text: // Copyright 2014 the V8 project authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  
  #include "src/v8.h"
  
  #if V8_TARGET_ARCH_MIPS
  
  #include "src/ic/call-optimization.h"
  #include "src/ic/handler-compiler.h"
  #include "src/ic/ic.h"
  
  namespace v8 {
  namespace internal {
  
  #define __ ACCESS_MASM(masm)
  
  
  void NamedLoadHandlerCompiler::GenerateLoadViaGetter(
      MacroAssembler* masm, Handle<Map> map, Register receiver, Register holder,
      int accessor_index, int expected_arguments, Register scratch) {
    // ----------- S t a t e -------------
    //  -- a0    : receiver
    //  -- a2    : name
    //  -- ra    : return address
    // -----------------------------------
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
  
      if (accessor_index >= 0) {
        DCHECK(!holder.is(scratch));
        DCHECK(!receiver.is(scratch));
        // Call the JavaScript getter with the receiver on the stack.
        if (map->IsJSGlobalObjectMap()) {
          // Swap in the global receiver.
          __ lw(scratch,
                FieldMemOperand(receiver, JSGlobalObject::kGlobalProxyOffset));
          receiver = scratch;
        }
        __ push(receiver);
        ParameterCount actual(0);
        ParameterCount expected(expected_arguments);
        __ LoadAccessor(a1, holder, accessor_index, ACCESSOR_GETTER);
        __ InvokeFunction(a1, expected, actual, CALL_FUNCTION, NullCallWrapper());
      } else {
        // If we generate a global code snippet for deoptimization only, remember
        // the place to continue after deoptimization.
        masm->isolate()->heap()->SetGetterStubDeoptPCOffset(masm->pc_offset());
      }
  
      // Restore context register.
      __ lw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
    }
    __ Ret();
  }
  
  
  void NamedStoreHandlerCompiler::GenerateStoreViaSetter(
      MacroAssembler* masm, Handle<Map> map, Register receiver, Register holder,
      int accessor_index, int expected_arguments, Register scratch) {
    // ----------- S t a t e -------------
    //  -- ra    : return address
    // -----------------------------------
    {
      FrameScope scope(masm, StackFrame::INTERNAL);
  
      // Save value register, so we can restore it later.
      __ push(value());
  
      if (accessor_index >= 0) {
        DCHECK(!holder.is(scratch));
        DCHECK(!receiver.is(scratch));
        DCHECK(!value().is(scratch));
        // Call the JavaScript setter with receiver and value on the stack.
        if (map->IsJSGlobalObjectMap()) {
          // Swap in the global receiver.
          __ lw(scratch,
                FieldMemOperand(receiver, JSGlobalObject::kGlobalProxyOffset));
          receiver = scratch;
        }
        __ Push(receiver, value());
        ParameterCount actual(1);
        ParameterCount expected(expected_arguments);
        __ LoadAccessor(a1, holder, accessor_index, ACCESSOR_SETTER);
        __ InvokeFunction(a1, expected, actual, CALL_FUNCTION, NullCallWrapper());
      } else {
        // If we generate a global code snippet for deoptimization only, remember
        // the place to continue after deoptimization.
        masm->isolate()->heap()->SetSetterStubDeoptPCOffset(masm->pc_offset());
      }
  
      // We have to return the passed value, not the return value of the setter.
      __ pop(v0);
  
      // Restore context register.
      __ lw(cp, MemOperand(fp, StandardFrameConstants::kContextOffset));
    }
    __ Ret();
  }
  
  
  void PropertyHandlerCompiler::PushVectorAndSlot(Register vector,
                                                  Register slot) {
    MacroAssembler* masm = this->masm();
    __ Push(vector, slot);
  }
  
  
  void PropertyHandlerCompiler::PopVectorAndSlot(Register vector, Register slot) {
    MacroAssembler* masm = this->masm();
    __ Pop(vector, slot);
  }
  
  
  void PropertyHandlerCompiler::DiscardVectorAndSlot() {
    MacroAssembler* masm = this->masm();
    // Remove vector and slot.
    __ Addu(sp, sp, Operand(2 * kPointerSize));
  }
  
  
  void PropertyHandlerCompiler::GenerateDictionaryNegativeLookup(
      MacroAssembler* masm, Label* miss_label, Register receiver,
      Handle<Name> name, Register scratch0, Register scratch1) {
    DCHECK(name->IsUniqueName());
    DCHECK(!receiver.is(scratch0));
    Counters* counters = masm->isolate()->counters();
    __ IncrementCounter(counters->negative_lookups(), 1, scratch0, scratch1);
    __ IncrementCounter(counters->negative_lookups_miss(), 1, scratch0, scratch1);
  
    Label done;
  
    const int kInterceptorOrAccessCheckNeededMask =
    (1 << Map::kHasNamedInterceptor) | (1 << Map::kIsAccessCheckNeeded);
  
    // Bail out if the receiver has a named interceptor or requires access checks.
    Register map = scratch1;
    __ lw(map, FieldMemOperand(receiver, HeapObject::kMapOffset));
    __ lbu(scratch0, FieldMemOperand(map, Map::kBitFieldOffset));
    __ And(scratch0, scratch0, Operand(kInterceptorOrAccessCheckNeededMask));
    __ Branch(miss_label, ne, scratch0, Operand(zero_reg));
  
    // Check that receiver is a JSObject.
    __ lbu(scratch0, FieldMemOperand(map, Map::kInstanceTypeOffset));
    __ Branch(miss_label, lt, scratch0, Operand(FIRST_SPEC_OBJECT_TYPE));
  
    // Load properties array.
    Register properties = scratch0;
    __ lw(properties, FieldMemOperand(receiver, JSObject::kPropertiesOffset));
    // Check that the properties array is a dictionary.
    __ lw(map, FieldMemOperand(properties, HeapObject::kMapOffset));
    Register tmp = properties;
    __ LoadRoot(tmp, Heap::kHashTableMapRootIndex);
    __ Branch(miss_label, ne, map, Operand(tmp));
  
    // Restore the temporarily used register.
    __ lw(properties, FieldMemOperand(receiver, JSObject::kPropertiesOffset));
  
  
    NameDictionaryLookupStub::GenerateNegativeLookup(
        masm, miss_label, &done, receiver, properties, name, scratch1);
    __ bind(&done);
    __ DecrementCounter(counters->negative_lookups_miss(), 1, scratch0, scratch1);
  }
  
  
  void NamedLoadHandlerCompiler::GenerateDirectLoadGlobalFunctionPrototype(
      MacroAssembler* masm, int index, Register result, Label* miss) {
    const int offset = Context::SlotOffset(Context::GLOBAL_OBJECT_INDEX);
    __ lw(result, MemOperand(cp, offset));
    __ lw(result, FieldMemOperand(result, GlobalObject::kNativeContextOffset));
    __ lw(result, MemOperand(result, Context::SlotOffset(index)));
    // Load its initial map. The global functions all have initial maps.
    __ lw(result,
          FieldMemOperand(result, JSFunction::kPrototypeOrInitialMapOffset));
    // Load the prototype from the initial map.
    __ lw(result, FieldMemOperand(result, Map::kPrototypeOffset));
  }
  
  
  void NamedLoadHandlerCompiler::GenerateLoadFunctionPrototype(
      MacroAssembler* masm, Register receiver, Register scratch1,
      Register scratch2, Label* miss_label) {
    __ TryGetFunctionPrototype(receiver, scratch1, scratch2, miss_label);
    __ Ret(USE_DELAY_SLOT);
    __ mov(v0, scratch1);
  }
  
  
  // Generate code to check that a global property cell is empty. Create
  // the property cell at compilation time if no cell exists for the
  // property.
  void PropertyHandlerCompiler::GenerateCheckPropertyCell(
      MacroAssembler* masm, Handle<JSGlobalObject> global, Handle<Name> name,
      Register scratch, Label* miss) {
    Handle<Cell> cell = JSGlobalObject::EnsurePropertyCell(global, name);
    DCHECK(cell->value()->IsTheHole());
    Handle<WeakCell> weak_cell = masm->isolate()->factory()->NewWeakCell(cell);
    __ LoadWeakValue(scratch, weak_cell, miss);
    __ lw(scratch, FieldMemOperand(scratch, Cell::kValueOffset));
    __ LoadRoot(at, Heap::kTheHoleValueRootIndex);
    __ Branch(miss, ne, scratch, Operand(at));
  }
  
  
  static void PushInterceptorArguments(MacroAssembler* masm, Register receiver,
                                       Register holder, Register name,
                                       Handle<JSObject> holder_obj) {
    STATIC_ASSERT(NamedLoadHandlerCompiler::kInterceptorArgsNameIndex == 0);
    STATIC_ASSERT(NamedLoadHandlerCompiler::kInterceptorArgsThisIndex == 1);
    STATIC_ASSERT(NamedLoadHandlerCompiler::kInterceptorArgsHolderIndex == 2);
    STATIC_ASSERT(NamedLoadHandlerCompiler::kInterceptorArgsLength == 3);
    __ Push(name, receiver, holder);
  }
  
  
  static void CompileCallLoadPropertyWithInterceptor(
      MacroAssembler* masm, Register receiver, Register holder, Register name,
      Handle<JSObject> holder_obj, IC::UtilityId id) {
    PushInterceptorArguments(masm, receiver, holder, name, holder_obj);
    __ CallExternalReference(ExternalReference(IC_Utility(id), masm->isolate()),
                             NamedLoadHandlerCompiler::kInterceptorArgsLength);
  }
  
  
  // Generate call to api function.
  void PropertyHandlerCompiler::GenerateApiAccessorCall(
      MacroAssembler* masm, const CallOptimization& optimization,
      Handle<Map> receiver_map, Register receiver, Register scratch_in,
      bool is_store, Register store_parameter, Register accessor_holder,
      int accessor_index) {
    DCHECK(!accessor_holder.is(scratch_in));
    DCHECK(!receiver.is(scratch_in));
    __ push(receiver);
    // Write the arguments to stack frame.
    if (is_store) {
      DCHECK(!receiver.is(store_parameter));
      DCHECK(!scratch_in.is(store_parameter));
      __ push(store_parameter);
    }
    DCHECK(optimization.is_simple_api_call());
  
    // Abi for CallApiFunctionStub.
    Register callee = a0;
    Register data = t0;
    Register holder = a2;
    Register api_function_address = a1;
  
    // Put callee in place.
    __ LoadAccessor(callee, accessor_holder, accessor_index,
                    is_store ? ACCESSOR_SETTER : ACCESSOR_GETTER);
  
    // Put holder in place.
    CallOptimization::HolderLookup holder_lookup;
    int holder_depth = 0;
    optimization.LookupHolderOfExpectedType(receiver_map, &holder_lookup,
                                            &holder_depth);
    switch (holder_lookup) {
      case CallOptimization::kHolderIsReceiver:
        __ Move(holder, receiver);
        break;
      case CallOptimization::kHolderFound:
        __ lw(holder, FieldMemOperand(receiver, HeapObject::kMapOffset));
        __ lw(holder, FieldMemOperand(holder, Map::kPrototypeOffset));
        for (int i = 1; i < holder_depth; i++) {
          __ lw(holder, FieldMemOperand(holder, HeapObject::kMapOffset));
          __ lw(holder, FieldMemOperand(holder, Map::kPrototypeOffset));
        }
        break;
      case CallOptimization::kHolderNotFound:
        UNREACHABLE();
        break;
    }
  
    Isolate* isolate = masm->isolate();
    Handle<CallHandlerInfo> api_call_info = optimization.api_call_info();
    bool call_data_undefined = false;
    // Put call data in place.
    if (api_call_info->data()->IsUndefined()) {
      call_data_undefined = true;
      __ LoadRoot(data, Heap::kUndefinedValueRootIndex);
    } else {
      __ lw(data, FieldMemOperand(callee, JSFunction::kSharedFunctionInfoOffset));
      __ lw(data, FieldMemOperand(data, SharedFunctionInfo::kFunctionDataOffset));
      __ lw(data, FieldMemOperand(data, FunctionTemplateInfo::kCallCodeOffset));
      __ lw(data, FieldMemOperand(data, CallHandlerInfo::kDataOffset));
    }
    // Put api_function_address in place.
    Address function_address = v8::ToCData<Address>(api_call_info->callback());
    ApiFunction fun(function_address);
    ExternalReference::Type type = ExternalReference::DIRECT_API_CALL;
    ExternalReference ref = ExternalReference(&fun, type, masm->isolate());
    __ li(api_function_address, Operand(ref));
  
    // Jump to stub.
    CallApiAccessorStub stub(isolate, is_store, call_data_undefined);
    __ TailCallStub(&stub);
  }
  
  
  void NamedStoreHandlerCompiler::GenerateSlow(MacroAssembler* masm) {
    // Push receiver, key and value for runtime call.
    __ Push(StoreDescriptor::ReceiverRegister(), StoreDescriptor::NameRegister(),
            StoreDescriptor::ValueRegister());
  
    // The slow case calls into the runtime to complete the store without causing
    // an IC miss that would otherwise cause a transition to the generic stub.
    ExternalReference ref =
        ExternalReference(IC_Utility(IC::kStoreIC_Slow), masm->isolate());
    __ TailCallExternalReference(ref, 3, 1);
  }
  
  
  void ElementHandlerCompiler::GenerateStoreSlow(MacroAssembler* masm) {
    // Push receiver, key and value for runtime call.
    __ Push(StoreDescriptor::ReceiverRegister(), StoreDescriptor::NameRegister(),
            StoreDescriptor::ValueRegister());
  
    // The slow case calls into the runtime to complete the store without causing
    // an IC miss that would otherwise cause a transition to the generic stub.
    ExternalReference ref =
        ExternalReference(IC_Utility(IC::kKeyedStoreIC_Slow), masm->isolate());
    __ TailCallExternalReference(ref, 3, 1);
  }
  
  
  #undef __
  #define __ ACCESS_MASM(masm())
  
  
  void NamedStoreHandlerCompiler::GenerateRestoreName(Label* label,
                                                      Handle<Name> name) {
    if (!label->is_unused()) {
      __ bind(label);
      __ li(this->name(), Operand(name));
    }
  }
  
  
  void NamedStoreHandlerCompiler::GenerateRestoreName(Handle<Name> name) {
    __ li(this->name(), Operand(name));
  }
  
  
  void NamedStoreHandlerCompiler::GenerateRestoreMap(Handle<Map> transition,
                                                     Register scratch,
                                                     Label* miss) {
    Handle<WeakCell> cell = Map::WeakCellForMap(transition);
    Register map_reg = StoreTransitionDescriptor::MapRegister();
    DCHECK(!map_reg.is(scratch));
    __ LoadWeakValue(map_reg, cell, miss);
    if (transition->CanBeDeprecated()) {
      __ lw(scratch, FieldMemOperand(map_reg, Map::kBitField3Offset));
      __ And(at, scratch, Operand(Map::Deprecated::kMask));
      __ Branch(miss, ne, at, Operand(zero_reg));
    }
  }
  
  
  void NamedStoreHandlerCompiler::GenerateConstantCheck(Register map_reg,
                                                        int descriptor,
                                                        Register value_reg,
                                                        Register scratch,
                                                        Label* miss_label) {
    DCHECK(!map_reg.is(scratch));
    DCHECK(!map_reg.is(value_reg));
    DCHECK(!value_reg.is(scratch));
    __ LoadInstanceDescriptors(map_reg, scratch);
    __ lw(scratch,
          FieldMemOperand(scratch, DescriptorArray::GetValueOffset(descriptor)));
    __ Branch(miss_label, ne, value_reg, Operand(scratch));
  }
  
  
  void NamedStoreHandlerCompiler::GenerateFieldTypeChecks(HeapType* field_type,
                                                          Register value_reg,
                                                          Label* miss_label) {
    Register map_reg = scratch1();
    Register scratch = scratch2();
    DCHECK(!value_reg.is(map_reg));
    DCHECK(!value_reg.is(scratch));
    __ JumpIfSmi(value_reg, miss_label);
    HeapType::Iterator<Map> it = field_type->Classes();
    if (!it.Done()) {
      __ lw(map_reg, FieldMemOperand(value_reg, HeapObject::kMapOffset));
      Label do_store;
      while (true) {
        // Compare map directly within the Branch() functions.
        __ GetWeakValue(scratch, Map::WeakCellForMap(it.Current()));
        it.Advance();
        if (it.Done()) {
          __ Branch(miss_label, ne, map_reg, Operand(scratch));
          break;
        }
        __ Branch(&do_store, eq, map_reg, Operand(scratch));
      }
      __ bind(&do_store);
    }
  }
  
  
  Register PropertyHandlerCompiler::CheckPrototypes(
      Register object_reg, Register holder_reg, Register scratch1,
      Register scratch2, Handle<Name> name, Label* miss,
      PrototypeCheckType check) {
    Handle<Map> receiver_map = map();
  
    // Make sure there's no overlap between holder and object registers.
    DCHECK(!scratch1.is(object_reg) && !scratch1.is(holder_reg));
    DCHECK(!scratch2.is(object_reg) && !scratch2.is(holder_reg) &&
           !scratch2.is(scratch1));
  
    // Keep track of the current object in register reg.
    Register reg = object_reg;
    int depth = 0;
  
    Handle<JSObject> current = Handle<JSObject>::null();
    if (receiver_map->IsJSGlobalObjectMap()) {
      current = isolate()->global_object();
    }
    Handle<JSObject> prototype = Handle<JSObject>::null();
    Handle<Map> current_map = receiver_map;
    Handle<Map> holder_map(holder()->map());
    // Traverse the prototype chain and check the maps in the prototype chain for
    // fast and global objects or do negative lookup for normal objects.
    while (!current_map.is_identical_to(holder_map)) {
      ++depth;
  
      // Only global objects and objects that do not require access
      // checks are allowed in stubs.
      DCHECK(current_map->IsJSGlobalProxyMap() ||
             !current_map->is_access_check_needed());
  
      prototype = handle(JSObject::cast(current_map->prototype()));
      if (current_map->is_dictionary_map() &&
          !current_map->IsJSGlobalObjectMap()) {
        DCHECK(!current_map->IsJSGlobalProxyMap());  // Proxy maps are fast.
        if (!name->IsUniqueName()) {
          DCHECK(name->IsString());
          name = factory()->InternalizeString(Handle<String>::cast(name));
        }
        DCHECK(current.is_null() ||
               current->property_dictionary()->FindEntry(name) ==
                   NameDictionary::kNotFound);
  
        GenerateDictionaryNegativeLookup(masm(), miss, reg, name, scratch1,
                                         scratch2);
  
        __ lw(scratch1, FieldMemOperand(reg, HeapObject::kMapOffset));
        reg = holder_reg;  // From now on the object will be in holder_reg.
        __ lw(reg, FieldMemOperand(scratch1, Map::kPrototypeOffset));
      } else {
        Register map_reg = scratch1;
        __ lw(map_reg, FieldMemOperand(reg, HeapObject::kMapOffset));
        if (depth != 1 || check == CHECK_ALL_MAPS) {
          Handle<WeakCell> cell = Map::WeakCellForMap(current_map);
          __ GetWeakValue(scratch2, cell);
          __ Branch(miss, ne, scratch2, Operand(map_reg));
        }
  
        // Check access rights to the global object.  This has to happen after
        // the map check so that we know that the object is actually a global
        // object.
        // This allows us to install generated handlers for accesses to the
        // global proxy (as opposed to using slow ICs). See corresponding code
        // in LookupForRead().
        if (current_map->IsJSGlobalProxyMap()) {
          __ CheckAccessGlobalProxy(reg, scratch2, miss);
        } else if (current_map->IsJSGlobalObjectMap()) {
          GenerateCheckPropertyCell(masm(), Handle<JSGlobalObject>::cast(current),
                                    name, scratch2, miss);
        }
  
        reg = holder_reg;  // From now on the object will be in holder_reg.
  
        __ lw(reg, FieldMemOperand(map_reg, Map::kPrototypeOffset));
      }
  
      // Go to the next object in the prototype chain.
      current = prototype;
      current_map = handle(current->map());
    }
  
    // Log the check depth.
    LOG(isolate(), IntEvent("check-maps-depth", depth + 1));
  
    if (depth != 0 || check == CHECK_ALL_MAPS) {
      // Check the holder map.
      __ lw(scratch1, FieldMemOperand(reg, HeapObject::kMapOffset));
      Handle<WeakCell> cell = Map::WeakCellForMap(current_map);
      __ GetWeakValue(scratch2, cell);
      __ Branch(miss, ne, scratch2, Operand(scratch1));
    }
  
    // Perform security check for access to the global object.
    DCHECK(current_map->IsJSGlobalProxyMap() ||
           !current_map->is_access_check_needed());
    if (current_map->IsJSGlobalProxyMap()) {
      __ CheckAccessGlobalProxy(reg, scratch1, miss);
    }
  
    // Return the register containing the holder.
    return reg;
  }
  
  
  void NamedLoadHandlerCompiler::FrontendFooter(Handle<Name> name, Label* miss) {
    if (!miss->is_unused()) {
      Label success;
      __ Branch(&success);
      __ bind(miss);
      if (IC::ICUseVector(kind())) {
        DCHECK(kind() == Code::LOAD_IC);
        PopVectorAndSlot();
      }
      TailCallBuiltin(masm(), MissBuiltin(kind()));
      __ bind(&success);
    }
  }
  
  
  void NamedStoreHandlerCompiler::FrontendFooter(Handle<Name> name, Label* miss) {
    if (!miss->is_unused()) {
      Label success;
      __ Branch(&success);
      GenerateRestoreName(miss, name);
      TailCallBuiltin(masm(), MissBuiltin(kind()));
      __ bind(&success);
    }
  }
  
  
  void NamedLoadHandlerCompiler::GenerateLoadConstant(Handle<Object> value) {
    // Return the constant value.
    __ li(v0, value);
    __ Ret();
  }
  
  
  void NamedLoadHandlerCompiler::GenerateLoadCallback(
      Register reg, Handle<ExecutableAccessorInfo> callback) {
    // Build AccessorInfo::args_ list on the stack and push property name below
    // the exit frame to make GC aware of them and store pointers to them.
    STATIC_ASSERT(PropertyCallbackArguments::kHolderIndex == 0);
    STATIC_ASSERT(PropertyCallbackArguments::kIsolateIndex == 1);
    STATIC_ASSERT(PropertyCallbackArguments::kReturnValueDefaultValueIndex == 2);
    STATIC_ASSERT(PropertyCallbackArguments::kReturnValueOffset == 3);
    STATIC_ASSERT(PropertyCallbackArguments::kDataIndex == 4);
    STATIC_ASSERT(PropertyCallbackArguments::kThisIndex == 5);
    STATIC_ASSERT(PropertyCallbackArguments::kArgsLength == 6);
    DCHECK(!scratch2().is(reg));
    DCHECK(!scratch3().is(reg));
    DCHECK(!scratch4().is(reg));
    __ push(receiver());
    Handle<Object> data(callback->data(), isolate());
    if (data->IsUndefined() || data->IsSmi()) {
      __ li(scratch3(), data);
    } else {
      Handle<WeakCell> cell =
          isolate()->factory()->NewWeakCell(Handle<HeapObject>::cast(data));
      // The callback is alive if this instruction is executed,
      // so the weak cell is not cleared and points to data.
      __ GetWeakValue(scratch3(), cell);
    }
    __ Subu(sp, sp, 6 * kPointerSize);
    __ sw(scratch3(), MemOperand(sp, 5 * kPointerSize));
    __ LoadRoot(scratch3(), Heap::kUndefinedValueRootIndex);
    __ sw(scratch3(), MemOperand(sp, 4 * kPointerSize));
    __ sw(scratch3(), MemOperand(sp, 3 * kPointerSize));
    __ li(scratch4(), Operand(ExternalReference::isolate_address(isolate())));
    __ sw(scratch4(), MemOperand(sp, 2 * kPointerSize));
    __ sw(reg, MemOperand(sp, 1 * kPointerSize));
    __ sw(name(), MemOperand(sp, 0 * kPointerSize));
    __ Addu(scratch2(), sp, 1 * kPointerSize);
  
    __ mov(a2, scratch2());  // Saved in case scratch2 == a1.
    // Abi for CallApiGetter.
    Register getter_address_reg = ApiGetterDescriptor::function_address();
  
    Address getter_address = v8::ToCData<Address>(callback->getter());
    ApiFunction fun(getter_address);
    ExternalReference::Type type = ExternalReference::DIRECT_GETTER_CALL;
    ExternalReference ref = ExternalReference(&fun, type, isolate());
    __ li(getter_address_reg, Operand(ref));
  
    CallApiGetterStub stub(isolate());
    __ TailCallStub(&stub);
  }
  
  
  void NamedLoadHandlerCompiler::GenerateLoadInterceptorWithFollowup(
      LookupIterator* it, Register holder_reg) {
    DCHECK(holder()->HasNamedInterceptor());
    DCHECK(!holder()->GetNamedInterceptor()->getter()->IsUndefined());
  
    // Compile the interceptor call, followed by inline code to load the
    // property from further up the prototype chain if the call fails.
    // Check that the maps haven't changed.
    DCHECK(holder_reg.is(receiver()) || holder_reg.is(scratch1()));
  
    // Preserve the receiver register explicitly whenever it is different from the
    // holder and it is needed should the interceptor return without any result.
    // The ACCESSOR case needs the receiver to be passed into C++ code, the FIELD
    // case might cause a miss during the prototype check.
    bool must_perform_prototype_check =
        !holder().is_identical_to(it->GetHolder<JSObject>());
    bool must_preserve_receiver_reg =
        !receiver().is(holder_reg) &&
        (it->state() == LookupIterator::ACCESSOR || must_perform_prototype_check);
  
    // Save necessary data before invoking an interceptor.
    // Requires a frame to make GC aware of pushed pointers.
    {
      FrameScope frame_scope(masm(), StackFrame::INTERNAL);
      if (must_preserve_receiver_reg) {
        __ Push(receiver(), holder_reg, this->name());
      } else {
        __ Push(holder_reg, this->name());
      }
      InterceptorVectorSlotPush(holder_reg);
      // Invoke an interceptor.  Note: map checks from receiver to
      // interceptor's holder has been compiled before (see a caller
      // of this method).
      CompileCallLoadPropertyWithInterceptor(
          masm(), receiver(), holder_reg, this->name(), holder(),
          IC::kLoadPropertyWithInterceptorOnly);
  
      // Check if interceptor provided a value for property.  If it's
      // the case, return immediately.
      Label interceptor_failed;
      __ LoadRoot(scratch1(), Heap::kNoInterceptorResultSentinelRootIndex);
      __ Branch(&interceptor_failed, eq, v0, Operand(scratch1()));
      frame_scope.GenerateLeaveFrame();
      __ Ret();
  
      __ bind(&interceptor_failed);
      InterceptorVectorSlotPop(holder_reg);
      if (must_preserve_receiver_reg) {
        __ Pop(receiver(), holder_reg, this->name());
      } else {
        __ Pop(holder_reg, this->name());
      }
      // Leave the internal frame.
    }
  
    GenerateLoadPostInterceptor(it, holder_reg);
  }
  
  
  void NamedLoadHandlerCompiler::GenerateLoadInterceptor(Register holder_reg) {
    // Call the runtime system to load the interceptor.
    DCHECK(holder()->HasNamedInterceptor());
    DCHECK(!holder()->GetNamedInterceptor()->getter()->IsUndefined());
    PushInterceptorArguments(masm(), receiver(), holder_reg, this->name(),
                             holder());
  
    ExternalReference ref = ExternalReference(
        IC_Utility(IC::kLoadPropertyWithInterceptor), isolate());
    __ TailCallExternalReference(
        ref, NamedLoadHandlerCompiler::kInterceptorArgsLength, 1);
  }
  
  
  Handle<Code> NamedStoreHandlerCompiler::CompileStoreCallback(
      Handle<JSObject> object, Handle<Name> name,
      Handle<ExecutableAccessorInfo> callback) {
    Register holder_reg = Frontend(name);
  
    __ Push(receiver(), holder_reg);  // Receiver.
    // If the callback cannot leak, then push the callback directly,
    // otherwise wrap it in a weak cell.
    if (callback->data()->IsUndefined() || callback->data()->IsSmi()) {
      __ li(at, Operand(callback));
    } else {
      Handle<WeakCell> cell = isolate()->factory()->NewWeakCell(callback);
      __ li(at, Operand(cell));
    }
    __ push(at);
    __ li(at, Operand(name));
    __ Push(at, value());
  
    // Do tail-call to the runtime system.
    ExternalReference store_callback_property =
        ExternalReference(IC_Utility(IC::kStoreCallbackProperty), isolate());
    __ TailCallExternalReference(store_callback_property, 5, 1);
  
    // Return the generated code.
    return GetCode(kind(), Code::FAST, name);
  }
  
  
  Handle<Code> NamedStoreHandlerCompiler::CompileStoreInterceptor(
      Handle<Name> name) {
    __ Push(receiver(), this->name(), value());
  
    // Do tail-call to the runtime system.
    ExternalReference store_ic_property = ExternalReference(
        IC_Utility(IC::kStorePropertyWithInterceptor), isolate());
    __ TailCallExternalReference(store_ic_property, 3, 1);
  
    // Return the generated code.
    return GetCode(kind(), Code::FAST, name);
  }
  
  
  Register NamedStoreHandlerCompiler::value() {
    return StoreDescriptor::ValueRegister();
  }
  
  
  Handle<Code> NamedLoadHandlerCompiler::CompileLoadGlobal(
      Handle<PropertyCell> cell, Handle<Name> name, bool is_configurable) {
    Label miss;
    if (IC::ICUseVector(kind())) {
      PushVectorAndSlot();
    }
  
    FrontendHeader(receiver(), name, &miss);
  
    // Get the value from the cell.
    Register result = StoreDescriptor::ValueRegister();
    Handle<WeakCell> weak_cell = factory()->NewWeakCell(cell);
    __ LoadWeakValue(result, weak_cell, &miss);
    __ lw(result, FieldMemOperand(result, Cell::kValueOffset));
  
    // Check for deleted property if property can actually be deleted.
    if (is_configurable) {
      __ LoadRoot(at, Heap::kTheHoleValueRootIndex);
      __ Branch(&miss, eq, result, Operand(at));
    }
  
    Counters* counters = isolate()->counters();
    __ IncrementCounter(counters->named_load_global_stub(), 1, a1, a3);
    if (IC::ICUseVector(kind())) {
      DiscardVectorAndSlot();
    }
    __ Ret(USE_DELAY_SLOT);
    __ mov(v0, result);
  
    FrontendFooter(name, &miss);
  
    // Return the generated code.
    return GetCode(kind(), Code::NORMAL, name);
  }
  
  
  #undef __
  }
  }  // namespace v8::internal
  
  #endif  // V8_TARGET_ARCH_MIPS
  