1 // Copyright 2012 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include "src/crankshaft/lithium.h"
6 
7 #include "src/ast/scopes.h"
8 
9 #if V8_TARGET_ARCH_IA32
10 #include "src/crankshaft/ia32/lithium-ia32.h"  // NOLINT
11 #include "src/crankshaft/ia32/lithium-codegen-ia32.h"  // NOLINT
12 #elif V8_TARGET_ARCH_X64
13 #include "src/crankshaft/x64/lithium-x64.h"  // NOLINT
14 #include "src/crankshaft/x64/lithium-codegen-x64.h"  // NOLINT
15 #elif V8_TARGET_ARCH_ARM
16 #include "src/crankshaft/arm/lithium-arm.h"  // NOLINT
17 #include "src/crankshaft/arm/lithium-codegen-arm.h"  // NOLINT
18 #elif V8_TARGET_ARCH_PPC
19 #include "src/crankshaft/ppc/lithium-ppc.h"          // NOLINT
20 #include "src/crankshaft/ppc/lithium-codegen-ppc.h"  // NOLINT
21 #elif V8_TARGET_ARCH_MIPS
22 #include "src/crankshaft/mips/lithium-mips.h"  // NOLINT
23 #include "src/crankshaft/mips/lithium-codegen-mips.h"  // NOLINT
24 #elif V8_TARGET_ARCH_ARM64
25 #include "src/crankshaft/arm64/lithium-arm64.h"  // NOLINT
26 #include "src/crankshaft/arm64/lithium-codegen-arm64.h"  // NOLINT
27 #elif V8_TARGET_ARCH_MIPS64
28 #include "src/crankshaft/mips64/lithium-mips64.h"  // NOLINT
29 #include "src/crankshaft/mips64/lithium-codegen-mips64.h"  // NOLINT
30 #elif V8_TARGET_ARCH_X87
31 #include "src/crankshaft/x87/lithium-x87.h"  // NOLINT
32 #include "src/crankshaft/x87/lithium-codegen-x87.h"  // NOLINT
33 #else
34 #error "Unknown architecture."
35 #endif
36 
37 namespace v8 {
38 namespace internal {
39 
40 
PrintTo(StringStream * stream)41 void LOperand::PrintTo(StringStream* stream) {
42   LUnallocated* unalloc = NULL;
43   switch (kind()) {
44     case INVALID:
45       stream->Add("(0)");
46       break;
47     case UNALLOCATED:
48       unalloc = LUnallocated::cast(this);
49       stream->Add("v%d", unalloc->virtual_register());
50       if (unalloc->basic_policy() == LUnallocated::FIXED_SLOT) {
51         stream->Add("(=%dS)", unalloc->fixed_slot_index());
52         break;
53       }
54       switch (unalloc->extended_policy()) {
55         case LUnallocated::NONE:
56           break;
57         case LUnallocated::FIXED_REGISTER: {
58           int reg_index = unalloc->fixed_register_index();
59           if (reg_index < 0 || reg_index >= Register::kNumRegisters) {
60             stream->Add("(=invalid_reg#%d)", reg_index);
61           } else {
62             const char* register_name =
63                 Register::from_code(reg_index).ToString();
64             stream->Add("(=%s)", register_name);
65           }
66           break;
67         }
68         case LUnallocated::FIXED_DOUBLE_REGISTER: {
69           int reg_index = unalloc->fixed_register_index();
70           if (reg_index < 0 || reg_index >= DoubleRegister::kMaxNumRegisters) {
71             stream->Add("(=invalid_double_reg#%d)", reg_index);
72           } else {
73             const char* double_register_name =
74                 DoubleRegister::from_code(reg_index).ToString();
75             stream->Add("(=%s)", double_register_name);
76           }
77           break;
78         }
79         case LUnallocated::MUST_HAVE_REGISTER:
80           stream->Add("(R)");
81           break;
82         case LUnallocated::MUST_HAVE_DOUBLE_REGISTER:
83           stream->Add("(D)");
84           break;
85         case LUnallocated::WRITABLE_REGISTER:
86           stream->Add("(WR)");
87           break;
88         case LUnallocated::SAME_AS_FIRST_INPUT:
89           stream->Add("(1)");
90           break;
91         case LUnallocated::ANY:
92           stream->Add("(-)");
93           break;
94       }
95       break;
96     case CONSTANT_OPERAND:
97       stream->Add("[constant:%d]", index());
98       break;
99     case STACK_SLOT:
100       stream->Add("[stack:%d]", index());
101       break;
102     case DOUBLE_STACK_SLOT:
103       stream->Add("[double_stack:%d]", index());
104       break;
105     case REGISTER: {
106       int reg_index = index();
107       if (reg_index < 0 || reg_index >= Register::kNumRegisters) {
108         stream->Add("(=invalid_reg#%d|R)", reg_index);
109       } else {
110         stream->Add("[%s|R]", Register::from_code(reg_index).ToString());
111       }
112       break;
113     }
114     case DOUBLE_REGISTER: {
115       int reg_index = index();
116       if (reg_index < 0 || reg_index >= DoubleRegister::kMaxNumRegisters) {
117         stream->Add("(=invalid_double_reg#%d|R)", reg_index);
118       } else {
119         stream->Add("[%s|R]", DoubleRegister::from_code(reg_index).ToString());
120       }
121       break;
122     }
123   }
124 }
125 
126 
127 template<LOperand::Kind kOperandKind, int kNumCachedOperands>
128 LSubKindOperand<kOperandKind, kNumCachedOperands>*
129 LSubKindOperand<kOperandKind, kNumCachedOperands>::cache = NULL;
130 
131 
132 template<LOperand::Kind kOperandKind, int kNumCachedOperands>
SetUpCache()133 void LSubKindOperand<kOperandKind, kNumCachedOperands>::SetUpCache() {
134   if (cache) return;
135   cache = new LSubKindOperand[kNumCachedOperands];
136   for (int i = 0; i < kNumCachedOperands; i++) {
137     cache[i].ConvertTo(kOperandKind, i);
138   }
139 }
140 
141 
142 template<LOperand::Kind kOperandKind, int kNumCachedOperands>
TearDownCache()143 void LSubKindOperand<kOperandKind, kNumCachedOperands>::TearDownCache() {
144   delete[] cache;
145   cache = NULL;
146 }
147 
148 
SetUpCaches()149 void LOperand::SetUpCaches() {
150 #define LITHIUM_OPERAND_SETUP(name, type, number) L##name::SetUpCache();
151   LITHIUM_OPERAND_LIST(LITHIUM_OPERAND_SETUP)
152 #undef LITHIUM_OPERAND_SETUP
153 }
154 
155 
TearDownCaches()156 void LOperand::TearDownCaches() {
157 #define LITHIUM_OPERAND_TEARDOWN(name, type, number) L##name::TearDownCache();
158   LITHIUM_OPERAND_LIST(LITHIUM_OPERAND_TEARDOWN)
159 #undef LITHIUM_OPERAND_TEARDOWN
160 }
161 
162 
IsRedundant() const163 bool LParallelMove::IsRedundant() const {
164   for (int i = 0; i < move_operands_.length(); ++i) {
165     if (!move_operands_[i].IsRedundant()) return false;
166   }
167   return true;
168 }
169 
170 
PrintDataTo(StringStream * stream) const171 void LParallelMove::PrintDataTo(StringStream* stream) const {
172   bool first = true;
173   for (int i = 0; i < move_operands_.length(); ++i) {
174     if (!move_operands_[i].IsEliminated()) {
175       LOperand* source = move_operands_[i].source();
176       LOperand* destination = move_operands_[i].destination();
177       if (!first) stream->Add(" ");
178       first = false;
179       if (source->Equals(destination)) {
180         destination->PrintTo(stream);
181       } else {
182         destination->PrintTo(stream);
183         stream->Add(" = ");
184         source->PrintTo(stream);
185       }
186       stream->Add(";");
187     }
188   }
189 }
190 
191 
PrintTo(StringStream * stream)192 void LEnvironment::PrintTo(StringStream* stream) {
193   stream->Add("[id=%d|", ast_id().ToInt());
194   if (deoptimization_index() != Safepoint::kNoDeoptimizationIndex) {
195     stream->Add("deopt_id=%d|", deoptimization_index());
196   }
197   stream->Add("parameters=%d|", parameter_count());
198   stream->Add("arguments_stack_height=%d|", arguments_stack_height());
199   for (int i = 0; i < values_.length(); ++i) {
200     if (i != 0) stream->Add(";");
201     if (values_[i] == NULL) {
202       stream->Add("[hole]");
203     } else {
204       values_[i]->PrintTo(stream);
205     }
206   }
207   stream->Add("]");
208 }
209 
210 
RecordPointer(LOperand * op,Zone * zone)211 void LPointerMap::RecordPointer(LOperand* op, Zone* zone) {
212   // Do not record arguments as pointers.
213   if (op->IsStackSlot() && op->index() < 0) return;
214   DCHECK(!op->IsDoubleRegister() && !op->IsDoubleStackSlot());
215   pointer_operands_.Add(op, zone);
216 }
217 
218 
RemovePointer(LOperand * op)219 void LPointerMap::RemovePointer(LOperand* op) {
220   // Do not record arguments as pointers.
221   if (op->IsStackSlot() && op->index() < 0) return;
222   DCHECK(!op->IsDoubleRegister() && !op->IsDoubleStackSlot());
223   for (int i = 0; i < pointer_operands_.length(); ++i) {
224     if (pointer_operands_[i]->Equals(op)) {
225       pointer_operands_.Remove(i);
226       --i;
227     }
228   }
229 }
230 
231 
RecordUntagged(LOperand * op,Zone * zone)232 void LPointerMap::RecordUntagged(LOperand* op, Zone* zone) {
233   // Do not record arguments as pointers.
234   if (op->IsStackSlot() && op->index() < 0) return;
235   DCHECK(!op->IsDoubleRegister() && !op->IsDoubleStackSlot());
236   untagged_operands_.Add(op, zone);
237 }
238 
239 
PrintTo(StringStream * stream)240 void LPointerMap::PrintTo(StringStream* stream) {
241   stream->Add("{");
242   for (int i = 0; i < pointer_operands_.length(); ++i) {
243     if (i != 0) stream->Add(";");
244     pointer_operands_[i]->PrintTo(stream);
245   }
246   stream->Add("}");
247 }
248 
249 
StackSlotOffset(int index)250 int StackSlotOffset(int index) {
251   if (index >= 0) {
252     // Local or spill slot. Skip the frame pointer, function, and
253     // context in the fixed part of the frame.
254     return -(index + 1) * kPointerSize -
255         StandardFrameConstants::kFixedFrameSizeFromFp;
256   } else {
257     // Incoming parameter. Skip the return address.
258     return -(index + 1) * kPointerSize + kFPOnStackSize + kPCOnStackSize;
259   }
260 }
261 
262 
LChunk(CompilationInfo * info,HGraph * graph)263 LChunk::LChunk(CompilationInfo* info, HGraph* graph)
264     : spill_slot_count_(0),
265       info_(info),
266       graph_(graph),
267       instructions_(32, info->zone()),
268       pointer_maps_(8, info->zone()),
269       inlined_functions_(1, info->zone()),
270       deprecation_dependencies_(32, info->zone()),
271       stability_dependencies_(8, info->zone()) {}
272 
273 
GetLabel(int block_id) const274 LLabel* LChunk::GetLabel(int block_id) const {
275   HBasicBlock* block = graph_->blocks()->at(block_id);
276   int first_instruction = block->first_instruction_index();
277   return LLabel::cast(instructions_[first_instruction]);
278 }
279 
280 
LookupDestination(int block_id) const281 int LChunk::LookupDestination(int block_id) const {
282   LLabel* cur = GetLabel(block_id);
283   while (cur->replacement() != NULL) {
284     cur = cur->replacement();
285   }
286   return cur->block_id();
287 }
288 
GetAssemblyLabel(int block_id) const289 Label* LChunk::GetAssemblyLabel(int block_id) const {
290   LLabel* label = GetLabel(block_id);
291   DCHECK(!label->HasReplacement());
292   return label->label();
293 }
294 
295 
MarkEmptyBlocks()296 void LChunk::MarkEmptyBlocks() {
297   LPhase phase("L_Mark empty blocks", this);
298   for (int i = 0; i < graph()->blocks()->length(); ++i) {
299     HBasicBlock* block = graph()->blocks()->at(i);
300     int first = block->first_instruction_index();
301     int last = block->last_instruction_index();
302     LInstruction* first_instr = instructions()->at(first);
303     LInstruction* last_instr = instructions()->at(last);
304 
305     LLabel* label = LLabel::cast(first_instr);
306     if (last_instr->IsGoto()) {
307       LGoto* goto_instr = LGoto::cast(last_instr);
308       if (label->IsRedundant() &&
309           !label->is_loop_header()) {
310         bool can_eliminate = true;
311         for (int i = first + 1; i < last && can_eliminate; ++i) {
312           LInstruction* cur = instructions()->at(i);
313           if (cur->IsGap()) {
314             LGap* gap = LGap::cast(cur);
315             if (!gap->IsRedundant()) {
316               can_eliminate = false;
317             }
318           } else {
319             can_eliminate = false;
320           }
321         }
322         if (can_eliminate) {
323           label->set_replacement(GetLabel(goto_instr->block_id()));
324         }
325       }
326     }
327   }
328 }
329 
330 
AddInstruction(LInstruction * instr,HBasicBlock * block)331 void LChunk::AddInstruction(LInstruction* instr, HBasicBlock* block) {
332   LInstructionGap* gap = new (zone()) LInstructionGap(block);
333   gap->set_hydrogen_value(instr->hydrogen_value());
334   int index = -1;
335   if (instr->IsControl()) {
336     instructions_.Add(gap, zone());
337     index = instructions_.length();
338     instructions_.Add(instr, zone());
339   } else {
340     index = instructions_.length();
341     instructions_.Add(instr, zone());
342     instructions_.Add(gap, zone());
343   }
344   if (instr->HasPointerMap()) {
345     pointer_maps_.Add(instr->pointer_map(), zone());
346     instr->pointer_map()->set_lithium_position(index);
347   }
348 }
349 
350 
DefineConstantOperand(HConstant * constant)351 LConstantOperand* LChunk::DefineConstantOperand(HConstant* constant) {
352   return LConstantOperand::Create(constant->id(), zone());
353 }
354 
355 
GetParameterStackSlot(int index) const356 int LChunk::GetParameterStackSlot(int index) const {
357   // The receiver is at index 0, the first parameter at index 1, so we
358   // shift all parameter indexes down by the number of parameters, and
359   // make sure they end up negative so they are distinguishable from
360   // spill slots.
361   int result = index - info()->num_parameters() - 1;
362 
363   DCHECK(result < 0);
364   return result;
365 }
366 
367 
368 // A parameter relative to ebp in the arguments stub.
ParameterAt(int index)369 int LChunk::ParameterAt(int index) {
370   DCHECK(-1 <= index);  // -1 is the receiver.
371   return (1 + info()->scope()->num_parameters() - index) *
372       kPointerSize;
373 }
374 
375 
GetGapAt(int index) const376 LGap* LChunk::GetGapAt(int index) const {
377   return LGap::cast(instructions_[index]);
378 }
379 
380 
IsGapAt(int index) const381 bool LChunk::IsGapAt(int index) const {
382   return instructions_[index]->IsGap();
383 }
384 
385 
NearestGapPos(int index) const386 int LChunk::NearestGapPos(int index) const {
387   while (!IsGapAt(index)) index--;
388   return index;
389 }
390 
391 
AddGapMove(int index,LOperand * from,LOperand * to)392 void LChunk::AddGapMove(int index, LOperand* from, LOperand* to) {
393   GetGapAt(index)->GetOrCreateParallelMove(
394       LGap::START, zone())->AddMove(from, to, zone());
395 }
396 
397 
LookupConstant(LConstantOperand * operand) const398 HConstant* LChunk::LookupConstant(LConstantOperand* operand) const {
399   return HConstant::cast(graph_->LookupValue(operand->index()));
400 }
401 
402 
LookupLiteralRepresentation(LConstantOperand * operand) const403 Representation LChunk::LookupLiteralRepresentation(
404     LConstantOperand* operand) const {
405   return graph_->LookupValue(operand->index())->representation();
406 }
407 
408 
CommitDependencies(Handle<Code> code) const409 void LChunk::CommitDependencies(Handle<Code> code) const {
410   if (!code->is_optimized_code()) return;
411   HandleScope scope(isolate());
412 
413   for (Handle<Map> map : deprecation_dependencies_) {
414     DCHECK(!map->is_deprecated());
415     DCHECK(map->CanBeDeprecated());
416     Map::AddDependentCode(map, DependentCode::kTransitionGroup, code);
417   }
418 
419   for (Handle<Map> map : stability_dependencies_) {
420     DCHECK(map->is_stable());
421     DCHECK(map->CanTransition());
422     Map::AddDependentCode(map, DependentCode::kPrototypeCheckGroup, code);
423   }
424 
425   info_->dependencies()->Commit(code);
426 }
427 
428 
NewChunk(HGraph * graph)429 LChunk* LChunk::NewChunk(HGraph* graph) {
430   DisallowHandleAllocation no_handles;
431   DisallowHeapAllocation no_gc;
432   graph->DisallowAddingNewValues();
433   int values = graph->GetMaximumValueID();
434   CompilationInfo* info = graph->info();
435   if (values > LUnallocated::kMaxVirtualRegisters) {
436     info->AbortOptimization(kNotEnoughVirtualRegistersForValues);
437     return NULL;
438   }
439   LAllocator allocator(values, graph);
440   LChunkBuilder builder(info, graph, &allocator);
441   LChunk* chunk = builder.Build();
442   if (chunk == NULL) return NULL;
443 
444   if (!allocator.Allocate(chunk)) {
445     info->AbortOptimization(kNotEnoughVirtualRegistersRegalloc);
446     return NULL;
447   }
448 
449   chunk->set_allocated_double_registers(
450       allocator.assigned_double_registers());
451 
452   return chunk;
453 }
454 
455 
Codegen()456 Handle<Code> LChunk::Codegen() {
457   MacroAssembler assembler(info()->isolate(), NULL, 0,
458                            CodeObjectRequired::kYes);
459   LOG_CODE_EVENT(info()->isolate(),
460                  CodeStartLinePosInfoRecordEvent(
461                      assembler.positions_recorder()));
462   // Code serializer only takes unoptimized code.
463   DCHECK(!info()->will_serialize());
464   LCodeGen generator(this, &assembler, info());
465 
466   MarkEmptyBlocks();
467 
468   if (generator.GenerateCode()) {
469     generator.CheckEnvironmentUsage();
470     CodeGenerator::MakeCodePrologue(info(), "optimized");
471     Handle<Code> code = CodeGenerator::MakeCodeEpilogue(&assembler, info());
472     generator.FinishCode(code);
473     CommitDependencies(code);
474     code->set_is_crankshafted(true);
475     void* jit_handler_data =
476         assembler.positions_recorder()->DetachJITHandlerData();
477     LOG_CODE_EVENT(info()->isolate(),
478                    CodeEndLinePosInfoRecordEvent(*code, jit_handler_data));
479 
480     CodeGenerator::PrintCode(code, info());
481     DCHECK(!(info()->isolate()->serializer_enabled() &&
482              info()->GetMustNotHaveEagerFrame() &&
483              generator.NeedsEagerFrame()));
484     return code;
485   }
486   assembler.AbortedCodeGeneration();
487   return Handle<Code>::null();
488 }
489 
490 
set_allocated_double_registers(BitVector * allocated_registers)491 void LChunk::set_allocated_double_registers(BitVector* allocated_registers) {
492   allocated_double_registers_ = allocated_registers;
493   BitVector* doubles = allocated_double_registers();
494   BitVector::Iterator iterator(doubles);
495   while (!iterator.Done()) {
496     if (info()->saves_caller_doubles()) {
497       if (kDoubleSize == kPointerSize * 2) {
498         spill_slot_count_ += 2;
499       } else {
500         spill_slot_count_++;
501       }
502     }
503     iterator.Advance();
504   }
505 }
506 
507 
Abort(BailoutReason reason)508 void LChunkBuilderBase::Abort(BailoutReason reason) {
509   info()->AbortOptimization(reason);
510   status_ = ABORTED;
511 }
512 
513 
Retry(BailoutReason reason)514 void LChunkBuilderBase::Retry(BailoutReason reason) {
515   info()->RetryOptimization(reason);
516   status_ = ABORTED;
517 }
518 
519 
CreateEnvironment(HEnvironment * hydrogen_env,int * argument_index_accumulator,ZoneList<HValue * > * objects_to_materialize)520 LEnvironment* LChunkBuilderBase::CreateEnvironment(
521     HEnvironment* hydrogen_env, int* argument_index_accumulator,
522     ZoneList<HValue*>* objects_to_materialize) {
523   if (hydrogen_env == NULL) return NULL;
524 
525   LEnvironment* outer =
526       CreateEnvironment(hydrogen_env->outer(), argument_index_accumulator,
527                         objects_to_materialize);
528   BailoutId ast_id = hydrogen_env->ast_id();
529   DCHECK(!ast_id.IsNone() ||
530          hydrogen_env->frame_type() != JS_FUNCTION);
531 
532   int omitted_count = (hydrogen_env->frame_type() == JS_FUNCTION)
533                           ? 0
534                           : hydrogen_env->specials_count();
535 
536   int value_count = hydrogen_env->length() - omitted_count;
537   LEnvironment* result =
538       new(zone()) LEnvironment(hydrogen_env->closure(),
539                                hydrogen_env->frame_type(),
540                                ast_id,
541                                hydrogen_env->parameter_count(),
542                                argument_count_,
543                                value_count,
544                                outer,
545                                hydrogen_env->entry(),
546                                zone());
547   int argument_index = *argument_index_accumulator;
548 
549   // Store the environment description into the environment
550   // (with holes for nested objects)
551   for (int i = 0; i < hydrogen_env->length(); ++i) {
552     if (hydrogen_env->is_special_index(i) &&
553         hydrogen_env->frame_type() != JS_FUNCTION) {
554       continue;
555     }
556     LOperand* op;
557     HValue* value = hydrogen_env->values()->at(i);
558     CHECK(!value->IsPushArguments());  // Do not deopt outgoing arguments
559     if (value->IsArgumentsObject() || value->IsCapturedObject()) {
560       op = LEnvironment::materialization_marker();
561     } else {
562       op = UseAny(value);
563     }
564     result->AddValue(op,
565                      value->representation(),
566                      value->CheckFlag(HInstruction::kUint32));
567   }
568 
569   // Recursively store the nested objects into the environment
570   for (int i = 0; i < hydrogen_env->length(); ++i) {
571     if (hydrogen_env->is_special_index(i)) continue;
572 
573     HValue* value = hydrogen_env->values()->at(i);
574     if (value->IsArgumentsObject() || value->IsCapturedObject()) {
575       AddObjectToMaterialize(value, objects_to_materialize, result);
576     }
577   }
578 
579   if (hydrogen_env->frame_type() == JS_FUNCTION) {
580     *argument_index_accumulator = argument_index;
581   }
582 
583   return result;
584 }
585 
586 
587 // Add an object to the supplied environment and object materialization list.
588 //
589 // Notes:
590 //
591 // We are building three lists here:
592 //
593 // 1. In the result->object_mapping_ list (added to by the
594 //    LEnvironment::Add*Object methods), we store the lengths (number
595 //    of fields) of the captured objects in depth-first traversal order, or
596 //    in case of duplicated objects, we store the index to the duplicate object
597 //    (with a tag to differentiate between captured and duplicated objects).
598 //
599 // 2. The object fields are stored in the result->values_ list
600 //    (added to by the LEnvironment.AddValue method) sequentially as lists
601 //    of fields with holes for nested objects (the holes will be expanded
602 //    later by LCodegen::AddToTranslation according to the
603 //    LEnvironment.object_mapping_ list).
604 //
605 // 3. The auxiliary objects_to_materialize array stores the hydrogen values
606 //    in the same order as result->object_mapping_ list. This is used
607 //    to detect duplicate values and calculate the corresponding object index.
AddObjectToMaterialize(HValue * value,ZoneList<HValue * > * objects_to_materialize,LEnvironment * result)608 void LChunkBuilderBase::AddObjectToMaterialize(HValue* value,
609     ZoneList<HValue*>* objects_to_materialize, LEnvironment* result) {
610   int object_index = objects_to_materialize->length();
611   // Store the hydrogen value into the de-duplication array
612   objects_to_materialize->Add(value, zone());
613   // Find out whether we are storing a duplicated value
614   int previously_materialized_object = -1;
615   for (int prev = 0; prev < object_index; ++prev) {
616     if (objects_to_materialize->at(prev) == value) {
617       previously_materialized_object = prev;
618       break;
619     }
620   }
621   // Store the captured object length (or duplicated object index)
622   // into the environment. For duplicated objects, we stop here.
623   int length = value->OperandCount();
624   bool is_arguments = value->IsArgumentsObject();
625   if (previously_materialized_object >= 0) {
626     result->AddDuplicateObject(previously_materialized_object);
627     return;
628   } else {
629     result->AddNewObject(is_arguments ? length - 1 : length, is_arguments);
630   }
631   // Store the captured object's fields into the environment
632   for (int i = is_arguments ? 1 : 0; i < length; ++i) {
633     LOperand* op;
634     HValue* arg_value = value->OperandAt(i);
635     if (arg_value->IsArgumentsObject() || arg_value->IsCapturedObject()) {
636       // Insert a hole for nested objects
637       op = LEnvironment::materialization_marker();
638     } else {
639       DCHECK(!arg_value->IsPushArguments());
640       // For ordinary values, tell the register allocator we need the value
641       // to be alive here
642       op = UseAny(arg_value);
643     }
644     result->AddValue(op,
645                      arg_value->representation(),
646                      arg_value->CheckFlag(HInstruction::kUint32));
647   }
648   // Recursively store all the nested captured objects into the environment
649   for (int i = is_arguments ? 1 : 0; i < length; ++i) {
650     HValue* arg_value = value->OperandAt(i);
651     if (arg_value->IsArgumentsObject() || arg_value->IsCapturedObject()) {
652       AddObjectToMaterialize(arg_value, objects_to_materialize, result);
653     }
654   }
655 }
656 
657 
~LPhase()658 LPhase::~LPhase() {
659   if (ShouldProduceTraceOutput()) {
660     isolate()->GetHTracer()->TraceLithium(name(), chunk_);
661   }
662 }
663 
664 
665 }  // namespace internal
666 }  // namespace v8
667