex S, SlotIndex E, VNInfo *V) 92 : start(S), end(E), valno(V) { 93 assert(S < E && "Cannot create empty or backwards range"); 94 } 95 96 /// contains - Return true if the index is covered by this range. 97 /// 98 bool contains(SlotIndex I) const { 99 return start <= I && I < end; 100 } 101 102 /// containsRange - Return true if the given range, [S, E), is covered by 103 /// this range. 104 bool containsRange(SlotIndex S, SlotIndex E) const { 105 assert((S < E) && "Backwards interval?"); 106 return (start <= S && S < end) && (start < E && E <= end); 107 } 108 109 bool operator<(const LiveRange &LR) const { 110 return start < LR.start || (start == LR.start && end < LR.end); 111 } 112 bool operator==(const LiveRange &LR) const { 113 return start == LR.start && end == LR.end; 114 } 115 116 void dump() const; 117 void print(raw_ostream &os) const; 118 }; 119 120 template <> struct isPodLike<LiveRange> { static const bool value = true; }; 121 122 raw_ostream& operator<<(raw_ostream& os, const LiveRange &LR); 123 124 125 inline bool operator<(SlotIndex V, const LiveRange &LR) { 126 return V < LR.start; 127 } 128 129 inline bool operator<(const LiveRange &LR, SlotIndex V) { 130 return LR.start < V; 131 } 132 133 /// LiveInterval - This class represents some number of live ranges for a 134 /// register or value. This class also contains a bit of register allocator 135 /// state. 136 class LiveInterval { 137 public: 138 139 typedef SmallVector<LiveRange,4> Ranges; 140 typedef SmallVector<VNInfo*,4> VNInfoList; 141 142 const unsigned reg; // the register or stack slot of this interval. 143 float weight; // weight of this interval 144 Ranges ranges; // the ranges in which this register is live 145 VNInfoList valnos; // value#'s 146 147 struct InstrSlots { 148 enum { 149 LOAD = 0, 150 USE = 1, 151 DEF = 2, 152 STORE = 3, 153 NUM = 4 154 }; 155 156 }; 157 158 LiveInterval(unsigned Reg, float Weight) 159 : reg(Reg), weight(Weight) {} 160 161 typedef Ranges::iterator iterator; 162 iterator begin() { return ranges.begin(); } 163 iterator end() { return ranges.end(); } 164 165 typedef Ranges::const_iterator const_iterator; 166 const_iterator begin() const { return ranges.begin(); } 167 const_iterator end() const { return ranges.end(); } 168 169 typedef VNInfoList::iterator vni_iterator; 170 vni_iterator vni_begin() { return valnos.begin(); } 171 vni_iterator vni_end() { return valnos.end(); } 172 173 typedef VNInfoList::const_iterator const_vni_iterator; 174 const_vni_iterator vni_begin() const { return valnos.begin(); } 175 const_vni_iterator vni_end() const { return valnos.end(); } 176 177 /// advanceTo - Advance the specified iterator to point to the LiveRange 178 /// containing the specified position, or end() if the position is past the 179 /// end of the interval. If no LiveRange contains this position, but the 180 /// position is in a hole, this method returns an iterator pointing to the 181 /// LiveRange immediately after the hole. 182 iterator advanceTo(iterator I, SlotIndex Pos) { 183 assert(I != end()); 184 if (Pos >= endIndex()) 185 return end(); 186 while (I->end <= Pos) ++I; 187 return I; 188 } 189 190 /// find - Return an iterator pointing to the first range that ends after 191 /// Pos, or end(). This is the same as advanceTo(begin(), Pos), but faster 192 /// when searching large intervals. 193 /// 194 /// If Pos is contained in a LiveRange, that range is returned. 195 /// If Pos is in a hole, the following LiveRange is returned. 196 /// If Pos is beyond endIndex, end() is returned. 197 iterator find(SlotIndex Pos); 198 199 const_iterator find(SlotIndex Pos) const { 200 return const_cast<LiveInterval*>(this)->find(Pos); 201 } 202 203 void clear() { 204 valnos.clear(); 205 ranges.clear(); 206 } 207 208 bool hasAtLeastOneValue() const { return !valnos.empty(); } 209 210 bool containsOneValue() const { return valnos.size() == 1; } 211 212 unsigned getNumValNums() const { return (unsigned)valnos.size(); } 213 214 /// getValNumInfo - Returns pointer to the specified val#. 215 /// 216 inline VNInfo *getValNumInfo(unsigned ValNo) { 217 return valnos[ValNo]; 218 } 219 inline const VNInfo *getValNumInfo(unsigned ValNo) const { 220 return valnos[ValNo]; 221 } 222 223 /// containsValue - Returns true if VNI belongs to this interval. 224 bool containsValue(const VNInfo *VNI) const { 225 return VNI && VNI->id < getNumValNums() && VNI == getValNumInfo(VNI->id); 226 } 227 228 /// getNextValue - Create a new value number and return it. MIIdx specifies 229 /// the instruction that defines the value number. 230 VNInfo *getNextValue(SlotIndex def, VNInfo::Allocator &VNInfoAllocator) { 231 VNInfo *VNI = 232 new (VNInfoAllocator) VNInfo((unsigned)valnos.size(), def); 233 valnos.push_back(VNI); 234 return VNI; 235 } 236 237 /// createDeadDef - Make sure the interval has a value defined at Def. 238 /// If one already exists, return it. Otherwise allocate a new value and 239 /// add liveness for a dead def. 240 VNInfo *createDeadDef(SlotIndex Def, VNInfo::Allocator &VNInfoAllocator); 241 242 /// Create a copy of the given value. The new value will be identical except 243 /// for the Value number. 244 VNInfo *createValueCopy(const VNInfo *orig, 245 VNInfo::Allocator &VNInfoAllocator) { 246 VNInfo *VNI = 247 new (VNInfoAllocator) VNInfo((unsigned)valnos.size(), *orig); 248 valnos.push_back(VNI); 249 return VNI; 250 } 251 252 /// RenumberValues - Renumber all values in order of appearance and remove 253 /// unused values. 254 void RenumberValues(LiveIntervals &lis); 255 256 /// MergeValueNumberInto - This method is called when two value nubmers 257 /// are found to be equivalent. This eliminates V1, replacing all 258 /// LiveRanges with the V1 value number with the V2 value number. This can 259 /// cause merging of V1/V2 values numbers and compaction of the value space. 260 VNInfo* MergeValueNumberInto(VNInfo *V1, VNInfo *V2); 261 262 /// MergeValueInAsValue - Merge all of the live ranges of a specific val# 263 /// in RHS into this live interval as the specified value number. 264 /// The LiveRanges in RHS are allowed to overlap with LiveRanges in the 265 /// current interval, it will replace the value numbers of the overlaped 266 /// live ranges with the specified value number. 267 void MergeRangesInAsValue(const LiveInterval &RHS, VNInfo *LHSValNo); 268 269 /// MergeValueInAsValue - Merge all of the live ranges of a specific val# 270 /// in RHS into this live interval as the specified value number. 271 /// The LiveRanges in RHS are allowed to overlap with LiveRanges in the 272 /// current interval, but only if the overlapping LiveRanges have the 273 /// specified value number. 274 void MergeValueInAsValue(const LiveInterval &RHS, 275 const VNInfo *RHSValNo, VNInfo *LHSValNo); 276 277 bool empty() const { return ranges.empty(); } 278 279 /// beginIndex - Return the lowest numbered slot covered by interval. 280 SlotIndex beginIndex() const { 281 assert(!empty() && "Call to beginIndex() on empty interval."); 282 return ranges.front().start; 283 } 284 285 /// endNumber - return the maximum point of the interval of the whole, 286 /// exclusive. 287 SlotIndex endIndex() const { 288 assert(!empty() && "Call to endIndex() on empty interval."); 289 return ranges.back().end; 290 } 291 292 bool expiredAt(SlotIndex index) const { 293 return index >= endIndex(); 294 } 295 296 bool liveAt(SlotIndex index) const { 297 const_iterator r = find(index); 298 return r != end() && r->start <= index; 299 } 300 301 /// killedAt - Return true if a live range ends at index. Note that the kill 302 /// point is not contained in the half-open live range. It is usually the 303 /// getDefIndex() slot following its last use. 304 bool killedAt(SlotIndex index) const { 305 const_iterator r = find(index.getRegSlot(true)); 306 return r != end() && r->end == index; 307 } 308 309 /// getLiveRangeContaining - Return the live range that contains the 310 /// specified index, or null if there is none. 311 const LiveRange *getLiveRangeContaining(SlotIndex Idx) const { 312 const_iterator I = FindLiveRangeContaining(Idx); 313 return I == end() ? 0 : &*I; 314 } 315 316 /// getLiveRangeContaining - Return the live range that contains the 317 /// specified index, or null if there is none. 318 LiveRange *getLiveRangeContaining(SlotIndex Idx) { 319 iterator I = FindLiveRangeContaining(Idx); 320 return I == end() ? 0 : &*I; 321 } 322 323 /// getVNInfoAt - Return the VNInfo that is live at Idx, or NULL. 324 VNInfo *getVNInfoAt(SlotIndex Idx) const { 325 const_iterator I = FindLiveRangeContaining(Idx); 326 return I == end() ? 0 : I->valno; 327 } 328 329 /// getVNInfoBefore - Return the VNInfo that is live up to but not 330 /// necessarilly including Idx, or NULL. Use this to find the reaching def 331 /// used by an instruction at this SlotIndex position. 332 VNInfo *getVNInfoBefore(SlotIndex Idx) const { 333 const_iterator I = FindLiveRangeContaining(Idx.getPrevSlot()); 334 return I == end() ? 0 : I->valno; 335 } 336 337 /// FindLiveRangeContaining - Return an iterator to the live range that 338 /// contains the specified index, or end() if there is none. 339 iterator FindLiveRangeContaining(SlotIndex Idx) { 340 iterator I = find(Idx); 341 return I != end() && I->start <= Idx ? I : end(); 342 } 343 344 const_iterator FindLiveRangeContaining(SlotIndex Idx) const { 345 const_iterator I = find(Idx); 346 return I != end() && I->start <= Idx ? I : end(); 347 } 348 349 /// overlaps - Return true if the intersection of the two live intervals is 350 /// not empty. 351 bool overlaps(const LiveInterval& other) const { 352 if (other.empty()) 353 return false; 354 return overlapsFrom(other, other.begin()); 355 } 356 357 /// overlaps - Return true if the two intervals have overlapping segments 358 /// that are not coalescable according to CP. 359 /// 360 /// Overlapping segments where one interval is defined by a coalescable 361 /// copy are allowed. 362 bool overlaps(const LiveInterval &Other, const CoalescerPair &CP, 363 const SlotIndexes&) const; 364 365 /// overlaps - Return true if the live interval overlaps a range specified 366 /// by [Start, End). 367 bool overlaps(SlotIndex Start, SlotIndex End) const; 368 369 /// overlapsFrom - Return true if the intersection of the two live intervals 370 /// is not empty. The specified iterator is a hint that we can begin 371 /// scanning the Other interval starting at I. 372 bool overlapsFrom(const LiveInterval& other, const_iterator I) const; 373 374 /// addRange - Add the specified LiveRange to this interval, merging 375 /// intervals as appropriate. This returns an iterator to the inserted live 376 /// range (which may have grown since it was inserted. 377 iterator addRange(LiveRange LR) { 378 return addRangeFrom(LR, ranges.begin()); 379 } 380 381 /// extendInBlock - If this interval is live before Kill in the basic block 382 /// that starts at StartIdx, extend it to be live up to Kill, and return 383 /// the value. If there is no live range before Kill, return NULL. 384 VNInfo *extendInBlock(SlotIndex StartIdx, SlotIndex Kill); 385 386 /// join - Join two live intervals (this, and other) together. This applies 387 /// mappings to the value numbers in the LHS/RHS intervals as specified. If 388 /// the intervals are not joinable, this aborts. 389 void join(LiveInterval &Other, 390 const int *ValNoAssignments, 391 const int *RHSValNoAssignments, 392 SmallVector<VNInfo*, 16> &NewVNInfo, 393 MachineRegisterInfo *MRI); 394 395 /// isInOneLiveRange - Return true if the range specified is entirely in the 396 /// a single LiveRange of the live interval. 397 bool isInOneLiveRange(SlotIndex Start, SlotIndex End) const { 398 const_iterator r = find(Start); 399 return r != end() && r->containsRange(Start, End); 400 } 401 402 /// removeRange - Remove the specified range from this interval. Note that 403 /// the range must be a single LiveRange in its entirety. 404 void removeRange(SlotIndex Start, SlotIndex End, 405 bool RemoveDeadValNo = false); 406 407 void removeRange(LiveRange LR, bool RemoveDeadValNo = false) { 408 removeRange(LR.start, LR.end, RemoveDeadValNo); 409 } 410 411 /// removeValNo - Remove all the ranges defined by the specified value#. 412 /// Also remove the value# from value# list. 413 void removeValNo(VNInfo *ValNo); 414 415 /// getSize - Returns the sum of sizes of all the LiveRange's. 416 /// 417 unsigned getSize() const; 418 419 /// Returns true if the live interval is zero length, i.e. no live ranges 420 /// span instructions. It doesn't pay to spill such an interval. 421 bool isZeroLength(SlotIndexes *Indexes) const { 422 for (const_iterator i = begin(), e = end(); i != e; ++i) 423 if (Indexes->getNextNonNullIndex(i->start).getBaseIndex() < 424 i->end.getBaseIndex()) 425 return false; 426 return true; 427 } 428 429 /// isSpillable - Can this interval be spilled? 430 bool isSpillable() const { 431 return weight != HUGE_VALF; 432 } 433 434 /// markNotSpillable - Mark interval as not spillable 435 void markNotSpillable() { 436 weight = HUGE_VALF; 437 } 438 439 bool operator<(const LiveInterval& other) const { 440 const SlotIndex &thisIndex = beginIndex(); 441 const SlotIndex &otherIndex = other.beginIndex(); 442 return (thisIndex < otherIndex || 443 (thisIndex == otherIndex && reg < other.reg)); 444 } 445 446 void print(raw_ostream &OS) const; 447 void dump() const; 448 449 /// \brief Walk the interval and assert if any invariants fail to hold. 450 /// 451 /// Note that this is a no-op when asserts are disabled. 452 #ifdef NDEBUG 453 void verify() const {} 454 #else 455 void verify() const; 456 #endif 457 458 private: 459 460 Ranges::iterator addRangeFrom(LiveRange LR, Ranges::iterator From); 461 void extendIntervalEndTo(Ranges::iterator I, SlotIndex NewEnd); 462 Ranges::iterator extendIntervalStartTo(Ranges::iterator I, SlotIndex NewStr); 463 void markValNoForDeletion(VNInfo *V); 464 465 LiveInterval& operator=(const LiveInterval& rhs) LLVM_DELETED_FUNCTION; 466 467 }; 468 469 inline raw_ostream &operator<<(raw_ostream &OS, const LiveInterval &LI) { 470 LI.print(OS); 471 return OS; 472 } 473 474 /// Helper class for performant LiveInterval bulk updates. 475 /// 476 /// Calling LiveInterval::addRange() repeatedly can be expensive on large 477 /// live ranges because segments after the insertion point may need to be 478 /// shifted. The LiveRangeUpdater class can defer the shifting when adding 479 /// many segments in order. 480 /// 481 /// The LiveInterval will be in an invalid state until flush() is called. 482 class LiveRangeUpdater { 483 LiveInterval *LI; 484 SlotIndex LastStart; 485 LiveInterval::iterator WriteI; 486 LiveInterval::iterator ReadI; 487 SmallVector<LiveRange, 16> Spills; 488 void mergeSpills(); 489 490 public: 491 /// Create a LiveRangeUpdater for adding segments to LI. 492 /// LI will temporarily be in an invalid state until flush() is called. 493 LiveRangeUpdater(LiveInterval *li = 0) : LI(li) {} 494 495 ~LiveRangeUpdater() { flush(); } 496 497 /// Add a segment to LI and coalesce when possible, just like LI.addRange(). 498 /// Segments should be added in increasing start order for best performance. 499 void add(LiveRange); 500 501 void add(SlotIndex Start, SlotIndex End, VNInfo *VNI) { 502 add(LiveRange(Start, End, VNI)); 503 } 504 505 /// Return true if the LI is currently in an invalid state, and flush() 506 /// needs to be called. 507 bool isDirty() const { return LastStart.isValid(); } 508 509 /// Flush the updater state to LI so it is valid and contains all added 510 /// segments. 511 void flush(); 512 513 /// Select a different destination live range. 514 void setDest(LiveInterval *li) { 515 if (LI != li && isDirty()) 516 flush(); 517 LI = li; 518 } 519 520 /// Get the current destination live range. 521 LiveInterval *getDest() const { return LI; } 522 523 void dump() const; 524 void print(raw_ostream&) const; 525 }; 526 527 inline raw_ostream &operator<<(raw_ostream &OS, const LiveRangeUpdater &X) { 528 X.print(OS); 529 return OS; 530 } 531 532 /// LiveRangeQuery - Query information about a live range around a given 533 /// instruction. This class hides the implementation details of live ranges, 534 /// and it should be used as the primary interface for examining live ranges 535 /// around instructions. 536 /// 537 class LiveRangeQuery { 538 VNInfo *EarlyVal; 539 VNInfo *LateVal; 540 SlotIndex EndPoint; 541 bool Kill; 542 543 public: 544 /// Create a LiveRangeQuery for the given live range and instruction index. 545 /// The sub-instruction slot of Idx doesn't matter, only the instruction it 546 /// refers to is considered. 547 LiveRangeQuery(const LiveInterval &LI, SlotIndex Idx) 548 : EarlyVal(0), LateVal(0), Kill(false) { 549 // Find the segment that enters the instruction. 550 LiveInterval::const_iterator I = LI.find(Idx.getBaseIndex()); 551 LiveInterval::const_iterator E = LI.end(); 552 if (I == E) 553 return; 554 // Is this an instruction live-in segment? 555 // If Idx is the start index of a basic block, include live-in segments 556 // that start at Idx.getBaseIndex(). 557 if (I->start <= Idx.getBaseIndex()) { 558 EarlyVal = I->valno; 559 EndPoint = I->end; 560 // Move to the potentially live-out segment. 561 if (SlotIndex::isSameInstr(Idx, I->end)) { 562 Kill = true; 563 if (++I == E) 564 return; 565 } 566 // Special case: A PHIDef value can have its def in the middle of a 567 // segment if the value happens to be live out of the layout 568 // predecessor. 569 // Such a value is not live-in. 570 if (EarlyVal->def == Idx.getBaseIndex()) 571 EarlyVal = 0; 572 } 573 // I now points to the segment that may be live-through, or defined by 574 // this instr. Ignore segments starting after the current instr. 575 if (SlotIndex::isEarlierInstr(Idx, I->start)) 576 return; 577 LateVal = I->valno; 578 EndPoint = I->end; 579 } 580 581 /// Return the value that is live-in to the instruction. This is the value 582 /// that will be read by the instruction's use operands. Return NULL if no 583 /// value is live-in. 584 VNInfo *valueIn() const { 585 return EarlyVal; 586 } 587 588 /// Return true if the live-in value is killed by this instruction. This 589 /// means that either the live range ends at the instruction, or it changes 590 /// value. 591 bool isKill() const { 592 return Kill; 593 } 594 595 /// Return true if this instruction has a dead def. 596 bool isDeadDef() const { 597 return EndPoint.isDead(); 598 } 599 600 /// Return the value leaving the instruction, if any. This can be a 601 /// live-through value, or a live def. A dead def returns NULL. 602 VNInfo *valueOut() const { 603 return isDeadDef() ? 0 : LateVal; 604 } 605 606 /// Return the value defined by this instruction, if any. This includes 607 /// dead defs, it is the value created by the instruction's def operands. 608 VNInfo *valueDefined() const { 609 return EarlyVal == LateVal ? 0 : LateVal; 610 } 611 612 /// Return the end point of the last live range segment to interact with 613 /// the instruction, if any. 614 /// 615 /// The end point is an invalid SlotIndex only if the live range doesn't 616 /// intersect the instruction at all. 617 /// 618 /// The end point may be at or past the end of the instruction's basic 619 /// block. That means the value was live out of the block. 620 SlotIndex endPoint() const { 621 return EndPoint; 622 } 623 }; 624 625 /// ConnectedVNInfoEqClasses - Helper class that can divide VNInfos in a 626 /// LiveInterval into equivalence clases of connected components. A 627 /// LiveInterval that has multiple connected components can be broken into 628 /// multiple LiveIntervals. 629 /// 630 /// Given a LiveInterval that may have multiple connected components, run: 631 /// 632 /// unsigned numComps = ConEQ.Classify(LI); 633 /// if (numComps > 1) { 634 /// // allocate numComps-1 new LiveIntervals into LIS[1..] 635 /// ConEQ.Distribute(LIS); 636 /// } 637 638 class ConnectedVNInfoEqClasses { 639 LiveIntervals &LIS; 640 IntEqClasses EqClass; 641 642 // Note that values a and b are connected. 643 void Connect(unsigned a, unsigned b); 644 645 unsigned Renumber(); 646 647 public: 648 explicit ConnectedVNInfoEqClasses(LiveIntervals &lis) : LIS(lis) {} 649 650 /// Classify - Classify the values in LI into connected components. 651 /// Return the number of connected components. 652 unsigned Classify(const LiveInterval *LI); 653 654 /// getEqClass - Classify creates equivalence classes numbered 0..N. Return 655 /// the equivalence class assigned the VNI. 656 unsigned getEqClass(const VNInfo *VNI) const { return EqClass[VNI->id]; } 657 658 /// Distribute - Distribute values in LIV[0] into a separate LiveInterval 659 /// for each connected component. LIV must have a LiveInterval for each 660 /// connected component. The LiveIntervals in Liv[1..] must be empty. 661 /// Instructions using LIV[0] are rewritten. 662 void Distribute(LiveInterval *LIV[], MachineRegisterInfo &MRI); 663 664 }; 665 666 } 667 #endif 668