[turbofan] Finish support for holey double elements backing stores.

src/compiler/simplified-lowering.cc

 // 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/compiler/simplified-lowering.h"
 
 #include <limits>
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
@@ skipping 758 matching lines @@
           // TODO(turbofan): avoid a truncation with a smi check.
           VisitUnop(node, kTypeUint32 | kRepFloat64, kTypeUint32 | kRepWord32);
           if (lower()) {
             NodeProperties::ChangeOp(
                 node, lowering->machine()->TruncateFloat64ToInt32(
                           TruncationMode::kJavaScript));
           }
         }
         break;
       }
+      case IrOpcode::kNumberIsHoleNaN: {
+        VisitUnop(node, kMachFloat64, kMachBool);
+        if (lower()) {
+          // NumberIsHoleNaN(x) => Word32Equal(Float64ExtractLowWord32(x),
+          //                                   #HoleNaNLower32)
+          node->ReplaceInput(0,
+                             jsgraph_->graph()->NewNode(
+                                 lowering->machine()->Float64ExtractLowWord32(),
+                                 node->InputAt(0)));
+          node->AppendInput(jsgraph_->zone(),
+                            jsgraph_->Int32Constant(kHoleNanLower32));
+          NodeProperties::ChangeOp(node, jsgraph_->machine()->Word32Equal());
+        }
+        break;
+      }
       case IrOpcode::kPlainPrimitiveToNumber: {
         VisitUnop(node, kMachAnyTagged, kTypeNumber | kRepTagged);
         if (lower()) {
           // PlainPrimitiveToNumber(x) => Call(ToNumberStub, x, no-context)
           Operator::Properties properties = node->op()->properties();
           Callable callable = CodeFactory::ToNumber(jsgraph_->isolate());
           CallDescriptor::Flags flags = CallDescriptor::kNoFlags;
           CallDescriptor* desc = Linkage::GetStubCallDescriptor(
               jsgraph_->isolate(), jsgraph_->zone(), callable.descriptor(), 0,
               flags, properties);
@@ skipping 765 matching lines @@
   ReplaceEffectUses(node, comparison);
   node->ReplaceInput(0, comparison);
   node->ReplaceInput(1, jsgraph()->SmiConstant(EQUAL));
   node->TrimInputCount(2);
   NodeProperties::ChangeOp(node, machine()->IntLessThanOrEqual());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8