1 // Copyright 2012 the V8 project authors. All rights reserved.
2 // Redistribution and use in source and binary forms, with or without
3 // modification, are permitted provided that the following conditions are
6 // * Redistributions of source code must retain the above copyright
7 // notice, this list of conditions and the following disclaimer.
8 // * Redistributions in binary form must reproduce the above
9 // copyright notice, this list of conditions and the following
10 // disclaimer in the documentation and/or other materials provided
11 // with the distribution.
12 // * Neither the name of Google Inc. nor the names of its
13 // contributors may be used to endorse or promote products derived
14 // from this software without specific prior written permission.
16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 #include "lithium-allocator-inl.h"
32 #include "string-stream.h"
34 #if V8_TARGET_ARCH_IA32
35 #include "ia32/lithium-ia32.h"
36 #elif V8_TARGET_ARCH_X64
37 #include "x64/lithium-x64.h"
38 #elif V8_TARGET_ARCH_ARM
39 #include "arm/lithium-arm.h"
40 #elif V8_TARGET_ARCH_MIPS
41 #include "mips/lithium-mips.h"
43 #error "Unknown architecture."
49 static inline LifetimePosition Min(LifetimePosition a, LifetimePosition b) {
50 return a.Value() < b.Value() ? a : b;
54 static inline LifetimePosition Max(LifetimePosition a, LifetimePosition b) {
55 return a.Value() > b.Value() ? a : b;
59 UsePosition::UsePosition(LifetimePosition pos,
67 register_beneficial_(true) {
68 if (operand_ != NULL && operand_->IsUnallocated()) {
69 LUnallocated* unalloc = LUnallocated::cast(operand_);
70 requires_reg_ = unalloc->HasRegisterPolicy();
71 register_beneficial_ = !unalloc->HasAnyPolicy();
73 ASSERT(pos_.IsValid());
77 bool UsePosition::HasHint() const {
78 return hint_ != NULL && !hint_->IsUnallocated();
82 bool UsePosition::RequiresRegister() const {
87 bool UsePosition::RegisterIsBeneficial() const {
88 return register_beneficial_;
92 void UseInterval::SplitAt(LifetimePosition pos, Zone* zone) {
93 ASSERT(Contains(pos) && pos.Value() != start().Value());
94 UseInterval* after = new(zone) UseInterval(pos, end_);
104 void LiveRange::Verify() const {
105 UsePosition* cur = first_pos_;
106 while (cur != NULL) {
107 ASSERT(Start().Value() <= cur->pos().Value() &&
108 cur->pos().Value() <= End().Value());
114 bool LiveRange::HasOverlap(UseInterval* target) const {
115 UseInterval* current_interval = first_interval_;
116 while (current_interval != NULL) {
117 // Intervals overlap if the start of one is contained in the other.
118 if (current_interval->Contains(target->start()) ||
119 target->Contains(current_interval->start())) {
122 current_interval = current_interval->next();
131 LiveRange::LiveRange(int id, Zone* zone)
134 kind_(UNALLOCATED_REGISTERS),
135 assigned_register_(kInvalidAssignment),
136 last_interval_(NULL),
137 first_interval_(NULL),
141 current_interval_(NULL),
142 last_processed_use_(NULL),
143 current_hint_operand_(NULL),
144 spill_operand_(new(zone) LOperand()),
145 spill_start_index_(kMaxInt) { }
148 void LiveRange::set_assigned_register(int reg, Zone* zone) {
149 ASSERT(!HasRegisterAssigned() && !IsSpilled());
150 assigned_register_ = reg;
151 ConvertOperands(zone);
155 void LiveRange::MakeSpilled(Zone* zone) {
156 ASSERT(!IsSpilled());
157 ASSERT(TopLevel()->HasAllocatedSpillOperand());
159 assigned_register_ = kInvalidAssignment;
160 ConvertOperands(zone);
164 bool LiveRange::HasAllocatedSpillOperand() const {
165 ASSERT(spill_operand_ != NULL);
166 return !spill_operand_->IsIgnored();
170 void LiveRange::SetSpillOperand(LOperand* operand) {
171 ASSERT(!operand->IsUnallocated());
172 ASSERT(spill_operand_ != NULL);
173 ASSERT(spill_operand_->IsIgnored());
174 spill_operand_->ConvertTo(operand->kind(), operand->index());
178 UsePosition* LiveRange::NextUsePosition(LifetimePosition start) {
179 UsePosition* use_pos = last_processed_use_;
180 if (use_pos == NULL) use_pos = first_pos();
181 while (use_pos != NULL && use_pos->pos().Value() < start.Value()) {
182 use_pos = use_pos->next();
184 last_processed_use_ = use_pos;
189 UsePosition* LiveRange::NextUsePositionRegisterIsBeneficial(
190 LifetimePosition start) {
191 UsePosition* pos = NextUsePosition(start);
192 while (pos != NULL && !pos->RegisterIsBeneficial()) {
199 UsePosition* LiveRange::PreviousUsePositionRegisterIsBeneficial(
200 LifetimePosition start) {
201 UsePosition* pos = first_pos();
202 UsePosition* prev = NULL;
203 while (pos != NULL && pos->pos().Value() < start.Value()) {
204 if (pos->RegisterIsBeneficial()) prev = pos;
211 UsePosition* LiveRange::NextRegisterPosition(LifetimePosition start) {
212 UsePosition* pos = NextUsePosition(start);
213 while (pos != NULL && !pos->RequiresRegister()) {
220 bool LiveRange::CanBeSpilled(LifetimePosition pos) {
221 // We cannot spill a live range that has a use requiring a register
222 // at the current or the immediate next position.
223 UsePosition* use_pos = NextRegisterPosition(pos);
224 if (use_pos == NULL) return true;
226 use_pos->pos().Value() > pos.NextInstruction().InstructionEnd().Value();
230 LOperand* LiveRange::CreateAssignedOperand(Zone* zone) {
232 if (HasRegisterAssigned()) {
233 ASSERT(!IsSpilled());
235 case GENERAL_REGISTERS:
236 op = LRegister::Create(assigned_register(), zone);
238 case DOUBLE_REGISTERS:
239 op = LDoubleRegister::Create(assigned_register(), zone);
244 } else if (IsSpilled()) {
245 ASSERT(!HasRegisterAssigned());
246 op = TopLevel()->GetSpillOperand();
247 ASSERT(!op->IsUnallocated());
249 LUnallocated* unalloc = new(zone) LUnallocated(LUnallocated::NONE);
250 unalloc->set_virtual_register(id_);
257 UseInterval* LiveRange::FirstSearchIntervalForPosition(
258 LifetimePosition position) const {
259 if (current_interval_ == NULL) return first_interval_;
260 if (current_interval_->start().Value() > position.Value()) {
261 current_interval_ = NULL;
262 return first_interval_;
264 return current_interval_;
268 void LiveRange::AdvanceLastProcessedMarker(
269 UseInterval* to_start_of, LifetimePosition but_not_past) const {
270 if (to_start_of == NULL) return;
271 if (to_start_of->start().Value() > but_not_past.Value()) return;
272 LifetimePosition start =
273 current_interval_ == NULL ? LifetimePosition::Invalid()
274 : current_interval_->start();
275 if (to_start_of->start().Value() > start.Value()) {
276 current_interval_ = to_start_of;
281 void LiveRange::SplitAt(LifetimePosition position,
284 ASSERT(Start().Value() < position.Value());
285 ASSERT(result->IsEmpty());
286 // Find the last interval that ends before the position. If the
287 // position is contained in one of the intervals in the chain, we
288 // split that interval and use the first part.
289 UseInterval* current = FirstSearchIntervalForPosition(position);
291 // If the split position coincides with the beginning of a use interval
292 // we need to split use positons in a special way.
293 bool split_at_start = false;
295 if (current->start().Value() == position.Value()) {
296 // When splitting at start we need to locate the previous use interval.
297 current = first_interval_;
300 while (current != NULL) {
301 if (current->Contains(position)) {
302 current->SplitAt(position, zone);
305 UseInterval* next = current->next();
306 if (next->start().Value() >= position.Value()) {
307 split_at_start = (next->start().Value() == position.Value());
313 // Partition original use intervals to the two live ranges.
314 UseInterval* before = current;
315 UseInterval* after = before->next();
316 result->last_interval_ = (last_interval_ == before)
317 ? after // Only interval in the range after split.
318 : last_interval_; // Last interval of the original range.
319 result->first_interval_ = after;
320 last_interval_ = before;
322 // Find the last use position before the split and the first use
323 // position after it.
324 UsePosition* use_after = first_pos_;
325 UsePosition* use_before = NULL;
326 if (split_at_start) {
327 // The split position coincides with the beginning of a use interval (the
328 // end of a lifetime hole). Use at this position should be attributed to
329 // the split child because split child owns use interval covering it.
330 while (use_after != NULL && use_after->pos().Value() < position.Value()) {
331 use_before = use_after;
332 use_after = use_after->next();
335 while (use_after != NULL && use_after->pos().Value() <= position.Value()) {
336 use_before = use_after;
337 use_after = use_after->next();
341 // Partition original use positions to the two live ranges.
342 if (use_before != NULL) {
343 use_before->next_ = NULL;
347 result->first_pos_ = use_after;
349 // Discard cached iteration state. It might be pointing
350 // to the use that no longer belongs to this live range.
351 last_processed_use_ = NULL;
352 current_interval_ = NULL;
354 // Link the new live range in the chain before any of the other
355 // ranges linked from the range before the split.
356 result->parent_ = (parent_ == NULL) ? this : parent_;
357 result->kind_ = result->parent_->kind_;
358 result->next_ = next_;
368 // This implements an ordering on live ranges so that they are ordered by their
369 // start positions. This is needed for the correctness of the register
370 // allocation algorithm. If two live ranges start at the same offset then there
371 // is a tie breaker based on where the value is first used. This part of the
372 // ordering is merely a heuristic.
373 bool LiveRange::ShouldBeAllocatedBefore(const LiveRange* other) const {
374 LifetimePosition start = Start();
375 LifetimePosition other_start = other->Start();
376 if (start.Value() == other_start.Value()) {
377 UsePosition* pos = first_pos();
378 if (pos == NULL) return false;
379 UsePosition* other_pos = other->first_pos();
380 if (other_pos == NULL) return true;
381 return pos->pos().Value() < other_pos->pos().Value();
383 return start.Value() < other_start.Value();
387 void LiveRange::ShortenTo(LifetimePosition start) {
388 LAllocator::TraceAlloc("Shorten live range %d to [%d\n", id_, start.Value());
389 ASSERT(first_interval_ != NULL);
390 ASSERT(first_interval_->start().Value() <= start.Value());
391 ASSERT(start.Value() < first_interval_->end().Value());
392 first_interval_->set_start(start);
396 void LiveRange::EnsureInterval(LifetimePosition start,
397 LifetimePosition end,
399 LAllocator::TraceAlloc("Ensure live range %d in interval [%d %d[\n",
403 LifetimePosition new_end = end;
404 while (first_interval_ != NULL &&
405 first_interval_->start().Value() <= end.Value()) {
406 if (first_interval_->end().Value() > end.Value()) {
407 new_end = first_interval_->end();
409 first_interval_ = first_interval_->next();
412 UseInterval* new_interval = new(zone) UseInterval(start, new_end);
413 new_interval->next_ = first_interval_;
414 first_interval_ = new_interval;
415 if (new_interval->next() == NULL) {
416 last_interval_ = new_interval;
421 void LiveRange::AddUseInterval(LifetimePosition start,
422 LifetimePosition end,
424 LAllocator::TraceAlloc("Add to live range %d interval [%d %d[\n",
428 if (first_interval_ == NULL) {
429 UseInterval* interval = new(zone) UseInterval(start, end);
430 first_interval_ = interval;
431 last_interval_ = interval;
433 if (end.Value() == first_interval_->start().Value()) {
434 first_interval_->set_start(start);
435 } else if (end.Value() < first_interval_->start().Value()) {
436 UseInterval* interval = new(zone) UseInterval(start, end);
437 interval->set_next(first_interval_);
438 first_interval_ = interval;
440 // Order of instruction's processing (see ProcessInstructions) guarantees
441 // that each new use interval either precedes or intersects with
442 // last added interval.
443 ASSERT(start.Value() < first_interval_->end().Value());
444 first_interval_->start_ = Min(start, first_interval_->start_);
445 first_interval_->end_ = Max(end, first_interval_->end_);
451 void LiveRange::AddUsePosition(LifetimePosition pos,
455 LAllocator::TraceAlloc("Add to live range %d use position %d\n",
458 UsePosition* use_pos = new(zone) UsePosition(pos, operand, hint);
459 UsePosition* prev_hint = NULL;
460 UsePosition* prev = NULL;
461 UsePosition* current = first_pos_;
462 while (current != NULL && current->pos().Value() < pos.Value()) {
463 prev_hint = current->HasHint() ? current : prev_hint;
465 current = current->next();
469 use_pos->set_next(first_pos_);
470 first_pos_ = use_pos;
472 use_pos->next_ = prev->next_;
473 prev->next_ = use_pos;
476 if (prev_hint == NULL && use_pos->HasHint()) {
477 current_hint_operand_ = hint;
482 void LiveRange::ConvertOperands(Zone* zone) {
483 LOperand* op = CreateAssignedOperand(zone);
484 UsePosition* use_pos = first_pos();
485 while (use_pos != NULL) {
486 ASSERT(Start().Value() <= use_pos->pos().Value() &&
487 use_pos->pos().Value() <= End().Value());
489 if (use_pos->HasOperand()) {
490 ASSERT(op->IsRegister() || op->IsDoubleRegister() ||
491 !use_pos->RequiresRegister());
492 use_pos->operand()->ConvertTo(op->kind(), op->index());
494 use_pos = use_pos->next();
499 bool LiveRange::CanCover(LifetimePosition position) const {
500 if (IsEmpty()) return false;
501 return Start().Value() <= position.Value() &&
502 position.Value() < End().Value();
506 bool LiveRange::Covers(LifetimePosition position) {
507 if (!CanCover(position)) return false;
508 UseInterval* start_search = FirstSearchIntervalForPosition(position);
509 for (UseInterval* interval = start_search;
511 interval = interval->next()) {
512 ASSERT(interval->next() == NULL ||
513 interval->next()->start().Value() >= interval->start().Value());
514 AdvanceLastProcessedMarker(interval, position);
515 if (interval->Contains(position)) return true;
516 if (interval->start().Value() > position.Value()) return false;
522 LifetimePosition LiveRange::FirstIntersection(LiveRange* other) {
523 UseInterval* b = other->first_interval();
524 if (b == NULL) return LifetimePosition::Invalid();
525 LifetimePosition advance_last_processed_up_to = b->start();
526 UseInterval* a = FirstSearchIntervalForPosition(b->start());
527 while (a != NULL && b != NULL) {
528 if (a->start().Value() > other->End().Value()) break;
529 if (b->start().Value() > End().Value()) break;
530 LifetimePosition cur_intersection = a->Intersect(b);
531 if (cur_intersection.IsValid()) {
532 return cur_intersection;
534 if (a->start().Value() < b->start().Value()) {
536 if (a == NULL || a->start().Value() > other->End().Value()) break;
537 AdvanceLastProcessedMarker(a, advance_last_processed_up_to);
542 return LifetimePosition::Invalid();
546 LAllocator::LAllocator(int num_values, HGraph* graph)
547 : zone_(graph->isolate()),
549 live_in_sets_(graph->blocks()->length(), zone()),
550 live_ranges_(num_values * 2, zone()),
551 fixed_live_ranges_(NULL),
552 fixed_double_live_ranges_(NULL),
553 unhandled_live_ranges_(num_values * 2, zone()),
554 active_live_ranges_(8, zone()),
555 inactive_live_ranges_(8, zone()),
556 reusable_slots_(8, zone()),
557 next_virtual_register_(num_values),
558 first_artificial_register_(num_values),
559 mode_(UNALLOCATED_REGISTERS),
562 has_osr_entry_(false),
563 allocation_ok_(true) { }
566 void LAllocator::InitializeLivenessAnalysis() {
567 // Initialize the live_in sets for each block to NULL.
568 int block_count = graph_->blocks()->length();
569 live_in_sets_.Initialize(block_count, zone());
570 live_in_sets_.AddBlock(NULL, block_count, zone());
574 BitVector* LAllocator::ComputeLiveOut(HBasicBlock* block) {
575 // Compute live out for the given block, except not including backward
577 BitVector* live_out = new(zone()) BitVector(next_virtual_register_, zone());
579 // Process all successor blocks.
580 for (HSuccessorIterator it(block->end()); !it.Done(); it.Advance()) {
581 // Add values live on entry to the successor. Note the successor's
582 // live_in will not be computed yet for backwards edges.
583 HBasicBlock* successor = it.Current();
584 BitVector* live_in = live_in_sets_[successor->block_id()];
585 if (live_in != NULL) live_out->Union(*live_in);
587 // All phi input operands corresponding to this successor edge are live
588 // out from this block.
589 int index = successor->PredecessorIndexOf(block);
590 const ZoneList<HPhi*>* phis = successor->phis();
591 for (int i = 0; i < phis->length(); ++i) {
592 HPhi* phi = phis->at(i);
593 if (!phi->OperandAt(index)->IsConstant()) {
594 live_out->Add(phi->OperandAt(index)->id());
603 void LAllocator::AddInitialIntervals(HBasicBlock* block,
604 BitVector* live_out) {
605 // Add an interval that includes the entire block to the live range for
606 // each live_out value.
607 LifetimePosition start = LifetimePosition::FromInstructionIndex(
608 block->first_instruction_index());
609 LifetimePosition end = LifetimePosition::FromInstructionIndex(
610 block->last_instruction_index()).NextInstruction();
611 BitVector::Iterator iterator(live_out);
612 while (!iterator.Done()) {
613 int operand_index = iterator.Current();
614 LiveRange* range = LiveRangeFor(operand_index);
615 range->AddUseInterval(start, end, zone());
621 int LAllocator::FixedDoubleLiveRangeID(int index) {
622 return -index - 1 - Register::kMaxNumAllocatableRegisters;
626 LOperand* LAllocator::AllocateFixed(LUnallocated* operand,
629 TraceAlloc("Allocating fixed reg for op %d\n", operand->virtual_register());
630 ASSERT(operand->HasFixedPolicy());
631 if (operand->HasFixedSlotPolicy()) {
632 operand->ConvertTo(LOperand::STACK_SLOT, operand->fixed_slot_index());
633 } else if (operand->HasFixedRegisterPolicy()) {
634 int reg_index = operand->fixed_register_index();
635 operand->ConvertTo(LOperand::REGISTER, reg_index);
636 } else if (operand->HasFixedDoubleRegisterPolicy()) {
637 int reg_index = operand->fixed_register_index();
638 operand->ConvertTo(LOperand::DOUBLE_REGISTER, reg_index);
643 TraceAlloc("Fixed reg is tagged at %d\n", pos);
644 LInstruction* instr = InstructionAt(pos);
645 if (instr->HasPointerMap()) {
646 instr->pointer_map()->RecordPointer(operand, chunk()->zone());
653 LiveRange* LAllocator::FixedLiveRangeFor(int index) {
654 ASSERT(index < Register::kMaxNumAllocatableRegisters);
655 LiveRange* result = fixed_live_ranges_[index];
656 if (result == NULL) {
657 result = new(zone()) LiveRange(FixedLiveRangeID(index), chunk()->zone());
658 ASSERT(result->IsFixed());
659 result->kind_ = GENERAL_REGISTERS;
660 SetLiveRangeAssignedRegister(result, index);
661 fixed_live_ranges_[index] = result;
667 LiveRange* LAllocator::FixedDoubleLiveRangeFor(int index) {
668 ASSERT(index < DoubleRegister::NumAllocatableRegisters());
669 LiveRange* result = fixed_double_live_ranges_[index];
670 if (result == NULL) {
671 result = new(zone()) LiveRange(FixedDoubleLiveRangeID(index),
673 ASSERT(result->IsFixed());
674 result->kind_ = DOUBLE_REGISTERS;
675 SetLiveRangeAssignedRegister(result, index);
676 fixed_double_live_ranges_[index] = result;
682 LiveRange* LAllocator::LiveRangeFor(int index) {
683 if (index >= live_ranges_.length()) {
684 live_ranges_.AddBlock(NULL, index - live_ranges_.length() + 1, zone());
686 LiveRange* result = live_ranges_[index];
687 if (result == NULL) {
688 result = new(zone()) LiveRange(index, chunk()->zone());
689 live_ranges_[index] = result;
695 LGap* LAllocator::GetLastGap(HBasicBlock* block) {
696 int last_instruction = block->last_instruction_index();
697 int index = chunk_->NearestGapPos(last_instruction);
702 HPhi* LAllocator::LookupPhi(LOperand* operand) const {
703 if (!operand->IsUnallocated()) return NULL;
704 int index = LUnallocated::cast(operand)->virtual_register();
705 HValue* instr = graph_->LookupValue(index);
706 if (instr != NULL && instr->IsPhi()) {
707 return HPhi::cast(instr);
713 LiveRange* LAllocator::LiveRangeFor(LOperand* operand) {
714 if (operand->IsUnallocated()) {
715 return LiveRangeFor(LUnallocated::cast(operand)->virtual_register());
716 } else if (operand->IsRegister()) {
717 return FixedLiveRangeFor(operand->index());
718 } else if (operand->IsDoubleRegister()) {
719 return FixedDoubleLiveRangeFor(operand->index());
726 void LAllocator::Define(LifetimePosition position,
729 LiveRange* range = LiveRangeFor(operand);
730 if (range == NULL) return;
732 if (range->IsEmpty() || range->Start().Value() > position.Value()) {
733 // Can happen if there is a definition without use.
734 range->AddUseInterval(position, position.NextInstruction(), zone());
735 range->AddUsePosition(position.NextInstruction(), NULL, NULL, zone());
737 range->ShortenTo(position);
740 if (operand->IsUnallocated()) {
741 LUnallocated* unalloc_operand = LUnallocated::cast(operand);
742 range->AddUsePosition(position, unalloc_operand, hint, zone());
747 void LAllocator::Use(LifetimePosition block_start,
748 LifetimePosition position,
751 LiveRange* range = LiveRangeFor(operand);
752 if (range == NULL) return;
753 if (operand->IsUnallocated()) {
754 LUnallocated* unalloc_operand = LUnallocated::cast(operand);
755 range->AddUsePosition(position, unalloc_operand, hint, zone());
757 range->AddUseInterval(block_start, position, zone());
761 void LAllocator::AddConstraintsGapMove(int index,
764 LGap* gap = GapAt(index);
765 LParallelMove* move = gap->GetOrCreateParallelMove(LGap::START,
767 if (from->IsUnallocated()) {
768 const ZoneList<LMoveOperands>* move_operands = move->move_operands();
769 for (int i = 0; i < move_operands->length(); ++i) {
770 LMoveOperands cur = move_operands->at(i);
771 LOperand* cur_to = cur.destination();
772 if (cur_to->IsUnallocated()) {
773 if (LUnallocated::cast(cur_to)->virtual_register() ==
774 LUnallocated::cast(from)->virtual_register()) {
775 move->AddMove(cur.source(), to, chunk()->zone());
781 move->AddMove(from, to, chunk()->zone());
785 void LAllocator::MeetRegisterConstraints(HBasicBlock* block) {
786 int start = block->first_instruction_index();
787 int end = block->last_instruction_index();
788 if (start == -1) return;
789 for (int i = start; i <= end; ++i) {
791 LInstruction* instr = NULL;
792 LInstruction* prev_instr = NULL;
793 if (i < end) instr = InstructionAt(i + 1);
794 if (i > start) prev_instr = InstructionAt(i - 1);
795 MeetConstraintsBetween(prev_instr, instr, i);
796 if (!AllocationOk()) return;
802 void LAllocator::MeetConstraintsBetween(LInstruction* first,
803 LInstruction* second,
805 // Handle fixed temporaries.
807 for (TempIterator it(first); !it.Done(); it.Advance()) {
808 LUnallocated* temp = LUnallocated::cast(it.Current());
809 if (temp->HasFixedPolicy()) {
810 AllocateFixed(temp, gap_index - 1, false);
815 // Handle fixed output operand.
816 if (first != NULL && first->Output() != NULL) {
817 LUnallocated* first_output = LUnallocated::cast(first->Output());
818 LiveRange* range = LiveRangeFor(first_output->virtual_register());
819 bool assigned = false;
820 if (first_output->HasFixedPolicy()) {
821 LUnallocated* output_copy = first_output->CopyUnconstrained(
823 bool is_tagged = HasTaggedValue(first_output->virtual_register());
824 AllocateFixed(first_output, gap_index, is_tagged);
826 // This value is produced on the stack, we never need to spill it.
827 if (first_output->IsStackSlot()) {
828 range->SetSpillOperand(first_output);
829 range->SetSpillStartIndex(gap_index - 1);
832 chunk_->AddGapMove(gap_index, first_output, output_copy);
836 range->SetSpillStartIndex(gap_index);
838 // This move to spill operand is not a real use. Liveness analysis
839 // and splitting of live ranges do not account for it.
840 // Thus it should be inserted to a lifetime position corresponding to
841 // the instruction end.
842 LGap* gap = GapAt(gap_index);
843 LParallelMove* move = gap->GetOrCreateParallelMove(LGap::BEFORE,
845 move->AddMove(first_output, range->GetSpillOperand(),
850 // Handle fixed input operands of second instruction.
851 if (second != NULL) {
852 for (UseIterator it(second); !it.Done(); it.Advance()) {
853 LUnallocated* cur_input = LUnallocated::cast(it.Current());
854 if (cur_input->HasFixedPolicy()) {
855 LUnallocated* input_copy = cur_input->CopyUnconstrained(
857 bool is_tagged = HasTaggedValue(cur_input->virtual_register());
858 AllocateFixed(cur_input, gap_index + 1, is_tagged);
859 AddConstraintsGapMove(gap_index, input_copy, cur_input);
860 } else if (cur_input->HasWritableRegisterPolicy()) {
861 // The live range of writable input registers always goes until the end
862 // of the instruction.
863 ASSERT(!cur_input->IsUsedAtStart());
865 LUnallocated* input_copy = cur_input->CopyUnconstrained(
867 int vreg = GetVirtualRegister();
868 if (!AllocationOk()) return;
869 cur_input->set_virtual_register(vreg);
871 if (RequiredRegisterKind(input_copy->virtual_register()) ==
873 double_artificial_registers_.Add(
874 cur_input->virtual_register() - first_artificial_register_,
878 AddConstraintsGapMove(gap_index, input_copy, cur_input);
883 // Handle "output same as input" for second instruction.
884 if (second != NULL && second->Output() != NULL) {
885 LUnallocated* second_output = LUnallocated::cast(second->Output());
886 if (second_output->HasSameAsInputPolicy()) {
887 LUnallocated* cur_input = LUnallocated::cast(second->FirstInput());
888 int output_vreg = second_output->virtual_register();
889 int input_vreg = cur_input->virtual_register();
891 LUnallocated* input_copy = cur_input->CopyUnconstrained(
893 cur_input->set_virtual_register(second_output->virtual_register());
894 AddConstraintsGapMove(gap_index, input_copy, cur_input);
896 if (HasTaggedValue(input_vreg) && !HasTaggedValue(output_vreg)) {
897 int index = gap_index + 1;
898 LInstruction* instr = InstructionAt(index);
899 if (instr->HasPointerMap()) {
900 instr->pointer_map()->RecordPointer(input_copy, chunk()->zone());
902 } else if (!HasTaggedValue(input_vreg) && HasTaggedValue(output_vreg)) {
903 // The input is assumed to immediately have a tagged representation,
904 // before the pointer map can be used. I.e. the pointer map at the
905 // instruction will include the output operand (whose value at the
906 // beginning of the instruction is equal to the input operand). If
907 // this is not desired, then the pointer map at this instruction needs
908 // to be adjusted manually.
915 void LAllocator::ProcessInstructions(HBasicBlock* block, BitVector* live) {
916 int block_start = block->first_instruction_index();
917 int index = block->last_instruction_index();
919 LifetimePosition block_start_position =
920 LifetimePosition::FromInstructionIndex(block_start);
922 while (index >= block_start) {
923 LifetimePosition curr_position =
924 LifetimePosition::FromInstructionIndex(index);
926 if (IsGapAt(index)) {
927 // We have a gap at this position.
928 LGap* gap = GapAt(index);
929 LParallelMove* move = gap->GetOrCreateParallelMove(LGap::START,
931 const ZoneList<LMoveOperands>* move_operands = move->move_operands();
932 for (int i = 0; i < move_operands->length(); ++i) {
933 LMoveOperands* cur = &move_operands->at(i);
934 if (cur->IsIgnored()) continue;
935 LOperand* from = cur->source();
936 LOperand* to = cur->destination();
937 HPhi* phi = LookupPhi(to);
940 // This is a phi resolving move.
941 if (!phi->block()->IsLoopHeader()) {
942 hint = LiveRangeFor(phi->id())->current_hint_operand();
945 if (to->IsUnallocated()) {
946 if (live->Contains(LUnallocated::cast(to)->virtual_register())) {
947 Define(curr_position, to, from);
948 live->Remove(LUnallocated::cast(to)->virtual_register());
954 Define(curr_position, to, from);
957 Use(block_start_position, curr_position, from, hint);
958 if (from->IsUnallocated()) {
959 live->Add(LUnallocated::cast(from)->virtual_register());
963 ASSERT(!IsGapAt(index));
964 LInstruction* instr = InstructionAt(index);
967 LOperand* output = instr->Output();
968 if (output != NULL) {
969 if (output->IsUnallocated()) {
970 live->Remove(LUnallocated::cast(output)->virtual_register());
972 Define(curr_position, output, NULL);
975 if (instr->ClobbersRegisters()) {
976 for (int i = 0; i < Register::kMaxNumAllocatableRegisters; ++i) {
977 if (output == NULL || !output->IsRegister() ||
978 output->index() != i) {
979 LiveRange* range = FixedLiveRangeFor(i);
980 range->AddUseInterval(curr_position,
981 curr_position.InstructionEnd(),
987 if (instr->ClobbersDoubleRegisters()) {
988 for (int i = 0; i < DoubleRegister::NumAllocatableRegisters(); ++i) {
989 if (output == NULL || !output->IsDoubleRegister() ||
990 output->index() != i) {
991 LiveRange* range = FixedDoubleLiveRangeFor(i);
992 range->AddUseInterval(curr_position,
993 curr_position.InstructionEnd(),
999 for (UseIterator it(instr); !it.Done(); it.Advance()) {
1000 LOperand* input = it.Current();
1002 LifetimePosition use_pos;
1003 if (input->IsUnallocated() &&
1004 LUnallocated::cast(input)->IsUsedAtStart()) {
1005 use_pos = curr_position;
1007 use_pos = curr_position.InstructionEnd();
1010 Use(block_start_position, use_pos, input, NULL);
1011 if (input->IsUnallocated()) {
1012 live->Add(LUnallocated::cast(input)->virtual_register());
1016 for (TempIterator it(instr); !it.Done(); it.Advance()) {
1017 LOperand* temp = it.Current();
1018 if (instr->ClobbersTemps()) {
1019 if (temp->IsRegister()) continue;
1020 if (temp->IsUnallocated()) {
1021 LUnallocated* temp_unalloc = LUnallocated::cast(temp);
1022 if (temp_unalloc->HasFixedPolicy()) {
1027 Use(block_start_position, curr_position.InstructionEnd(), temp, NULL);
1028 Define(curr_position, temp, NULL);
1038 void LAllocator::ResolvePhis(HBasicBlock* block) {
1039 const ZoneList<HPhi*>* phis = block->phis();
1040 for (int i = 0; i < phis->length(); ++i) {
1041 HPhi* phi = phis->at(i);
1042 LUnallocated* phi_operand =
1043 new(chunk()->zone()) LUnallocated(LUnallocated::NONE);
1044 phi_operand->set_virtual_register(phi->id());
1045 for (int j = 0; j < phi->OperandCount(); ++j) {
1046 HValue* op = phi->OperandAt(j);
1047 LOperand* operand = NULL;
1048 if (op->IsConstant() && op->EmitAtUses()) {
1049 HConstant* constant = HConstant::cast(op);
1050 operand = chunk_->DefineConstantOperand(constant);
1052 ASSERT(!op->EmitAtUses());
1053 LUnallocated* unalloc =
1054 new(chunk()->zone()) LUnallocated(LUnallocated::ANY);
1055 unalloc->set_virtual_register(op->id());
1058 HBasicBlock* cur_block = block->predecessors()->at(j);
1059 // The gap move must be added without any special processing as in
1060 // the AddConstraintsGapMove.
1061 chunk_->AddGapMove(cur_block->last_instruction_index() - 1,
1065 // We are going to insert a move before the branch instruction.
1066 // Some branch instructions (e.g. loops' back edges)
1067 // can potentially cause a GC so they have a pointer map.
1068 // By inserting a move we essentially create a copy of a
1069 // value which is invisible to PopulatePointerMaps(), because we store
1070 // it into a location different from the operand of a live range
1071 // covering a branch instruction.
1072 // Thus we need to manually record a pointer.
1073 LInstruction* branch =
1074 InstructionAt(cur_block->last_instruction_index());
1075 if (branch->HasPointerMap()) {
1076 if (phi->representation().IsTagged() && !phi->type().IsSmi()) {
1077 branch->pointer_map()->RecordPointer(phi_operand, chunk()->zone());
1078 } else if (!phi->representation().IsDouble()) {
1079 branch->pointer_map()->RecordUntagged(phi_operand, chunk()->zone());
1084 LiveRange* live_range = LiveRangeFor(phi->id());
1085 LLabel* label = chunk_->GetLabel(phi->block()->block_id());
1086 label->GetOrCreateParallelMove(LGap::START, chunk()->zone())->
1087 AddMove(phi_operand, live_range->GetSpillOperand(), chunk()->zone());
1088 live_range->SetSpillStartIndex(phi->block()->first_instruction_index());
1093 bool LAllocator::Allocate(LChunk* chunk) {
1094 ASSERT(chunk_ == NULL);
1095 chunk_ = static_cast<LPlatformChunk*>(chunk);
1096 assigned_registers_ =
1097 new(chunk->zone()) BitVector(Register::NumAllocatableRegisters(),
1099 assigned_double_registers_ =
1100 new(chunk->zone()) BitVector(DoubleRegister::NumAllocatableRegisters(),
1102 MeetRegisterConstraints();
1103 if (!AllocationOk()) return false;
1106 AllocateGeneralRegisters();
1107 if (!AllocationOk()) return false;
1108 AllocateDoubleRegisters();
1109 if (!AllocationOk()) return false;
1110 PopulatePointerMaps();
1112 ResolveControlFlow();
1117 void LAllocator::MeetRegisterConstraints() {
1118 LAllocatorPhase phase("L_Register constraints", this);
1119 first_artificial_register_ = next_virtual_register_;
1120 const ZoneList<HBasicBlock*>* blocks = graph_->blocks();
1121 for (int i = 0; i < blocks->length(); ++i) {
1122 HBasicBlock* block = blocks->at(i);
1123 MeetRegisterConstraints(block);
1124 if (!AllocationOk()) return;
1129 void LAllocator::ResolvePhis() {
1130 LAllocatorPhase phase("L_Resolve phis", this);
1132 // Process the blocks in reverse order.
1133 const ZoneList<HBasicBlock*>* blocks = graph_->blocks();
1134 for (int block_id = blocks->length() - 1; block_id >= 0; --block_id) {
1135 HBasicBlock* block = blocks->at(block_id);
1141 void LAllocator::ResolveControlFlow(LiveRange* range,
1143 HBasicBlock* pred) {
1144 LifetimePosition pred_end =
1145 LifetimePosition::FromInstructionIndex(pred->last_instruction_index());
1146 LifetimePosition cur_start =
1147 LifetimePosition::FromInstructionIndex(block->first_instruction_index());
1148 LiveRange* pred_cover = NULL;
1149 LiveRange* cur_cover = NULL;
1150 LiveRange* cur_range = range;
1151 while (cur_range != NULL && (cur_cover == NULL || pred_cover == NULL)) {
1152 if (cur_range->CanCover(cur_start)) {
1153 ASSERT(cur_cover == NULL);
1154 cur_cover = cur_range;
1156 if (cur_range->CanCover(pred_end)) {
1157 ASSERT(pred_cover == NULL);
1158 pred_cover = cur_range;
1160 cur_range = cur_range->next();
1163 if (cur_cover->IsSpilled()) return;
1164 ASSERT(pred_cover != NULL && cur_cover != NULL);
1165 if (pred_cover != cur_cover) {
1166 LOperand* pred_op = pred_cover->CreateAssignedOperand(chunk()->zone());
1167 LOperand* cur_op = cur_cover->CreateAssignedOperand(chunk()->zone());
1168 if (!pred_op->Equals(cur_op)) {
1170 if (block->predecessors()->length() == 1) {
1171 gap = GapAt(block->first_instruction_index());
1173 ASSERT(pred->end()->SecondSuccessor() == NULL);
1174 gap = GetLastGap(pred);
1176 // We are going to insert a move before the branch instruction.
1177 // Some branch instructions (e.g. loops' back edges)
1178 // can potentially cause a GC so they have a pointer map.
1179 // By inserting a move we essentially create a copy of a
1180 // value which is invisible to PopulatePointerMaps(), because we store
1181 // it into a location different from the operand of a live range
1182 // covering a branch instruction.
1183 // Thus we need to manually record a pointer.
1184 LInstruction* branch = InstructionAt(pred->last_instruction_index());
1185 if (branch->HasPointerMap()) {
1186 if (HasTaggedValue(range->id())) {
1187 branch->pointer_map()->RecordPointer(cur_op, chunk()->zone());
1188 } else if (!cur_op->IsDoubleStackSlot() &&
1189 !cur_op->IsDoubleRegister()) {
1190 branch->pointer_map()->RemovePointer(cur_op);
1194 gap->GetOrCreateParallelMove(
1195 LGap::START, chunk()->zone())->AddMove(pred_op, cur_op,
1202 LParallelMove* LAllocator::GetConnectingParallelMove(LifetimePosition pos) {
1203 int index = pos.InstructionIndex();
1204 if (IsGapAt(index)) {
1205 LGap* gap = GapAt(index);
1206 return gap->GetOrCreateParallelMove(
1207 pos.IsInstructionStart() ? LGap::START : LGap::END, chunk()->zone());
1209 int gap_pos = pos.IsInstructionStart() ? (index - 1) : (index + 1);
1210 return GapAt(gap_pos)->GetOrCreateParallelMove(
1211 (gap_pos < index) ? LGap::AFTER : LGap::BEFORE, chunk()->zone());
1215 HBasicBlock* LAllocator::GetBlock(LifetimePosition pos) {
1216 LGap* gap = GapAt(chunk_->NearestGapPos(pos.InstructionIndex()));
1217 return gap->block();
1221 void LAllocator::ConnectRanges() {
1222 LAllocatorPhase phase("L_Connect ranges", this);
1223 for (int i = 0; i < live_ranges()->length(); ++i) {
1224 LiveRange* first_range = live_ranges()->at(i);
1225 if (first_range == NULL || first_range->parent() != NULL) continue;
1227 LiveRange* second_range = first_range->next();
1228 while (second_range != NULL) {
1229 LifetimePosition pos = second_range->Start();
1231 if (!second_range->IsSpilled()) {
1232 // Add gap move if the two live ranges touch and there is no block
1234 if (first_range->End().Value() == pos.Value()) {
1235 bool should_insert = true;
1236 if (IsBlockBoundary(pos)) {
1237 should_insert = CanEagerlyResolveControlFlow(GetBlock(pos));
1239 if (should_insert) {
1240 LParallelMove* move = GetConnectingParallelMove(pos);
1241 LOperand* prev_operand = first_range->CreateAssignedOperand(
1243 LOperand* cur_operand = second_range->CreateAssignedOperand(
1245 move->AddMove(prev_operand, cur_operand,
1251 first_range = second_range;
1252 second_range = second_range->next();
1258 bool LAllocator::CanEagerlyResolveControlFlow(HBasicBlock* block) const {
1259 if (block->predecessors()->length() != 1) return false;
1260 return block->predecessors()->first()->block_id() == block->block_id() - 1;
1264 void LAllocator::ResolveControlFlow() {
1265 LAllocatorPhase phase("L_Resolve control flow", this);
1266 const ZoneList<HBasicBlock*>* blocks = graph_->blocks();
1267 for (int block_id = 1; block_id < blocks->length(); ++block_id) {
1268 HBasicBlock* block = blocks->at(block_id);
1269 if (CanEagerlyResolveControlFlow(block)) continue;
1270 BitVector* live = live_in_sets_[block->block_id()];
1271 BitVector::Iterator iterator(live);
1272 while (!iterator.Done()) {
1273 int operand_index = iterator.Current();
1274 for (int i = 0; i < block->predecessors()->length(); ++i) {
1275 HBasicBlock* cur = block->predecessors()->at(i);
1276 LiveRange* cur_range = LiveRangeFor(operand_index);
1277 ResolveControlFlow(cur_range, block, cur);
1285 void LAllocator::BuildLiveRanges() {
1286 LAllocatorPhase phase("L_Build live ranges", this);
1287 InitializeLivenessAnalysis();
1288 // Process the blocks in reverse order.
1289 const ZoneList<HBasicBlock*>* blocks = graph_->blocks();
1290 for (int block_id = blocks->length() - 1; block_id >= 0; --block_id) {
1291 HBasicBlock* block = blocks->at(block_id);
1292 BitVector* live = ComputeLiveOut(block);
1293 // Initially consider all live_out values live for the entire block. We
1294 // will shorten these intervals if necessary.
1295 AddInitialIntervals(block, live);
1297 // Process the instructions in reverse order, generating and killing
1299 ProcessInstructions(block, live);
1300 // All phi output operands are killed by this block.
1301 const ZoneList<HPhi*>* phis = block->phis();
1302 for (int i = 0; i < phis->length(); ++i) {
1303 // The live range interval already ends at the first instruction of the
1305 HPhi* phi = phis->at(i);
1306 live->Remove(phi->id());
1308 LOperand* hint = NULL;
1309 LOperand* phi_operand = NULL;
1310 LGap* gap = GetLastGap(phi->block()->predecessors()->at(0));
1311 LParallelMove* move = gap->GetOrCreateParallelMove(LGap::START,
1313 for (int j = 0; j < move->move_operands()->length(); ++j) {
1314 LOperand* to = move->move_operands()->at(j).destination();
1315 if (to->IsUnallocated() &&
1316 LUnallocated::cast(to)->virtual_register() == phi->id()) {
1317 hint = move->move_operands()->at(j).source();
1322 ASSERT(hint != NULL);
1324 LifetimePosition block_start = LifetimePosition::FromInstructionIndex(
1325 block->first_instruction_index());
1326 Define(block_start, phi_operand, hint);
1329 // Now live is live_in for this block except not including values live
1330 // out on backward successor edges.
1331 live_in_sets_[block_id] = live;
1333 // If this block is a loop header go back and patch up the necessary
1334 // predecessor blocks.
1335 if (block->IsLoopHeader()) {
1336 // TODO(kmillikin): Need to be able to get the last block of the loop
1337 // in the loop information. Add a live range stretching from the first
1338 // loop instruction to the last for each value live on entry to the
1340 HBasicBlock* back_edge = block->loop_information()->GetLastBackEdge();
1341 BitVector::Iterator iterator(live);
1342 LifetimePosition start = LifetimePosition::FromInstructionIndex(
1343 block->first_instruction_index());
1344 LifetimePosition end = LifetimePosition::FromInstructionIndex(
1345 back_edge->last_instruction_index()).NextInstruction();
1346 while (!iterator.Done()) {
1347 int operand_index = iterator.Current();
1348 LiveRange* range = LiveRangeFor(operand_index);
1349 range->EnsureInterval(start, end, zone());
1353 for (int i = block->block_id() + 1; i <= back_edge->block_id(); ++i) {
1354 live_in_sets_[i]->Union(*live);
1359 if (block_id == 0) {
1360 BitVector::Iterator iterator(live);
1362 while (!iterator.Done()) {
1364 int operand_index = iterator.Current();
1365 if (chunk_->info()->IsStub()) {
1366 CodeStub::Major major_key = chunk_->info()->code_stub()->MajorKey();
1367 PrintF("Function: %s\n", CodeStub::MajorName(major_key, false));
1369 ASSERT(chunk_->info()->IsOptimizing());
1370 AllowHandleDereference allow_deref;
1371 PrintF("Function: %s\n",
1372 *chunk_->info()->function()->debug_name()->ToCString());
1374 PrintF("Value %d used before first definition!\n", operand_index);
1375 LiveRange* range = LiveRangeFor(operand_index);
1376 PrintF("First use is at %d\n", range->first_pos()->pos().Value());
1384 for (int i = 0; i < live_ranges_.length(); ++i) {
1385 if (live_ranges_[i] != NULL) {
1386 live_ranges_[i]->kind_ = RequiredRegisterKind(live_ranges_[i]->id());
1392 bool LAllocator::SafePointsAreInOrder() const {
1393 const ZoneList<LPointerMap*>* pointer_maps = chunk_->pointer_maps();
1395 for (int i = 0; i < pointer_maps->length(); ++i) {
1396 LPointerMap* map = pointer_maps->at(i);
1397 if (safe_point > map->lithium_position()) return false;
1398 safe_point = map->lithium_position();
1404 void LAllocator::PopulatePointerMaps() {
1405 LAllocatorPhase phase("L_Populate pointer maps", this);
1406 const ZoneList<LPointerMap*>* pointer_maps = chunk_->pointer_maps();
1408 ASSERT(SafePointsAreInOrder());
1410 // Iterate over all safe point positions and record a pointer
1411 // for all spilled live ranges at this point.
1412 int first_safe_point_index = 0;
1413 int last_range_start = 0;
1414 for (int range_idx = 0; range_idx < live_ranges()->length(); ++range_idx) {
1415 LiveRange* range = live_ranges()->at(range_idx);
1416 if (range == NULL) continue;
1417 // Iterate over the first parts of multi-part live ranges.
1418 if (range->parent() != NULL) continue;
1419 // Skip non-pointer values.
1420 if (!HasTaggedValue(range->id())) continue;
1421 // Skip empty live ranges.
1422 if (range->IsEmpty()) continue;
1424 // Find the extent of the range and its children.
1425 int start = range->Start().InstructionIndex();
1427 for (LiveRange* cur = range; cur != NULL; cur = cur->next()) {
1428 LifetimePosition this_end = cur->End();
1429 if (this_end.InstructionIndex() > end) end = this_end.InstructionIndex();
1430 ASSERT(cur->Start().InstructionIndex() >= start);
1433 // Most of the ranges are in order, but not all. Keep an eye on when
1434 // they step backwards and reset the first_safe_point_index so we don't
1435 // miss any safe points.
1436 if (start < last_range_start) {
1437 first_safe_point_index = 0;
1439 last_range_start = start;
1441 // Step across all the safe points that are before the start of this range,
1442 // recording how far we step in order to save doing this for the next range.
1443 while (first_safe_point_index < pointer_maps->length()) {
1444 LPointerMap* map = pointer_maps->at(first_safe_point_index);
1445 int safe_point = map->lithium_position();
1446 if (safe_point >= start) break;
1447 first_safe_point_index++;
1450 // Step through the safe points to see whether they are in the range.
1451 for (int safe_point_index = first_safe_point_index;
1452 safe_point_index < pointer_maps->length();
1453 ++safe_point_index) {
1454 LPointerMap* map = pointer_maps->at(safe_point_index);
1455 int safe_point = map->lithium_position();
1457 // The safe points are sorted so we can stop searching here.
1458 if (safe_point - 1 > end) break;
1460 // Advance to the next active range that covers the current
1461 // safe point position.
1462 LifetimePosition safe_point_pos =
1463 LifetimePosition::FromInstructionIndex(safe_point);
1464 LiveRange* cur = range;
1465 while (cur != NULL && !cur->Covers(safe_point_pos)) {
1468 if (cur == NULL) continue;
1470 // Check if the live range is spilled and the safe point is after
1471 // the spill position.
1472 if (range->HasAllocatedSpillOperand() &&
1473 safe_point >= range->spill_start_index()) {
1474 TraceAlloc("Pointer for range %d (spilled at %d) at safe point %d\n",
1475 range->id(), range->spill_start_index(), safe_point);
1476 map->RecordPointer(range->GetSpillOperand(), chunk()->zone());
1479 if (!cur->IsSpilled()) {
1480 TraceAlloc("Pointer in register for range %d (start at %d) "
1481 "at safe point %d\n",
1482 cur->id(), cur->Start().Value(), safe_point);
1483 LOperand* operand = cur->CreateAssignedOperand(chunk()->zone());
1484 ASSERT(!operand->IsStackSlot());
1485 map->RecordPointer(operand, chunk()->zone());
1492 void LAllocator::AllocateGeneralRegisters() {
1493 LAllocatorPhase phase("L_Allocate general registers", this);
1494 num_registers_ = Register::NumAllocatableRegisters();
1495 mode_ = GENERAL_REGISTERS;
1496 AllocateRegisters();
1500 void LAllocator::AllocateDoubleRegisters() {
1501 LAllocatorPhase phase("L_Allocate double registers", this);
1502 num_registers_ = DoubleRegister::NumAllocatableRegisters();
1503 mode_ = DOUBLE_REGISTERS;
1504 AllocateRegisters();
1508 void LAllocator::AllocateRegisters() {
1509 ASSERT(unhandled_live_ranges_.is_empty());
1511 for (int i = 0; i < live_ranges_.length(); ++i) {
1512 if (live_ranges_[i] != NULL) {
1513 if (live_ranges_[i]->Kind() == mode_) {
1514 AddToUnhandledUnsorted(live_ranges_[i]);
1519 ASSERT(UnhandledIsSorted());
1521 ASSERT(reusable_slots_.is_empty());
1522 ASSERT(active_live_ranges_.is_empty());
1523 ASSERT(inactive_live_ranges_.is_empty());
1525 if (mode_ == DOUBLE_REGISTERS) {
1526 for (int i = 0; i < DoubleRegister::NumAllocatableRegisters(); ++i) {
1527 LiveRange* current = fixed_double_live_ranges_.at(i);
1528 if (current != NULL) {
1529 AddToInactive(current);
1533 ASSERT(mode_ == GENERAL_REGISTERS);
1534 for (int i = 0; i < fixed_live_ranges_.length(); ++i) {
1535 LiveRange* current = fixed_live_ranges_.at(i);
1536 if (current != NULL) {
1537 AddToInactive(current);
1542 while (!unhandled_live_ranges_.is_empty()) {
1543 ASSERT(UnhandledIsSorted());
1544 LiveRange* current = unhandled_live_ranges_.RemoveLast();
1545 ASSERT(UnhandledIsSorted());
1546 LifetimePosition position = current->Start();
1548 allocation_finger_ = position;
1550 TraceAlloc("Processing interval %d start=%d\n",
1554 if (current->HasAllocatedSpillOperand()) {
1555 TraceAlloc("Live range %d already has a spill operand\n", current->id());
1556 LifetimePosition next_pos = position;
1557 if (IsGapAt(next_pos.InstructionIndex())) {
1558 next_pos = next_pos.NextInstruction();
1560 UsePosition* pos = current->NextUsePositionRegisterIsBeneficial(next_pos);
1561 // If the range already has a spill operand and it doesn't need a
1562 // register immediately, split it and spill the first part of the range.
1566 } else if (pos->pos().Value() >
1567 current->Start().NextInstruction().Value()) {
1568 // Do not spill live range eagerly if use position that can benefit from
1569 // the register is too close to the start of live range.
1570 SpillBetween(current, current->Start(), pos->pos());
1571 if (!AllocationOk()) return;
1572 ASSERT(UnhandledIsSorted());
1577 for (int i = 0; i < active_live_ranges_.length(); ++i) {
1578 LiveRange* cur_active = active_live_ranges_.at(i);
1579 if (cur_active->End().Value() <= position.Value()) {
1580 ActiveToHandled(cur_active);
1581 --i; // The live range was removed from the list of active live ranges.
1582 } else if (!cur_active->Covers(position)) {
1583 ActiveToInactive(cur_active);
1584 --i; // The live range was removed from the list of active live ranges.
1588 for (int i = 0; i < inactive_live_ranges_.length(); ++i) {
1589 LiveRange* cur_inactive = inactive_live_ranges_.at(i);
1590 if (cur_inactive->End().Value() <= position.Value()) {
1591 InactiveToHandled(cur_inactive);
1592 --i; // Live range was removed from the list of inactive live ranges.
1593 } else if (cur_inactive->Covers(position)) {
1594 InactiveToActive(cur_inactive);
1595 --i; // Live range was removed from the list of inactive live ranges.
1599 ASSERT(!current->HasRegisterAssigned() && !current->IsSpilled());
1601 bool result = TryAllocateFreeReg(current);
1602 if (!AllocationOk()) return;
1604 if (!result) AllocateBlockedReg(current);
1605 if (!AllocationOk()) return;
1607 if (current->HasRegisterAssigned()) {
1608 AddToActive(current);
1612 reusable_slots_.Rewind(0);
1613 active_live_ranges_.Rewind(0);
1614 inactive_live_ranges_.Rewind(0);
1618 const char* LAllocator::RegisterName(int allocation_index) {
1619 if (mode_ == GENERAL_REGISTERS) {
1620 return Register::AllocationIndexToString(allocation_index);
1622 return DoubleRegister::AllocationIndexToString(allocation_index);
1627 void LAllocator::TraceAlloc(const char* msg, ...) {
1628 if (FLAG_trace_alloc) {
1630 va_start(arguments, msg);
1631 OS::VPrint(msg, arguments);
1637 bool LAllocator::HasTaggedValue(int virtual_register) const {
1638 HValue* value = graph_->LookupValue(virtual_register);
1639 if (value == NULL) return false;
1640 return value->representation().IsTagged() && !value->type().IsSmi();
1644 RegisterKind LAllocator::RequiredRegisterKind(int virtual_register) const {
1645 if (virtual_register < first_artificial_register_) {
1646 HValue* value = graph_->LookupValue(virtual_register);
1647 if (value != NULL && value->representation().IsDouble()) {
1648 return DOUBLE_REGISTERS;
1650 } else if (double_artificial_registers_.Contains(
1651 virtual_register - first_artificial_register_)) {
1652 return DOUBLE_REGISTERS;
1655 return GENERAL_REGISTERS;
1659 void LAllocator::AddToActive(LiveRange* range) {
1660 TraceAlloc("Add live range %d to active\n", range->id());
1661 active_live_ranges_.Add(range, zone());
1665 void LAllocator::AddToInactive(LiveRange* range) {
1666 TraceAlloc("Add live range %d to inactive\n", range->id());
1667 inactive_live_ranges_.Add(range, zone());
1671 void LAllocator::AddToUnhandledSorted(LiveRange* range) {
1672 if (range == NULL || range->IsEmpty()) return;
1673 ASSERT(!range->HasRegisterAssigned() && !range->IsSpilled());
1674 ASSERT(allocation_finger_.Value() <= range->Start().Value());
1675 for (int i = unhandled_live_ranges_.length() - 1; i >= 0; --i) {
1676 LiveRange* cur_range = unhandled_live_ranges_.at(i);
1677 if (range->ShouldBeAllocatedBefore(cur_range)) {
1678 TraceAlloc("Add live range %d to unhandled at %d\n", range->id(), i + 1);
1679 unhandled_live_ranges_.InsertAt(i + 1, range, zone());
1680 ASSERT(UnhandledIsSorted());
1684 TraceAlloc("Add live range %d to unhandled at start\n", range->id());
1685 unhandled_live_ranges_.InsertAt(0, range, zone());
1686 ASSERT(UnhandledIsSorted());
1690 void LAllocator::AddToUnhandledUnsorted(LiveRange* range) {
1691 if (range == NULL || range->IsEmpty()) return;
1692 ASSERT(!range->HasRegisterAssigned() && !range->IsSpilled());
1693 TraceAlloc("Add live range %d to unhandled unsorted at end\n", range->id());
1694 unhandled_live_ranges_.Add(range, zone());
1698 static int UnhandledSortHelper(LiveRange* const* a, LiveRange* const* b) {
1699 ASSERT(!(*a)->ShouldBeAllocatedBefore(*b) ||
1700 !(*b)->ShouldBeAllocatedBefore(*a));
1701 if ((*a)->ShouldBeAllocatedBefore(*b)) return 1;
1702 if ((*b)->ShouldBeAllocatedBefore(*a)) return -1;
1703 return (*a)->id() - (*b)->id();
1707 // Sort the unhandled live ranges so that the ranges to be processed first are
1708 // at the end of the array list. This is convenient for the register allocation
1709 // algorithm because it is efficient to remove elements from the end.
1710 void LAllocator::SortUnhandled() {
1711 TraceAlloc("Sort unhandled\n");
1712 unhandled_live_ranges_.Sort(&UnhandledSortHelper);
1716 bool LAllocator::UnhandledIsSorted() {
1717 int len = unhandled_live_ranges_.length();
1718 for (int i = 1; i < len; i++) {
1719 LiveRange* a = unhandled_live_ranges_.at(i - 1);
1720 LiveRange* b = unhandled_live_ranges_.at(i);
1721 if (a->Start().Value() < b->Start().Value()) return false;
1727 void LAllocator::FreeSpillSlot(LiveRange* range) {
1728 // Check that we are the last range.
1729 if (range->next() != NULL) return;
1731 if (!range->TopLevel()->HasAllocatedSpillOperand()) return;
1733 int index = range->TopLevel()->GetSpillOperand()->index();
1735 reusable_slots_.Add(range, zone());
1740 LOperand* LAllocator::TryReuseSpillSlot(LiveRange* range) {
1741 if (reusable_slots_.is_empty()) return NULL;
1742 if (reusable_slots_.first()->End().Value() >
1743 range->TopLevel()->Start().Value()) {
1746 LOperand* result = reusable_slots_.first()->TopLevel()->GetSpillOperand();
1747 reusable_slots_.Remove(0);
1752 void LAllocator::ActiveToHandled(LiveRange* range) {
1753 ASSERT(active_live_ranges_.Contains(range));
1754 active_live_ranges_.RemoveElement(range);
1755 TraceAlloc("Moving live range %d from active to handled\n", range->id());
1756 FreeSpillSlot(range);
1760 void LAllocator::ActiveToInactive(LiveRange* range) {
1761 ASSERT(active_live_ranges_.Contains(range));
1762 active_live_ranges_.RemoveElement(range);
1763 inactive_live_ranges_.Add(range, zone());
1764 TraceAlloc("Moving live range %d from active to inactive\n", range->id());
1768 void LAllocator::InactiveToHandled(LiveRange* range) {
1769 ASSERT(inactive_live_ranges_.Contains(range));
1770 inactive_live_ranges_.RemoveElement(range);
1771 TraceAlloc("Moving live range %d from inactive to handled\n", range->id());
1772 FreeSpillSlot(range);
1776 void LAllocator::InactiveToActive(LiveRange* range) {
1777 ASSERT(inactive_live_ranges_.Contains(range));
1778 inactive_live_ranges_.RemoveElement(range);
1779 active_live_ranges_.Add(range, zone());
1780 TraceAlloc("Moving live range %d from inactive to active\n", range->id());
1784 // TryAllocateFreeReg and AllocateBlockedReg assume this
1785 // when allocating local arrays.
1786 STATIC_ASSERT(DoubleRegister::kMaxNumAllocatableRegisters >=
1787 Register::kMaxNumAllocatableRegisters);
1790 bool LAllocator::TryAllocateFreeReg(LiveRange* current) {
1791 LifetimePosition free_until_pos[DoubleRegister::kMaxNumAllocatableRegisters];
1793 for (int i = 0; i < num_registers_; i++) {
1794 free_until_pos[i] = LifetimePosition::MaxPosition();
1797 for (int i = 0; i < active_live_ranges_.length(); ++i) {
1798 LiveRange* cur_active = active_live_ranges_.at(i);
1799 free_until_pos[cur_active->assigned_register()] =
1800 LifetimePosition::FromInstructionIndex(0);
1803 for (int i = 0; i < inactive_live_ranges_.length(); ++i) {
1804 LiveRange* cur_inactive = inactive_live_ranges_.at(i);
1805 ASSERT(cur_inactive->End().Value() > current->Start().Value());
1806 LifetimePosition next_intersection =
1807 cur_inactive->FirstIntersection(current);
1808 if (!next_intersection.IsValid()) continue;
1809 int cur_reg = cur_inactive->assigned_register();
1810 free_until_pos[cur_reg] = Min(free_until_pos[cur_reg], next_intersection);
1813 LOperand* hint = current->FirstHint();
1814 if (hint != NULL && (hint->IsRegister() || hint->IsDoubleRegister())) {
1815 int register_index = hint->index();
1817 "Found reg hint %s (free until [%d) for live range %d (end %d[).\n",
1818 RegisterName(register_index),
1819 free_until_pos[register_index].Value(),
1821 current->End().Value());
1823 // The desired register is free until the end of the current live range.
1824 if (free_until_pos[register_index].Value() >= current->End().Value()) {
1825 TraceAlloc("Assigning preferred reg %s to live range %d\n",
1826 RegisterName(register_index),
1828 SetLiveRangeAssignedRegister(current, register_index);
1833 // Find the register which stays free for the longest time.
1835 for (int i = 1; i < RegisterCount(); ++i) {
1836 if (free_until_pos[i].Value() > free_until_pos[reg].Value()) {
1841 LifetimePosition pos = free_until_pos[reg];
1843 if (pos.Value() <= current->Start().Value()) {
1844 // All registers are blocked.
1848 if (pos.Value() < current->End().Value()) {
1849 // Register reg is available at the range start but becomes blocked before
1850 // the range end. Split current at position where it becomes blocked.
1851 LiveRange* tail = SplitRangeAt(current, pos);
1852 if (!AllocationOk()) return false;
1853 AddToUnhandledSorted(tail);
1857 // Register reg is available at the range start and is free until
1859 ASSERT(pos.Value() >= current->End().Value());
1860 TraceAlloc("Assigning free reg %s to live range %d\n",
1863 SetLiveRangeAssignedRegister(current, reg);
1869 void LAllocator::AllocateBlockedReg(LiveRange* current) {
1870 UsePosition* register_use = current->NextRegisterPosition(current->Start());
1871 if (register_use == NULL) {
1872 // There is no use in the current live range that requires a register.
1873 // We can just spill it.
1879 LifetimePosition use_pos[DoubleRegister::kMaxNumAllocatableRegisters];
1880 LifetimePosition block_pos[DoubleRegister::kMaxNumAllocatableRegisters];
1882 for (int i = 0; i < num_registers_; i++) {
1883 use_pos[i] = block_pos[i] = LifetimePosition::MaxPosition();
1886 for (int i = 0; i < active_live_ranges_.length(); ++i) {
1887 LiveRange* range = active_live_ranges_[i];
1888 int cur_reg = range->assigned_register();
1889 if (range->IsFixed() || !range->CanBeSpilled(current->Start())) {
1890 block_pos[cur_reg] = use_pos[cur_reg] =
1891 LifetimePosition::FromInstructionIndex(0);
1893 UsePosition* next_use = range->NextUsePositionRegisterIsBeneficial(
1895 if (next_use == NULL) {
1896 use_pos[cur_reg] = range->End();
1898 use_pos[cur_reg] = next_use->pos();
1903 for (int i = 0; i < inactive_live_ranges_.length(); ++i) {
1904 LiveRange* range = inactive_live_ranges_.at(i);
1905 ASSERT(range->End().Value() > current->Start().Value());
1906 LifetimePosition next_intersection = range->FirstIntersection(current);
1907 if (!next_intersection.IsValid()) continue;
1908 int cur_reg = range->assigned_register();
1909 if (range->IsFixed()) {
1910 block_pos[cur_reg] = Min(block_pos[cur_reg], next_intersection);
1911 use_pos[cur_reg] = Min(block_pos[cur_reg], use_pos[cur_reg]);
1913 use_pos[cur_reg] = Min(use_pos[cur_reg], next_intersection);
1918 for (int i = 1; i < RegisterCount(); ++i) {
1919 if (use_pos[i].Value() > use_pos[reg].Value()) {
1924 LifetimePosition pos = use_pos[reg];
1926 if (pos.Value() < register_use->pos().Value()) {
1927 // All registers are blocked before the first use that requires a register.
1928 // Spill starting part of live range up to that use.
1929 SpillBetween(current, current->Start(), register_use->pos());
1933 if (block_pos[reg].Value() < current->End().Value()) {
1934 // Register becomes blocked before the current range end. Split before that
1936 LiveRange* tail = SplitBetween(current,
1938 block_pos[reg].InstructionStart());
1939 if (!AllocationOk()) return;
1940 AddToUnhandledSorted(tail);
1943 // Register reg is not blocked for the whole range.
1944 ASSERT(block_pos[reg].Value() >= current->End().Value());
1945 TraceAlloc("Assigning blocked reg %s to live range %d\n",
1948 SetLiveRangeAssignedRegister(current, reg);
1950 // This register was not free. Thus we need to find and spill
1951 // parts of active and inactive live regions that use the same register
1952 // at the same lifetime positions as current.
1953 SplitAndSpillIntersecting(current);
1957 LifetimePosition LAllocator::FindOptimalSpillingPos(LiveRange* range,
1958 LifetimePosition pos) {
1959 HBasicBlock* block = GetBlock(pos.InstructionStart());
1960 HBasicBlock* loop_header =
1961 block->IsLoopHeader() ? block : block->parent_loop_header();
1963 if (loop_header == NULL) return pos;
1965 UsePosition* prev_use =
1966 range->PreviousUsePositionRegisterIsBeneficial(pos);
1968 while (loop_header != NULL) {
1969 // We are going to spill live range inside the loop.
1970 // If possible try to move spilling position backwards to loop header.
1971 // This will reduce number of memory moves on the back edge.
1972 LifetimePosition loop_start = LifetimePosition::FromInstructionIndex(
1973 loop_header->first_instruction_index());
1975 if (range->Covers(loop_start)) {
1976 if (prev_use == NULL || prev_use->pos().Value() < loop_start.Value()) {
1977 // No register beneficial use inside the loop before the pos.
1982 // Try hoisting out to an outer loop.
1983 loop_header = loop_header->parent_loop_header();
1990 void LAllocator::SplitAndSpillIntersecting(LiveRange* current) {
1991 ASSERT(current->HasRegisterAssigned());
1992 int reg = current->assigned_register();
1993 LifetimePosition split_pos = current->Start();
1994 for (int i = 0; i < active_live_ranges_.length(); ++i) {
1995 LiveRange* range = active_live_ranges_[i];
1996 if (range->assigned_register() == reg) {
1997 UsePosition* next_pos = range->NextRegisterPosition(current->Start());
1998 LifetimePosition spill_pos = FindOptimalSpillingPos(range, split_pos);
1999 if (next_pos == NULL) {
2000 SpillAfter(range, spill_pos);
2002 // When spilling between spill_pos and next_pos ensure that the range
2003 // remains spilled at least until the start of the current live range.
2004 // This guarantees that we will not introduce new unhandled ranges that
2005 // start before the current range as this violates allocation invariant
2006 // and will lead to an inconsistent state of active and inactive
2007 // live-ranges: ranges are allocated in order of their start positions,
2008 // ranges are retired from active/inactive when the start of the
2009 // current live-range is larger than their end.
2010 SpillBetweenUntil(range, spill_pos, current->Start(), next_pos->pos());
2012 if (!AllocationOk()) return;
2013 ActiveToHandled(range);
2018 for (int i = 0; i < inactive_live_ranges_.length(); ++i) {
2019 LiveRange* range = inactive_live_ranges_[i];
2020 ASSERT(range->End().Value() > current->Start().Value());
2021 if (range->assigned_register() == reg && !range->IsFixed()) {
2022 LifetimePosition next_intersection = range->FirstIntersection(current);
2023 if (next_intersection.IsValid()) {
2024 UsePosition* next_pos = range->NextRegisterPosition(current->Start());
2025 if (next_pos == NULL) {
2026 SpillAfter(range, split_pos);
2028 next_intersection = Min(next_intersection, next_pos->pos());
2029 SpillBetween(range, split_pos, next_intersection);
2031 if (!AllocationOk()) return;
2032 InactiveToHandled(range);
2040 bool LAllocator::IsBlockBoundary(LifetimePosition pos) {
2041 return pos.IsInstructionStart() &&
2042 InstructionAt(pos.InstructionIndex())->IsLabel();
2046 LiveRange* LAllocator::SplitRangeAt(LiveRange* range, LifetimePosition pos) {
2047 ASSERT(!range->IsFixed());
2048 TraceAlloc("Splitting live range %d at %d\n", range->id(), pos.Value());
2050 if (pos.Value() <= range->Start().Value()) return range;
2052 // We can't properly connect liveranges if split occured at the end
2053 // of control instruction.
2054 ASSERT(pos.IsInstructionStart() ||
2055 !chunk_->instructions()->at(pos.InstructionIndex())->IsControl());
2057 int vreg = GetVirtualRegister();
2058 if (!AllocationOk()) return NULL;
2059 LiveRange* result = LiveRangeFor(vreg);
2060 range->SplitAt(pos, result, zone());
2065 LiveRange* LAllocator::SplitBetween(LiveRange* range,
2066 LifetimePosition start,
2067 LifetimePosition end) {
2068 ASSERT(!range->IsFixed());
2069 TraceAlloc("Splitting live range %d in position between [%d, %d]\n",
2074 LifetimePosition split_pos = FindOptimalSplitPos(start, end);
2075 ASSERT(split_pos.Value() >= start.Value());
2076 return SplitRangeAt(range, split_pos);
2080 LifetimePosition LAllocator::FindOptimalSplitPos(LifetimePosition start,
2081 LifetimePosition end) {
2082 int start_instr = start.InstructionIndex();
2083 int end_instr = end.InstructionIndex();
2084 ASSERT(start_instr <= end_instr);
2086 // We have no choice
2087 if (start_instr == end_instr) return end;
2089 HBasicBlock* start_block = GetBlock(start);
2090 HBasicBlock* end_block = GetBlock(end);
2092 if (end_block == start_block) {
2093 // The interval is split in the same basic block. Split at the latest
2094 // possible position.
2098 HBasicBlock* block = end_block;
2099 // Find header of outermost loop.
2100 while (block->parent_loop_header() != NULL &&
2101 block->parent_loop_header()->block_id() > start_block->block_id()) {
2102 block = block->parent_loop_header();
2105 // We did not find any suitable outer loop. Split at the latest possible
2106 // position unless end_block is a loop header itself.
2107 if (block == end_block && !end_block->IsLoopHeader()) return end;
2109 return LifetimePosition::FromInstructionIndex(
2110 block->first_instruction_index());
2114 void LAllocator::SpillAfter(LiveRange* range, LifetimePosition pos) {
2115 LiveRange* second_part = SplitRangeAt(range, pos);
2116 if (!AllocationOk()) return;
2121 void LAllocator::SpillBetween(LiveRange* range,
2122 LifetimePosition start,
2123 LifetimePosition end) {
2124 SpillBetweenUntil(range, start, start, end);
2128 void LAllocator::SpillBetweenUntil(LiveRange* range,
2129 LifetimePosition start,
2130 LifetimePosition until,
2131 LifetimePosition end) {
2132 CHECK(start.Value() < end.Value());
2133 LiveRange* second_part = SplitRangeAt(range, start);
2134 if (!AllocationOk()) return;
2136 if (second_part->Start().Value() < end.Value()) {
2137 // The split result intersects with [start, end[.
2138 // Split it at position between ]start+1, end[, spill the middle part
2139 // and put the rest to unhandled.
2140 LiveRange* third_part = SplitBetween(
2142 Max(second_part->Start().InstructionEnd(), until),
2143 end.PrevInstruction().InstructionEnd());
2144 if (!AllocationOk()) return;
2146 ASSERT(third_part != second_part);
2149 AddToUnhandledSorted(third_part);
2151 // The split result does not intersect with [start, end[.
2152 // Nothing to spill. Just put it to unhandled as whole.
2153 AddToUnhandledSorted(second_part);
2158 void LAllocator::Spill(LiveRange* range) {
2159 ASSERT(!range->IsSpilled());
2160 TraceAlloc("Spilling live range %d\n", range->id());
2161 LiveRange* first = range->TopLevel();
2163 if (!first->HasAllocatedSpillOperand()) {
2164 LOperand* op = TryReuseSpillSlot(range);
2165 if (op == NULL) op = chunk_->GetNextSpillSlot(range->Kind());
2166 first->SetSpillOperand(op);
2168 range->MakeSpilled(chunk()->zone());
2172 int LAllocator::RegisterCount() const {
2173 return num_registers_;
2180 void LAllocator::Verify() const {
2181 for (int i = 0; i < live_ranges()->length(); ++i) {
2182 LiveRange* current = live_ranges()->at(i);
2183 if (current != NULL) current->Verify();
2191 LAllocatorPhase::LAllocatorPhase(const char* name, LAllocator* allocator)
2192 : CompilationPhase(name, allocator->graph()->info()),
2193 allocator_(allocator) {
2194 if (FLAG_hydrogen_stats) {
2195 allocator_zone_start_allocation_size_ =
2196 allocator->zone()->allocation_size();
2201 LAllocatorPhase::~LAllocatorPhase() {
2202 if (FLAG_hydrogen_stats) {
2203 unsigned size = allocator_->zone()->allocation_size() -
2204 allocator_zone_start_allocation_size_;
2205 isolate()->GetHStatistics()->SaveTiming(name(), TimeDelta(), size);
2208 if (ShouldProduceTraceOutput()) {
2209 isolate()->GetHTracer()->TraceLithium(name(), allocator_->chunk());
2210 isolate()->GetHTracer()->TraceLiveRanges(name(), allocator_);
2214 if (allocator_ != NULL) allocator_->Verify();
2219 } } // namespace v8::internal