deps/v8/src/code-stubs-hydrogen.cc

   1 // Copyright 2012 the V8 project authors. All rights reserved.
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  27
  28 #include "v8.h"
  29
  30 #include "code-stubs.h"
  31 #include "hydrogen.h"
  32 #include "lithium.h"
  33
  34 namespace v8 {
  35 namespace internal {
  36
  37
  38 static LChunk* OptimizeGraph(HGraph* graph) {
  39   DisallowHeapAllocation no_allocation;
  40   DisallowHandleAllocation no_handles;
  41   DisallowHandleDereference no_deref;
  42
  43   ASSERT(graph != NULL);
  44   SmartArrayPointer<char> bailout_reason;
  45   if (!graph->Optimize(&bailout_reason)) {
  46     FATAL(bailout_reason.is_empty() ? "unknown" : *bailout_reason);
  47   }
  48   LChunk* chunk = LChunk::NewChunk(graph);
  49   if (chunk == NULL) {
  50     FATAL(graph->info()->bailout_reason());
  51   }
  52   return chunk;
  53 }
  54
  55
  56 class CodeStubGraphBuilderBase : public HGraphBuilder {
  57  public:
  58   CodeStubGraphBuilderBase(Isolate* isolate, HydrogenCodeStub* stub)
  59       : HGraphBuilder(&info_),
  60         arguments_length_(NULL),
  61         info_(stub, isolate),
  62         context_(NULL) {
  63     descriptor_ = stub->GetInterfaceDescriptor(isolate);
  64     parameters_.Reset(new HParameter*[descriptor_->register_param_count_]);
  65   }
  66   virtual bool BuildGraph();
  67
  68  protected:
  69   virtual HValue* BuildCodeStub() = 0;
  70   HParameter* GetParameter(int parameter) {
  71     ASSERT(parameter < descriptor_->register_param_count_);
  72     return parameters_[parameter];
  73   }
  74   HValue* GetArgumentsLength() {
  75     // This is initialized in BuildGraph()
  76     ASSERT(arguments_length_ != NULL);
  77     return arguments_length_;
  78   }
  79   CompilationInfo* info() { return &info_; }
  80   HydrogenCodeStub* stub() { return info_.code_stub(); }
  81   HContext* context() { return context_; }
  82   Isolate* isolate() { return info_.isolate(); }
  83
  84   class ArrayContextChecker {
  85    public:
  86     ArrayContextChecker(HGraphBuilder* builder, HValue* constructor,
  87                         HValue* array_function)
  88         : checker_(builder) {
  89       checker_.If<HCompareObjectEqAndBranch, HValue*>(constructor,
  90                                                       array_function);
  91       checker_.Then();
  92     }
  93
  94     ~ArrayContextChecker() {
  95       checker_.ElseDeopt();
  96       checker_.End();
  97     }
  98    private:
  99     IfBuilder checker_;
 100   };
 101
 102   enum ArgumentClass {
 103     NONE,
 104     SINGLE,
 105     MULTIPLE
 106   };
 107
 108   HValue* BuildArrayConstructor(ElementsKind kind,
 109                                 bool disable_allocation_sites,
 110                                 ArgumentClass argument_class);
 111   HValue* BuildInternalArrayConstructor(ElementsKind kind,
 112                                         ArgumentClass argument_class);
 113
 114  private:
 115   HValue* BuildArraySingleArgumentConstructor(JSArrayBuilder* builder);
 116   HValue* BuildArrayNArgumentsConstructor(JSArrayBuilder* builder,
 117                                           ElementsKind kind);
 118
 119   SmartArrayPointer<HParameter*> parameters_;
 120   HValue* arguments_length_;
 121   CompilationInfoWithZone info_;
 122   CodeStubInterfaceDescriptor* descriptor_;
 123   HContext* context_;
 124 };
 125
 126
 127 bool CodeStubGraphBuilderBase::BuildGraph() {
 128   // Update the static counter each time a new code stub is generated.
 129   isolate()->counters()->code_stubs()->Increment();
 130
 131   if (FLAG_trace_hydrogen) {
 132     const char* name = CodeStub::MajorName(stub()->MajorKey(), false);
 133     PrintF("-----------------------------------------------------------\n");
 134     PrintF("Compiling stub %s using hydrogen\n", name);
 135     isolate()->GetHTracer()->TraceCompilation(&info_);
 136   }
 137
 138   Zone* zone = this->zone();
 139   int param_count = descriptor_->register_param_count_;
 140   HEnvironment* start_environment = graph()->start_environment();
 141   HBasicBlock* next_block = CreateBasicBlock(start_environment);
 142   current_block()->Goto(next_block);
 143   next_block->SetJoinId(BailoutId::StubEntry());
 144   set_current_block(next_block);
 145
 146   HConstant* undefined_constant = new(zone) HConstant(
 147       isolate()->factory()->undefined_value(), Representation::Tagged());
 148   AddInstruction(undefined_constant);
 149   graph()->set_undefined_constant(undefined_constant);
 150
 151   for (int i = 0; i < param_count; ++i) {
 152     HParameter* param =
 153         new(zone) HParameter(i, HParameter::REGISTER_PARAMETER);
 154     AddInstruction(param);
 155     start_environment->Bind(i, param);
 156     parameters_[i] = param;
 157   }
 158
 159   HInstruction* stack_parameter_count;
 160   if (descriptor_->stack_parameter_count_ != NULL) {
 161     ASSERT(descriptor_->environment_length() == (param_count + 1));
 162     stack_parameter_count = new(zone) HParameter(param_count,
 163                                                  HParameter::REGISTER_PARAMETER,
 164                                                  Representation::Integer32());
 165     stack_parameter_count->set_type(HType::Smi());
 166     // It's essential to bind this value to the environment in case of deopt.
 167     AddInstruction(stack_parameter_count);
 168     start_environment->Bind(param_count, stack_parameter_count);
 169     arguments_length_ = stack_parameter_count;
 170   } else {
 171     ASSERT(descriptor_->environment_length() == param_count);
 172     stack_parameter_count = graph()->GetConstantMinus1();
 173     arguments_length_ = graph()->GetConstant0();
 174   }
 175
 176   context_ = new(zone) HContext();
 177   AddInstruction(context_);
 178   start_environment->BindContext(context_);
 179
 180   AddSimulate(BailoutId::StubEntry());
 181
 182   NoObservableSideEffectsScope no_effects(this);
 183
 184   HValue* return_value = BuildCodeStub();
 185
 186   // We might have extra expressions to pop from the stack in addition to the
 187   // arguments above.
 188   HInstruction* stack_pop_count = stack_parameter_count;
 189   if (descriptor_->function_mode_ == JS_FUNCTION_STUB_MODE) {
 190     if (!stack_parameter_count->IsConstant() &&
 191         descriptor_->hint_stack_parameter_count_ < 0) {
 192       HInstruction* amount = graph()->GetConstant1();
 193       stack_pop_count = AddInstruction(
 194           HAdd::New(zone, context_, stack_parameter_count, amount));
 195       stack_pop_count->ChangeRepresentation(Representation::Integer32());
 196       stack_pop_count->ClearFlag(HValue::kCanOverflow);
 197     } else {
 198       int count = descriptor_->hint_stack_parameter_count_;
 199       stack_pop_count = AddInstruction(new(zone)
 200           HConstant(count, Representation::Integer32()));
 201     }
 202   }
 203
 204   if (current_block() != NULL) {
 205     HReturn* hreturn_instruction = new(zone) HReturn(return_value,
 206                                                      context_,
 207                                                      stack_pop_count);
 208     current_block()->Finish(hreturn_instruction);
 209     set_current_block(NULL);
 210   }
 211   return true;
 212 }
 213
 214
 215 template <class Stub>
 216 class CodeStubGraphBuilder: public CodeStubGraphBuilderBase {
 217  public:
 218   explicit CodeStubGraphBuilder(Stub* stub)
 219       : CodeStubGraphBuilderBase(Isolate::Current(), stub) {}
 220
 221  protected:
 222   virtual HValue* BuildCodeStub() {
 223     if (casted_stub()->IsUninitialized()) {
 224       return BuildCodeUninitializedStub();
 225     } else {
 226       return BuildCodeInitializedStub();
 227     }
 228   }
 229
 230   virtual HValue* BuildCodeInitializedStub() {
 231     UNIMPLEMENTED();
 232     return NULL;
 233   }
 234
 235   virtual HValue* BuildCodeUninitializedStub() {
 236     // Force a deopt that falls back to the runtime.
 237     HValue* undefined = graph()->GetConstantUndefined();
 238     IfBuilder builder(this);
 239     builder.IfNot<HCompareObjectEqAndBranch, HValue*>(undefined, undefined);
 240     builder.Then();
 241     builder.ElseDeopt();
 242     return undefined;
 243   }
 244
 245   Stub* casted_stub() { return static_cast<Stub*>(stub()); }
 246 };
 247
 248
 249 Handle<Code> HydrogenCodeStub::GenerateLightweightMissCode(Isolate* isolate) {
 250   Factory* factory = isolate->factory();
 251
 252   // Generate the new code.
 253   MacroAssembler masm(isolate, NULL, 256);
 254
 255   {
 256     // Update the static counter each time a new code stub is generated.
 257     isolate->counters()->code_stubs()->Increment();
 258
 259     // Nested stubs are not allowed for leaves.
 260     AllowStubCallsScope allow_scope(&masm, false);
 261
 262     // Generate the code for the stub.
 263     masm.set_generating_stub(true);
 264     NoCurrentFrameScope scope(&masm);
 265     GenerateLightweightMiss(&masm);
 266   }
 267
 268   // Create the code object.
 269   CodeDesc desc;
 270   masm.GetCode(&desc);
 271
 272   // Copy the generated code into a heap object.
 273   Code::Flags flags = Code::ComputeFlags(
 274       GetCodeKind(),
 275       GetICState(),
 276       GetExtraICState(),
 277       GetStubType(),
 278       GetStubFlags());
 279   Handle<Code> new_object = factory->NewCode(
 280       desc, flags, masm.CodeObject(), NeedsImmovableCode());
 281   return new_object;
 282 }
 283
 284
 285 template <class Stub>
 286 static Handle<Code> DoGenerateCode(Stub* stub) {
 287   Isolate* isolate = Isolate::Current();
 288   CodeStub::Major  major_key =
 289       static_cast<HydrogenCodeStub*>(stub)->MajorKey();
 290   CodeStubInterfaceDescriptor* descriptor =
 291       isolate->code_stub_interface_descriptor(major_key);
 292   if (descriptor->register_param_count_ < 0) {
 293     stub->InitializeInterfaceDescriptor(isolate, descriptor);
 294   }
 295
 296   // If we are uninitialized we can use a light-weight stub to enter
 297   // the runtime that is significantly faster than using the standard
 298   // stub-failure deopt mechanism.
 299   if (stub->IsUninitialized() && descriptor->has_miss_handler()) {
 300     ASSERT(descriptor->stack_parameter_count_ == NULL);
 301     return stub->GenerateLightweightMissCode(isolate);
 302   }
 303   CodeStubGraphBuilder<Stub> builder(stub);
 304   LChunk* chunk = OptimizeGraph(builder.CreateGraph());
 305   return chunk->Codegen();
 306 }
 307
 308
 309 template <>
 310 HValue* CodeStubGraphBuilder<FastCloneShallowArrayStub>::BuildCodeStub() {
 311   Zone* zone = this->zone();
 312   Factory* factory = isolate()->factory();
 313   HValue* undefined = graph()->GetConstantUndefined();
 314   AllocationSiteMode alloc_site_mode = casted_stub()->allocation_site_mode();
 315   FastCloneShallowArrayStub::Mode mode = casted_stub()->mode();
 316   int length = casted_stub()->length();
 317
 318   HInstruction* boilerplate =
 319       AddInstruction(new(zone) HLoadKeyed(GetParameter(0),
 320                                           GetParameter(1),
 321                                           NULL,
 322                                           FAST_ELEMENTS));
 323
 324   IfBuilder checker(this);
 325   checker.IfNot<HCompareObjectEqAndBranch, HValue*>(boilerplate, undefined);
 326   checker.Then();
 327
 328   if (mode == FastCloneShallowArrayStub::CLONE_ANY_ELEMENTS) {
 329     HValue* elements = AddLoadElements(boilerplate);
 330
 331     IfBuilder if_fixed_cow(this);
 332     if_fixed_cow.IfCompareMap(elements, factory->fixed_cow_array_map());
 333     if_fixed_cow.Then();
 334     environment()->Push(BuildCloneShallowArray(context(),
 335                                                boilerplate,
 336                                                alloc_site_mode,
 337                                                FAST_ELEMENTS,
 338                                                0/*copy-on-write*/));
 339     if_fixed_cow.Else();
 340
 341     IfBuilder if_fixed(this);
 342     if_fixed.IfCompareMap(elements, factory->fixed_array_map());
 343     if_fixed.Then();
 344     environment()->Push(BuildCloneShallowArray(context(),
 345                                                boilerplate,
 346                                                alloc_site_mode,
 347                                                FAST_ELEMENTS,
 348                                                length));
 349     if_fixed.Else();
 350     environment()->Push(BuildCloneShallowArray(context(),
 351                                                boilerplate,
 352                                                alloc_site_mode,
 353                                                FAST_DOUBLE_ELEMENTS,
 354                                                length));
 355   } else {
 356     ElementsKind elements_kind = casted_stub()->ComputeElementsKind();
 357     environment()->Push(BuildCloneShallowArray(context(),
 358                                                boilerplate,
 359                                                alloc_site_mode,
 360                                                elements_kind,
 361                                                length));
 362   }
 363
 364   HValue* result = environment()->Pop();
 365   checker.ElseDeopt();
 366   return result;
 367 }
 368
 369
 370 Handle<Code> FastCloneShallowArrayStub::GenerateCode() {
 371   return DoGenerateCode(this);
 372 }
 373
 374
 375 template <>
 376 HValue* CodeStubGraphBuilder<FastCloneShallowObjectStub>::BuildCodeStub() {
 377   Zone* zone = this->zone();
 378   HValue* undefined = graph()->GetConstantUndefined();
 379
 380   HInstruction* boilerplate =
 381       AddInstruction(new(zone) HLoadKeyed(GetParameter(0),
 382                                           GetParameter(1),
 383                                           NULL,
 384                                           FAST_ELEMENTS));
 385
 386   IfBuilder checker(this);
 387   checker.IfNot<HCompareObjectEqAndBranch, HValue*>(boilerplate, undefined);
 388   checker.And();
 389
 390   int size = JSObject::kHeaderSize + casted_stub()->length() * kPointerSize;
 391   HValue* boilerplate_size =
 392       AddInstruction(new(zone) HInstanceSize(boilerplate));
 393   HValue* size_in_words =
 394       AddInstruction(new(zone) HConstant(size >> kPointerSizeLog2,
 395                                          Representation::Integer32()));
 396   checker.IfCompare(boilerplate_size, size_in_words, Token::EQ);
 397   checker.Then();
 398
 399   HValue* size_in_bytes =
 400       AddInstruction(new(zone) HConstant(size, Representation::Integer32()));
 401   HAllocate::Flags flags = HAllocate::CAN_ALLOCATE_IN_NEW_SPACE;
 402   if (isolate()->heap()->ShouldGloballyPretenure()) {
 403     flags = static_cast<HAllocate::Flags>(
 404        flags | HAllocate::CAN_ALLOCATE_IN_OLD_POINTER_SPACE);
 405   }
 406
 407   HInstruction* object = AddInstruction(new(zone)
 408       HAllocate(context(), size_in_bytes, HType::JSObject(), flags));
 409
 410   for (int i = 0; i < size; i += kPointerSize) {
 411     HObjectAccess access = HObjectAccess::ForJSObjectOffset(i);
 412     AddStore(object, access, AddLoad(boilerplate, access));
 413   }
 414
 415   checker.ElseDeopt();
 416   return object;
 417 }
 418
 419
 420 Handle<Code> FastCloneShallowObjectStub::GenerateCode() {
 421   return DoGenerateCode(this);
 422 }
 423
 424
 425 template <>
 426 HValue* CodeStubGraphBuilder<KeyedLoadFastElementStub>::BuildCodeStub() {
 427   HInstruction* load = BuildUncheckedMonomorphicElementAccess(
 428       GetParameter(0), GetParameter(1), NULL, NULL,
 429       casted_stub()->is_js_array(), casted_stub()->elements_kind(),
 430       false, NEVER_RETURN_HOLE, STANDARD_STORE);
 431   return load;
 432 }
 433
 434
 435 Handle<Code> KeyedLoadFastElementStub::GenerateCode() {
 436   return DoGenerateCode(this);
 437 }
 438
 439
 440 template<>
 441 HValue* CodeStubGraphBuilder<LoadFieldStub>::BuildCodeStub() {
 442   HObjectAccess access = casted_stub()->is_inobject() ?
 443       HObjectAccess::ForJSObjectOffset(casted_stub()->offset()) :
 444       HObjectAccess::ForBackingStoreOffset(casted_stub()->offset());
 445   return AddInstruction(BuildLoadNamedField(GetParameter(0), access,
 446       casted_stub()->representation()));
 447 }
 448
 449
 450 Handle<Code> LoadFieldStub::GenerateCode() {
 451   return DoGenerateCode(this);
 452 }
 453
 454
 455 template<>
 456 HValue* CodeStubGraphBuilder<KeyedLoadFieldStub>::BuildCodeStub() {
 457   HObjectAccess access = casted_stub()->is_inobject() ?
 458       HObjectAccess::ForJSObjectOffset(casted_stub()->offset()) :
 459       HObjectAccess::ForBackingStoreOffset(casted_stub()->offset());
 460   return AddInstruction(BuildLoadNamedField(GetParameter(0), access,
 461       casted_stub()->representation()));
 462 }
 463
 464
 465 Handle<Code> KeyedLoadFieldStub::GenerateCode() {
 466   return DoGenerateCode(this);
 467 }
 468
 469
 470 template <>
 471 HValue* CodeStubGraphBuilder<KeyedStoreFastElementStub>::BuildCodeStub() {
 472   BuildUncheckedMonomorphicElementAccess(
 473       GetParameter(0), GetParameter(1), GetParameter(2), NULL,
 474       casted_stub()->is_js_array(), casted_stub()->elements_kind(),
 475       true, NEVER_RETURN_HOLE, casted_stub()->store_mode());
 476
 477   return GetParameter(2);
 478 }
 479
 480
 481 Handle<Code> KeyedStoreFastElementStub::GenerateCode() {
 482   return DoGenerateCode(this);
 483 }
 484
 485
 486 template <>
 487 HValue* CodeStubGraphBuilder<TransitionElementsKindStub>::BuildCodeStub() {
 488   Zone* zone = this->zone();
 489
 490   HValue* js_array = GetParameter(0);
 491   HValue* map = GetParameter(1);
 492
 493   info()->MarkAsSavesCallerDoubles();
 494
 495   AddInstruction(new(zone) HTrapAllocationMemento(js_array));
 496
 497   HInstruction* array_length =
 498       AddLoad(js_array, HObjectAccess::ForArrayLength());
 499   array_length->set_type(HType::Smi());
 500
 501   ElementsKind to_kind = casted_stub()->to_kind();
 502   BuildNewSpaceArrayCheck(array_length, to_kind);
 503
 504   IfBuilder if_builder(this);
 505
 506   if_builder.IfCompare(array_length, graph()->GetConstant0(), Token::EQ);
 507   if_builder.Then();
 508
 509   // Nothing to do, just change the map.
 510
 511   if_builder.Else();
 512
 513   HInstruction* elements = AddLoadElements(js_array);
 514
 515   HInstruction* elements_length =
 516       AddInstruction(new(zone) HFixedArrayBaseLength(elements));
 517
 518   HValue* new_elements = BuildAllocateElementsAndInitializeElementsHeader(
 519       context(), to_kind, elements_length);
 520
 521   BuildCopyElements(context(), elements,
 522                     casted_stub()->from_kind(), new_elements,
 523                     to_kind, array_length, elements_length);
 524
 525   AddStore(js_array, HObjectAccess::ForElementsPointer(), new_elements);
 526
 527   if_builder.End();
 528
 529   AddStore(js_array, HObjectAccess::ForMap(), map);
 530
 531   return js_array;
 532 }
 533
 534
 535 Handle<Code> TransitionElementsKindStub::GenerateCode() {
 536   return DoGenerateCode(this);
 537 }
 538
 539 HValue* CodeStubGraphBuilderBase::BuildArrayConstructor(
 540     ElementsKind kind, bool disable_allocation_sites,
 541     ArgumentClass argument_class) {
 542   HValue* constructor = GetParameter(ArrayConstructorStubBase::kConstructor);
 543   HValue* property_cell = GetParameter(ArrayConstructorStubBase::kPropertyCell);
 544   HInstruction* array_function = BuildGetArrayFunction(context());
 545
 546   ArrayContextChecker(this, constructor, array_function);
 547   JSArrayBuilder array_builder(this, kind, property_cell,
 548                                disable_allocation_sites);
 549   HValue* result = NULL;
 550   switch (argument_class) {
 551     case NONE:
 552       result = array_builder.AllocateEmptyArray();
 553       break;
 554     case SINGLE:
 555       result = BuildArraySingleArgumentConstructor(&array_builder);
 556       break;
 557     case MULTIPLE:
 558       result = BuildArrayNArgumentsConstructor(&array_builder, kind);
 559       break;
 560   }
 561   return result;
 562 }
 563
 564
 565 HValue* CodeStubGraphBuilderBase::BuildInternalArrayConstructor(
 566     ElementsKind kind, ArgumentClass argument_class) {
 567   HValue* constructor = GetParameter(
 568       InternalArrayConstructorStubBase::kConstructor);
 569   JSArrayBuilder array_builder(this, kind, constructor);
 570
 571   HValue* result = NULL;
 572   switch (argument_class) {
 573     case NONE:
 574       result = array_builder.AllocateEmptyArray();
 575       break;
 576     case SINGLE:
 577       result = BuildArraySingleArgumentConstructor(&array_builder);
 578       break;
 579     case MULTIPLE:
 580       result = BuildArrayNArgumentsConstructor(&array_builder, kind);
 581       break;
 582   }
 583   return result;
 584 }
 585
 586
 587 HValue* CodeStubGraphBuilderBase::BuildArraySingleArgumentConstructor(
 588     JSArrayBuilder* array_builder) {
 589   // Smi check and range check on the input arg.
 590   HValue* constant_one = graph()->GetConstant1();
 591   HValue* constant_zero = graph()->GetConstant0();
 592
 593   HInstruction* elements = AddInstruction(
 594       new(zone()) HArgumentsElements(false));
 595   HInstruction* argument = AddInstruction(
 596       new(zone()) HAccessArgumentsAt(elements, constant_one, constant_zero));
 597
 598   HConstant* max_alloc_length =
 599       new(zone()) HConstant(JSObject::kInitialMaxFastElementArray);
 600   AddInstruction(max_alloc_length);
 601   const int initial_capacity = JSArray::kPreallocatedArrayElements;
 602   HConstant* initial_capacity_node = new(zone()) HConstant(initial_capacity);
 603   AddInstruction(initial_capacity_node);
 604
 605   HBoundsCheck* checked_arg = AddBoundsCheck(argument, max_alloc_length);
 606   IfBuilder if_builder(this);
 607   if_builder.IfCompare(checked_arg, constant_zero, Token::EQ);
 608   if_builder.Then();
 609   Push(initial_capacity_node);  // capacity
 610   Push(constant_zero);  // length
 611   if_builder.Else();
 612   Push(checked_arg);  // capacity
 613   Push(checked_arg);  // length
 614   if_builder.End();
 615
 616   // Figure out total size
 617   HValue* length = Pop();
 618   HValue* capacity = Pop();
 619   return array_builder->AllocateArray(capacity, length, true);
 620 }
 621
 622
 623 HValue* CodeStubGraphBuilderBase::BuildArrayNArgumentsConstructor(
 624     JSArrayBuilder* array_builder, ElementsKind kind) {
 625   // We need to fill with the hole if it's a smi array in the multi-argument
 626   // case because we might have to bail out while copying arguments into
 627   // the array because they aren't compatible with a smi array.
 628   // If it's a double array, no problem, and if it's fast then no
 629   // problem either because doubles are boxed.
 630   HValue* length = GetArgumentsLength();
 631   bool fill_with_hole = IsFastSmiElementsKind(kind);
 632   HValue* new_object = array_builder->AllocateArray(length,
 633                                                     length,
 634                                                     fill_with_hole);
 635   HValue* elements = array_builder->GetElementsLocation();
 636   ASSERT(elements != NULL);
 637
 638   // Now populate the elements correctly.
 639   LoopBuilder builder(this,
 640                       context(),
 641                       LoopBuilder::kPostIncrement);
 642   HValue* start = graph()->GetConstant0();
 643   HValue* key = builder.BeginBody(start, length, Token::LT);
 644   HInstruction* argument_elements = AddInstruction(
 645       new(zone()) HArgumentsElements(false));
 646   HInstruction* argument = AddInstruction(new(zone()) HAccessArgumentsAt(
 647       argument_elements, length, key));
 648
 649   AddInstruction(new(zone()) HStoreKeyed(elements, key, argument, kind));
 650   builder.EndBody();
 651   return new_object;
 652 }
 653
 654
 655 template <>
 656 HValue* CodeStubGraphBuilder<ArrayNoArgumentConstructorStub>::BuildCodeStub() {
 657   ElementsKind kind = casted_stub()->elements_kind();
 658   bool disable_allocation_sites = casted_stub()->disable_allocation_sites();
 659   return BuildArrayConstructor(kind, disable_allocation_sites, NONE);
 660 }
 661
 662
 663 Handle<Code> ArrayNoArgumentConstructorStub::GenerateCode() {
 664   return DoGenerateCode(this);
 665 }
 666
 667
 668 template <>
 669 HValue* CodeStubGraphBuilder<ArraySingleArgumentConstructorStub>::
 670     BuildCodeStub() {
 671   ElementsKind kind = casted_stub()->elements_kind();
 672   bool disable_allocation_sites = casted_stub()->disable_allocation_sites();
 673   return BuildArrayConstructor(kind, disable_allocation_sites, SINGLE);
 674 }
 675
 676
 677 Handle<Code> ArraySingleArgumentConstructorStub::GenerateCode() {
 678   return DoGenerateCode(this);
 679 }
 680
 681
 682 template <>
 683 HValue* CodeStubGraphBuilder<ArrayNArgumentsConstructorStub>::BuildCodeStub() {
 684   ElementsKind kind = casted_stub()->elements_kind();
 685   bool disable_allocation_sites = casted_stub()->disable_allocation_sites();
 686   return BuildArrayConstructor(kind, disable_allocation_sites, MULTIPLE);
 687 }
 688
 689
 690 Handle<Code> ArrayNArgumentsConstructorStub::GenerateCode() {
 691   return DoGenerateCode(this);
 692 }
 693
 694
 695 template <>
 696 HValue* CodeStubGraphBuilder<InternalArrayNoArgumentConstructorStub>::
 697     BuildCodeStub() {
 698   ElementsKind kind = casted_stub()->elements_kind();
 699   return BuildInternalArrayConstructor(kind, NONE);
 700 }
 701
 702
 703 Handle<Code> InternalArrayNoArgumentConstructorStub::GenerateCode() {
 704   return DoGenerateCode(this);
 705 }
 706
 707
 708 template <>
 709 HValue* CodeStubGraphBuilder<InternalArraySingleArgumentConstructorStub>::
 710     BuildCodeStub() {
 711   ElementsKind kind = casted_stub()->elements_kind();
 712   return BuildInternalArrayConstructor(kind, SINGLE);
 713 }
 714
 715
 716 Handle<Code> InternalArraySingleArgumentConstructorStub::GenerateCode() {
 717   return DoGenerateCode(this);
 718 }
 719
 720
 721 template <>
 722 HValue* CodeStubGraphBuilder<InternalArrayNArgumentsConstructorStub>::
 723     BuildCodeStub() {
 724   ElementsKind kind = casted_stub()->elements_kind();
 725   return BuildInternalArrayConstructor(kind, MULTIPLE);
 726 }
 727
 728
 729 Handle<Code> InternalArrayNArgumentsConstructorStub::GenerateCode() {
 730   return DoGenerateCode(this);
 731 }
 732
 733
 734 template <>
 735 HValue* CodeStubGraphBuilder<CompareNilICStub>::BuildCodeInitializedStub() {
 736   CompareNilICStub* stub = casted_stub();
 737   HIfContinuation continuation;
 738   Handle<Map> sentinel_map(graph()->isolate()->heap()->meta_map());
 739   BuildCompareNil(GetParameter(0),
 740                   stub->GetTypes(), sentinel_map,
 741                   RelocInfo::kNoPosition, &continuation);
 742   IfBuilder if_nil(this, &continuation);
 743   if_nil.Then();
 744   if (continuation.IsFalseReachable()) {
 745     if_nil.Else();
 746     if_nil.Return(graph()->GetConstant0());
 747   }
 748   if_nil.End();
 749   return continuation.IsTrueReachable()
 750       ? graph()->GetConstant1()
 751       : graph()->GetConstantUndefined();
 752 }
 753
 754
 755 Handle<Code> CompareNilICStub::GenerateCode() {
 756   return DoGenerateCode(this);
 757 }
 758
 759
 760 template <>
 761 HValue* CodeStubGraphBuilder<ToBooleanStub>::BuildCodeInitializedStub() {
 762   ToBooleanStub* stub = casted_stub();
 763
 764   IfBuilder if_true(this);
 765   if_true.If<HBranch>(GetParameter(0), stub->GetTypes());
 766   if_true.Then();
 767     if_true.Return(graph()->GetConstant1());
 768   if_true.Else();
 769   if_true.End();
 770   return graph()->GetConstant0();
 771 }
 772
 773
 774 Handle<Code> ToBooleanStub::GenerateCode() {
 775   return DoGenerateCode(this);
 776 }
 777
 778
 779 } }  // namespace v8::internal