deps/v8/src/lithium.cc

   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/lithium.h"
   6
   7 #include "src/v8.h"
   8
   9 #include "src/scopes.h"
  10 #include "src/serialize.h"
  11
  12 #if V8_TARGET_ARCH_IA32
  13 #include "src/ia32/lithium-ia32.h"  // NOLINT
  14 #include "src/ia32/lithium-codegen-ia32.h"  // NOLINT
  15 #elif V8_TARGET_ARCH_X64
  16 #include "src/x64/lithium-x64.h"  // NOLINT
  17 #include "src/x64/lithium-codegen-x64.h"  // NOLINT
  18 #elif V8_TARGET_ARCH_ARM
  19 #include "src/arm/lithium-arm.h"  // NOLINT
  20 #include "src/arm/lithium-codegen-arm.h"  // NOLINT
  21 #elif V8_TARGET_ARCH_PPC
  22 #include "src/ppc/lithium-ppc.h"          // NOLINT
  23 #include "src/ppc/lithium-codegen-ppc.h"  // NOLINT
  24 #elif V8_TARGET_ARCH_MIPS
  25 #include "src/mips/lithium-mips.h"  // NOLINT
  26 #include "src/mips/lithium-codegen-mips.h"  // NOLINT
  27 #elif V8_TARGET_ARCH_ARM64
  28 #include "src/arm64/lithium-arm64.h"  // NOLINT
  29 #include "src/arm64/lithium-codegen-arm64.h"  // NOLINT
  30 #elif V8_TARGET_ARCH_MIPS64
  31 #include "src/mips64/lithium-mips64.h"  // NOLINT
  32 #include "src/mips64/lithium-codegen-mips64.h"  // NOLINT
  33 #elif V8_TARGET_ARCH_X87
  34 #include "src/x87/lithium-x87.h"  // NOLINT
  35 #include "src/x87/lithium-codegen-x87.h"  // NOLINT
  36 #else
  37 #error "Unknown architecture."
  38 #endif
  39
  40 namespace v8 {
  41 namespace internal {
  42
  43
  44 void LOperand::PrintTo(StringStream* stream) {
  45   LUnallocated* unalloc = NULL;
  46   switch (kind()) {
  47     case INVALID:
  48       stream->Add("(0)");
  49       break;
  50     case UNALLOCATED:
  51       unalloc = LUnallocated::cast(this);
  52       stream->Add("v%d", unalloc->virtual_register());
  53       if (unalloc->basic_policy() == LUnallocated::FIXED_SLOT) {
  54         stream->Add("(=%dS)", unalloc->fixed_slot_index());
  55         break;
  56       }
  57       switch (unalloc->extended_policy()) {
  58         case LUnallocated::NONE:
  59           break;
  60         case LUnallocated::FIXED_REGISTER: {
  61           int reg_index = unalloc->fixed_register_index();
  62           if (reg_index < 0 ||
  63               reg_index >= Register::kMaxNumAllocatableRegisters) {
  64             stream->Add("(=invalid_reg#%d)", reg_index);
  65           } else {
  66             const char* register_name =
  67                 Register::AllocationIndexToString(reg_index);
  68             stream->Add("(=%s)", register_name);
  69           }
  70           break;
  71         }
  72         case LUnallocated::FIXED_DOUBLE_REGISTER: {
  73           int reg_index = unalloc->fixed_register_index();
  74           if (reg_index < 0 ||
  75               reg_index >= DoubleRegister::kMaxNumAllocatableRegisters) {
  76             stream->Add("(=invalid_double_reg#%d)", reg_index);
  77           } else {
  78             const char* double_register_name =
  79                 DoubleRegister::AllocationIndexToString(reg_index);
  80             stream->Add("(=%s)", double_register_name);
  81           }
  82           break;
  83         }
  84         case LUnallocated::MUST_HAVE_REGISTER:
  85           stream->Add("(R)");
  86           break;
  87         case LUnallocated::MUST_HAVE_DOUBLE_REGISTER:
  88           stream->Add("(D)");
  89           break;
  90         case LUnallocated::WRITABLE_REGISTER:
  91           stream->Add("(WR)");
  92           break;
  93         case LUnallocated::SAME_AS_FIRST_INPUT:
  94           stream->Add("(1)");
  95           break;
  96         case LUnallocated::ANY:
  97           stream->Add("(-)");
  98           break;
  99       }
 100       break;
 101     case CONSTANT_OPERAND:
 102       stream->Add("[constant:%d]", index());
 103       break;
 104     case STACK_SLOT:
 105       stream->Add("[stack:%d]", index());
 106       break;
 107     case DOUBLE_STACK_SLOT:
 108       stream->Add("[double_stack:%d]", index());
 109       break;
 110     case REGISTER: {
 111       int reg_index = index();
 112       if (reg_index < 0 || reg_index >= Register::kMaxNumAllocatableRegisters) {
 113         stream->Add("(=invalid_reg#%d|R)", reg_index);
 114       } else {
 115         stream->Add("[%s|R]", Register::AllocationIndexToString(reg_index));
 116       }
 117       break;
 118     }
 119     case DOUBLE_REGISTER: {
 120       int reg_index = index();
 121       if (reg_index < 0 ||
 122           reg_index >= DoubleRegister::kMaxNumAllocatableRegisters) {
 123         stream->Add("(=invalid_double_reg#%d|R)", reg_index);
 124       } else {
 125         stream->Add("[%s|R]",
 126                     DoubleRegister::AllocationIndexToString(reg_index));
 127       }
 128       break;
 129     }
 130   }
 131 }
 132
 133
 134 template<LOperand::Kind kOperandKind, int kNumCachedOperands>
 135 LSubKindOperand<kOperandKind, kNumCachedOperands>*
 136 LSubKindOperand<kOperandKind, kNumCachedOperands>::cache = NULL;
 137
 138
 139 template<LOperand::Kind kOperandKind, int kNumCachedOperands>
 140 void LSubKindOperand<kOperandKind, kNumCachedOperands>::SetUpCache() {
 141   if (cache) return;
 142   cache = new LSubKindOperand[kNumCachedOperands];
 143   for (int i = 0; i < kNumCachedOperands; i++) {
 144     cache[i].ConvertTo(kOperandKind, i);
 145   }
 146 }
 147
 148
 149 template<LOperand::Kind kOperandKind, int kNumCachedOperands>
 150 void LSubKindOperand<kOperandKind, kNumCachedOperands>::TearDownCache() {
 151   delete[] cache;
 152   cache = NULL;
 153 }
 154
 155
 156 void LOperand::SetUpCaches() {
 157 #define LITHIUM_OPERAND_SETUP(name, type, number) L##name::SetUpCache();
 158   LITHIUM_OPERAND_LIST(LITHIUM_OPERAND_SETUP)
 159 #undef LITHIUM_OPERAND_SETUP
 160 }
 161
 162
 163 void LOperand::TearDownCaches() {
 164 #define LITHIUM_OPERAND_TEARDOWN(name, type, number) L##name::TearDownCache();
 165   LITHIUM_OPERAND_LIST(LITHIUM_OPERAND_TEARDOWN)
 166 #undef LITHIUM_OPERAND_TEARDOWN
 167 }
 168
 169
 170 bool LParallelMove::IsRedundant() const {
 171   for (int i = 0; i < move_operands_.length(); ++i) {
 172     if (!move_operands_[i].IsRedundant()) return false;
 173   }
 174   return true;
 175 }
 176
 177
 178 void LParallelMove::PrintDataTo(StringStream* stream) const {
 179   bool first = true;
 180   for (int i = 0; i < move_operands_.length(); ++i) {
 181     if (!move_operands_[i].IsEliminated()) {
 182       LOperand* source = move_operands_[i].source();
 183       LOperand* destination = move_operands_[i].destination();
 184       if (!first) stream->Add(" ");
 185       first = false;
 186       if (source->Equals(destination)) {
 187         destination->PrintTo(stream);
 188       } else {
 189         destination->PrintTo(stream);
 190         stream->Add(" = ");
 191         source->PrintTo(stream);
 192       }
 193       stream->Add(";");
 194     }
 195   }
 196 }
 197
 198
 199 void LEnvironment::PrintTo(StringStream* stream) {
 200   stream->Add("[id=%d|", ast_id().ToInt());
 201   if (deoptimization_index() != Safepoint::kNoDeoptimizationIndex) {
 202     stream->Add("deopt_id=%d|", deoptimization_index());
 203   }
 204   stream->Add("parameters=%d|", parameter_count());
 205   stream->Add("arguments_stack_height=%d|", arguments_stack_height());
 206   for (int i = 0; i < values_.length(); ++i) {
 207     if (i != 0) stream->Add(";");
 208     if (values_[i] == NULL) {
 209       stream->Add("[hole]");
 210     } else {
 211       values_[i]->PrintTo(stream);
 212     }
 213   }
 214   stream->Add("]");
 215 }
 216
 217
 218 void LPointerMap::RecordPointer(LOperand* op, Zone* zone) {
 219   // Do not record arguments as pointers.
 220   if (op->IsStackSlot() && op->index() < 0) return;
 221   DCHECK(!op->IsDoubleRegister() && !op->IsDoubleStackSlot());
 222   pointer_operands_.Add(op, zone);
 223 }
 224
 225
 226 void LPointerMap::RemovePointer(LOperand* op) {
 227   // Do not record arguments as pointers.
 228   if (op->IsStackSlot() && op->index() < 0) return;
 229   DCHECK(!op->IsDoubleRegister() && !op->IsDoubleStackSlot());
 230   for (int i = 0; i < pointer_operands_.length(); ++i) {
 231     if (pointer_operands_[i]->Equals(op)) {
 232       pointer_operands_.Remove(i);
 233       --i;
 234     }
 235   }
 236 }
 237
 238
 239 void LPointerMap::RecordUntagged(LOperand* op, Zone* zone) {
 240   // Do not record arguments as pointers.
 241   if (op->IsStackSlot() && op->index() < 0) return;
 242   DCHECK(!op->IsDoubleRegister() && !op->IsDoubleStackSlot());
 243   untagged_operands_.Add(op, zone);
 244 }
 245
 246
 247 void LPointerMap::PrintTo(StringStream* stream) {
 248   stream->Add("{");
 249   for (int i = 0; i < pointer_operands_.length(); ++i) {
 250     if (i != 0) stream->Add(";");
 251     pointer_operands_[i]->PrintTo(stream);
 252   }
 253   stream->Add("}");
 254 }
 255
 256
 257 int StackSlotOffset(int index) {
 258   if (index >= 0) {
 259     // Local or spill slot. Skip the frame pointer, function, and
 260     // context in the fixed part of the frame.
 261     return -(index + 1) * kPointerSize -
 262         StandardFrameConstants::kFixedFrameSizeFromFp;
 263   } else {
 264     // Incoming parameter. Skip the return address.
 265     return -(index + 1) * kPointerSize + kFPOnStackSize + kPCOnStackSize;
 266   }
 267 }
 268
 269
 270 LChunk::LChunk(CompilationInfo* info, HGraph* graph)
 271     : spill_slot_count_(0),
 272       info_(info),
 273       graph_(graph),
 274       instructions_(32, info->zone()),
 275       pointer_maps_(8, info->zone()),
 276       inlined_closures_(1, info->zone()),
 277       deprecation_dependencies_(MapLess(), MapAllocator(info->zone())),
 278       stability_dependencies_(MapLess(), MapAllocator(info->zone())) {}
 279
 280
 281 LLabel* LChunk::GetLabel(int block_id) const {
 282   HBasicBlock* block = graph_->blocks()->at(block_id);
 283   int first_instruction = block->first_instruction_index();
 284   return LLabel::cast(instructions_[first_instruction]);
 285 }
 286
 287
 288 int LChunk::LookupDestination(int block_id) const {
 289   LLabel* cur = GetLabel(block_id);
 290   while (cur->replacement() != NULL) {
 291     cur = cur->replacement();
 292   }
 293   return cur->block_id();
 294 }
 295
 296 Label* LChunk::GetAssemblyLabel(int block_id) const {
 297   LLabel* label = GetLabel(block_id);
 298   DCHECK(!label->HasReplacement());
 299   return label->label();
 300 }
 301
 302
 303 void LChunk::MarkEmptyBlocks() {
 304   LPhase phase("L_Mark empty blocks", this);
 305   for (int i = 0; i < graph()->blocks()->length(); ++i) {
 306     HBasicBlock* block = graph()->blocks()->at(i);
 307     int first = block->first_instruction_index();
 308     int last = block->last_instruction_index();
 309     LInstruction* first_instr = instructions()->at(first);
 310     LInstruction* last_instr = instructions()->at(last);
 311
 312     LLabel* label = LLabel::cast(first_instr);
 313     if (last_instr->IsGoto()) {
 314       LGoto* goto_instr = LGoto::cast(last_instr);
 315       if (label->IsRedundant() &&
 316           !label->is_loop_header()) {
 317         bool can_eliminate = true;
 318         for (int i = first + 1; i < last && can_eliminate; ++i) {
 319           LInstruction* cur = instructions()->at(i);
 320           if (cur->IsGap()) {
 321             LGap* gap = LGap::cast(cur);
 322             if (!gap->IsRedundant()) {
 323               can_eliminate = false;
 324             }
 325           } else {
 326             can_eliminate = false;
 327           }
 328         }
 329         if (can_eliminate) {
 330           label->set_replacement(GetLabel(goto_instr->block_id()));
 331         }
 332       }
 333     }
 334   }
 335 }
 336
 337
 338 void LChunk::AddInstruction(LInstruction* instr, HBasicBlock* block) {
 339   LInstructionGap* gap = new (zone()) LInstructionGap(block);
 340   gap->set_hydrogen_value(instr->hydrogen_value());
 341   int index = -1;
 342   if (instr->IsControl()) {
 343     instructions_.Add(gap, zone());
 344     index = instructions_.length();
 345     instructions_.Add(instr, zone());
 346   } else {
 347     index = instructions_.length();
 348     instructions_.Add(instr, zone());
 349     instructions_.Add(gap, zone());
 350   }
 351   if (instr->HasPointerMap()) {
 352     pointer_maps_.Add(instr->pointer_map(), zone());
 353     instr->pointer_map()->set_lithium_position(index);
 354   }
 355 }
 356
 357
 358 LConstantOperand* LChunk::DefineConstantOperand(HConstant* constant) {
 359   return LConstantOperand::Create(constant->id(), zone());
 360 }
 361
 362
 363 int LChunk::GetParameterStackSlot(int index) const {
 364   // The receiver is at index 0, the first parameter at index 1, so we
 365   // shift all parameter indexes down by the number of parameters, and
 366   // make sure they end up negative so they are distinguishable from
 367   // spill slots.
 368   int result = index - info()->num_parameters() - 1;
 369
 370   DCHECK(result < 0);
 371   return result;
 372 }
 373
 374
 375 // A parameter relative to ebp in the arguments stub.
 376 int LChunk::ParameterAt(int index) {
 377   DCHECK(-1 <= index);  // -1 is the receiver.
 378   return (1 + info()->scope()->num_parameters() - index) *
 379       kPointerSize;
 380 }
 381
 382
 383 LGap* LChunk::GetGapAt(int index) const {
 384   return LGap::cast(instructions_[index]);
 385 }
 386
 387
 388 bool LChunk::IsGapAt(int index) const {
 389   return instructions_[index]->IsGap();
 390 }
 391
 392
 393 int LChunk::NearestGapPos(int index) const {
 394   while (!IsGapAt(index)) index--;
 395   return index;
 396 }
 397
 398
 399 void LChunk::AddGapMove(int index, LOperand* from, LOperand* to) {
 400   GetGapAt(index)->GetOrCreateParallelMove(
 401       LGap::START, zone())->AddMove(from, to, zone());
 402 }
 403
 404
 405 HConstant* LChunk::LookupConstant(LConstantOperand* operand) const {
 406   return HConstant::cast(graph_->LookupValue(operand->index()));
 407 }
 408
 409
 410 Representation LChunk::LookupLiteralRepresentation(
 411     LConstantOperand* operand) const {
 412   return graph_->LookupValue(operand->index())->representation();
 413 }
 414
 415
 416 static void AddWeakObjectToCodeDependency(Isolate* isolate,
 417                                           Handle<HeapObject> object,
 418                                           Handle<Code> code) {
 419   Handle<WeakCell> cell = Code::WeakCellFor(code);
 420   Heap* heap = isolate->heap();
 421   Handle<DependentCode> dep(heap->LookupWeakObjectToCodeDependency(object));
 422   dep = DependentCode::InsertWeakCode(dep, DependentCode::kWeakCodeGroup, cell);
 423   heap->AddWeakObjectToCodeDependency(object, dep);
 424 }
 425
 426
 427 void LChunk::RegisterWeakObjectsInOptimizedCode(Handle<Code> code) const {
 428   DCHECK(code->is_optimized_code());
 429   ZoneList<Handle<Map> > maps(1, zone());
 430   ZoneList<Handle<HeapObject> > objects(1, zone());
 431   int mode_mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT) |
 432                   RelocInfo::ModeMask(RelocInfo::CELL);
 433   for (RelocIterator it(*code, mode_mask); !it.done(); it.next()) {
 434     RelocInfo::Mode mode = it.rinfo()->rmode();
 435     if (mode == RelocInfo::CELL &&
 436         code->IsWeakObjectInOptimizedCode(it.rinfo()->target_cell())) {
 437       objects.Add(Handle<HeapObject>(it.rinfo()->target_cell()), zone());
 438     } else if (mode == RelocInfo::EMBEDDED_OBJECT &&
 439                code->IsWeakObjectInOptimizedCode(it.rinfo()->target_object())) {
 440       if (it.rinfo()->target_object()->IsMap()) {
 441         Handle<Map> map(Map::cast(it.rinfo()->target_object()));
 442         maps.Add(map, zone());
 443       } else {
 444         Handle<HeapObject> object(
 445             HeapObject::cast(it.rinfo()->target_object()));
 446         objects.Add(object, zone());
 447       }
 448     }
 449   }
 450   for (int i = 0; i < maps.length(); i++) {
 451     Map::AddDependentCode(maps.at(i), DependentCode::kWeakCodeGroup, code);
 452   }
 453   for (int i = 0; i < objects.length(); i++) {
 454     AddWeakObjectToCodeDependency(isolate(), objects.at(i), code);
 455   }
 456   if (FLAG_enable_ool_constant_pool) {
 457     code->constant_pool()->set_weak_object_state(
 458         ConstantPoolArray::WEAK_OBJECTS_IN_OPTIMIZED_CODE);
 459   }
 460   code->set_can_have_weak_objects(true);
 461 }
 462
 463
 464 void LChunk::CommitDependencies(Handle<Code> code) const {
 465   if (!code->is_optimized_code()) return;
 466   HandleScope scope(isolate());
 467
 468   for (MapSet::const_iterator it = deprecation_dependencies_.begin(),
 469        iend = deprecation_dependencies_.end(); it != iend; ++it) {
 470     Handle<Map> map = *it;
 471     DCHECK(!map->is_deprecated());
 472     DCHECK(map->CanBeDeprecated());
 473     Map::AddDependentCode(map, DependentCode::kTransitionGroup, code);
 474   }
 475
 476   for (MapSet::const_iterator it = stability_dependencies_.begin(),
 477        iend = stability_dependencies_.end(); it != iend; ++it) {
 478     Handle<Map> map = *it;
 479     DCHECK(map->is_stable());
 480     DCHECK(map->CanTransition());
 481     Map::AddDependentCode(map, DependentCode::kPrototypeCheckGroup, code);
 482   }
 483
 484   info_->CommitDependencies(code);
 485   RegisterWeakObjectsInOptimizedCode(code);
 486 }
 487
 488
 489 LChunk* LChunk::NewChunk(HGraph* graph) {
 490   DisallowHandleAllocation no_handles;
 491   DisallowHeapAllocation no_gc;
 492   graph->DisallowAddingNewValues();
 493   int values = graph->GetMaximumValueID();
 494   CompilationInfo* info = graph->info();
 495   if (values > LUnallocated::kMaxVirtualRegisters) {
 496     info->AbortOptimization(kNotEnoughVirtualRegistersForValues);
 497     return NULL;
 498   }
 499   LAllocator allocator(values, graph);
 500   LChunkBuilder builder(info, graph, &allocator);
 501   LChunk* chunk = builder.Build();
 502   if (chunk == NULL) return NULL;
 503
 504   if (!allocator.Allocate(chunk)) {
 505     info->AbortOptimization(kNotEnoughVirtualRegistersRegalloc);
 506     return NULL;
 507   }
 508
 509   chunk->set_allocated_double_registers(
 510       allocator.assigned_double_registers());
 511
 512   return chunk;
 513 }
 514
 515
 516 Handle<Code> LChunk::Codegen() {
 517   MacroAssembler assembler(info()->isolate(), NULL, 0);
 518   LOG_CODE_EVENT(info()->isolate(),
 519                  CodeStartLinePosInfoRecordEvent(
 520                      assembler.positions_recorder()));
 521   // Code serializer only takes unoptimized code.
 522   DCHECK(!info()->will_serialize());
 523   LCodeGen generator(this, &assembler, info());
 524
 525   MarkEmptyBlocks();
 526
 527   if (generator.GenerateCode()) {
 528     generator.CheckEnvironmentUsage();
 529     CodeGenerator::MakeCodePrologue(info(), "optimized");
 530     Code::Flags flags = info()->flags();
 531     Handle<Code> code =
 532         CodeGenerator::MakeCodeEpilogue(&assembler, flags, info());
 533     generator.FinishCode(code);
 534     CommitDependencies(code);
 535     code->set_is_crankshafted(true);
 536     void* jit_handler_data =
 537         assembler.positions_recorder()->DetachJITHandlerData();
 538     LOG_CODE_EVENT(info()->isolate(),
 539                    CodeEndLinePosInfoRecordEvent(*code, jit_handler_data));
 540
 541     CodeGenerator::PrintCode(code, info());
 542     DCHECK(!(info()->isolate()->serializer_enabled() &&
 543              info()->GetMustNotHaveEagerFrame() &&
 544              generator.NeedsEagerFrame()));
 545     return code;
 546   }
 547   assembler.AbortedCodeGeneration();
 548   return Handle<Code>::null();
 549 }
 550
 551
 552 void LChunk::set_allocated_double_registers(BitVector* allocated_registers) {
 553   allocated_double_registers_ = allocated_registers;
 554   BitVector* doubles = allocated_double_registers();
 555   BitVector::Iterator iterator(doubles);
 556   while (!iterator.Done()) {
 557     if (info()->saves_caller_doubles()) {
 558       if (kDoubleSize == kPointerSize * 2) {
 559         spill_slot_count_ += 2;
 560       } else {
 561         spill_slot_count_++;
 562       }
 563     }
 564     iterator.Advance();
 565   }
 566 }
 567
 568
 569 void LChunkBuilderBase::Abort(BailoutReason reason) {
 570   info()->AbortOptimization(reason);
 571   status_ = ABORTED;
 572 }
 573
 574
 575 void LChunkBuilderBase::Retry(BailoutReason reason) {
 576   info()->RetryOptimization(reason);
 577   status_ = ABORTED;
 578 }
 579
 580
 581 LEnvironment* LChunkBuilderBase::CreateEnvironment(
 582     HEnvironment* hydrogen_env, int* argument_index_accumulator,
 583     ZoneList<HValue*>* objects_to_materialize) {
 584   if (hydrogen_env == NULL) return NULL;
 585
 586   LEnvironment* outer =
 587       CreateEnvironment(hydrogen_env->outer(), argument_index_accumulator,
 588                         objects_to_materialize);
 589   BailoutId ast_id = hydrogen_env->ast_id();
 590   DCHECK(!ast_id.IsNone() ||
 591          hydrogen_env->frame_type() != JS_FUNCTION);
 592
 593   int omitted_count = (hydrogen_env->frame_type() == JS_FUNCTION)
 594                           ? 0
 595                           : hydrogen_env->specials_count();
 596
 597   int value_count = hydrogen_env->length() - omitted_count;
 598   LEnvironment* result =
 599       new(zone()) LEnvironment(hydrogen_env->closure(),
 600                                hydrogen_env->frame_type(),
 601                                ast_id,
 602                                hydrogen_env->parameter_count(),
 603                                argument_count_,
 604                                value_count,
 605                                outer,
 606                                hydrogen_env->entry(),
 607                                zone());
 608   int argument_index = *argument_index_accumulator;
 609
 610   // Store the environment description into the environment
 611   // (with holes for nested objects)
 612   for (int i = 0; i < hydrogen_env->length(); ++i) {
 613     if (hydrogen_env->is_special_index(i) &&
 614         hydrogen_env->frame_type() != JS_FUNCTION) {
 615       continue;
 616     }
 617     LOperand* op;
 618     HValue* value = hydrogen_env->values()->at(i);
 619     CHECK(!value->IsPushArguments());  // Do not deopt outgoing arguments
 620     if (value->IsArgumentsObject() || value->IsCapturedObject()) {
 621       op = LEnvironment::materialization_marker();
 622     } else {
 623       op = UseAny(value);
 624     }
 625     result->AddValue(op,
 626                      value->representation(),
 627                      value->CheckFlag(HInstruction::kUint32));
 628   }
 629
 630   // Recursively store the nested objects into the environment
 631   for (int i = 0; i < hydrogen_env->length(); ++i) {
 632     if (hydrogen_env->is_special_index(i)) continue;
 633
 634     HValue* value = hydrogen_env->values()->at(i);
 635     if (value->IsArgumentsObject() || value->IsCapturedObject()) {
 636       AddObjectToMaterialize(value, objects_to_materialize, result);
 637     }
 638   }
 639
 640   if (hydrogen_env->frame_type() == JS_FUNCTION) {
 641     *argument_index_accumulator = argument_index;
 642   }
 643
 644   return result;
 645 }
 646
 647
 648 // Add an object to the supplied environment and object materialization list.
 649 //
 650 // Notes:
 651 //
 652 // We are building three lists here:
 653 //
 654 // 1. In the result->object_mapping_ list (added to by the
 655 //    LEnvironment::Add*Object methods), we store the lengths (number
 656 //    of fields) of the captured objects in depth-first traversal order, or
 657 //    in case of duplicated objects, we store the index to the duplicate object
 658 //    (with a tag to differentiate between captured and duplicated objects).
 659 //
 660 // 2. The object fields are stored in the result->values_ list
 661 //    (added to by the LEnvironment.AddValue method) sequentially as lists
 662 //    of fields with holes for nested objects (the holes will be expanded
 663 //    later by LCodegen::AddToTranslation according to the
 664 //    LEnvironment.object_mapping_ list).
 665 //
 666 // 3. The auxiliary objects_to_materialize array stores the hydrogen values
 667 //    in the same order as result->object_mapping_ list. This is used
 668 //    to detect duplicate values and calculate the corresponding object index.
 669 void LChunkBuilderBase::AddObjectToMaterialize(HValue* value,
 670     ZoneList<HValue*>* objects_to_materialize, LEnvironment* result) {
 671   int object_index = objects_to_materialize->length();
 672   // Store the hydrogen value into the de-duplication array
 673   objects_to_materialize->Add(value, zone());
 674   // Find out whether we are storing a duplicated value
 675   int previously_materialized_object = -1;
 676   for (int prev = 0; prev < object_index; ++prev) {
 677     if (objects_to_materialize->at(prev) == value) {
 678       previously_materialized_object = prev;
 679       break;
 680     }
 681   }
 682   // Store the captured object length (or duplicated object index)
 683   // into the environment. For duplicated objects, we stop here.
 684   int length = value->OperandCount();
 685   bool is_arguments = value->IsArgumentsObject();
 686   if (previously_materialized_object >= 0) {
 687     result->AddDuplicateObject(previously_materialized_object);
 688     return;
 689   } else {
 690     result->AddNewObject(is_arguments ? length - 1 : length, is_arguments);
 691   }
 692   // Store the captured object's fields into the environment
 693   for (int i = is_arguments ? 1 : 0; i < length; ++i) {
 694     LOperand* op;
 695     HValue* arg_value = value->OperandAt(i);
 696     if (arg_value->IsArgumentsObject() || arg_value->IsCapturedObject()) {
 697       // Insert a hole for nested objects
 698       op = LEnvironment::materialization_marker();
 699     } else {
 700       DCHECK(!arg_value->IsPushArguments());
 701       // For ordinary values, tell the register allocator we need the value
 702       // to be alive here
 703       op = UseAny(arg_value);
 704     }
 705     result->AddValue(op,
 706                      arg_value->representation(),
 707                      arg_value->CheckFlag(HInstruction::kUint32));
 708   }
 709   // Recursively store all the nested captured objects into the environment
 710   for (int i = is_arguments ? 1 : 0; i < length; ++i) {
 711     HValue* arg_value = value->OperandAt(i);
 712     if (arg_value->IsArgumentsObject() || arg_value->IsCapturedObject()) {
 713       AddObjectToMaterialize(arg_value, objects_to_materialize, result);
 714     }
 715   }
 716 }
 717
 718
 719 LPhase::~LPhase() {
 720   if (ShouldProduceTraceOutput()) {
 721     isolate()->GetHTracer()->TraceLithium(name(), chunk_);
 722   }
 723 }
 724
 725
 726 } }  // namespace v8::internal