[runtime] Avoid @@isConcatSpreadable lookup for fast path Array.prototype.concat

src/crankshaft/x87/lithium-codegen-x87.cc

 // Copyright 2012 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.
 
 #if V8_TARGET_ARCH_X87
 
 #include "src/crankshaft/x87/lithium-codegen-x87.h"
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
@@ skipping 2980 matching lines @@
       __ cmp(result, factory()->the_hole_value());
       DeoptimizeIf(equal, instr, Deoptimizer::kHole);
     }
   } else if (instr->hydrogen()->hole_mode() == CONVERT_HOLE_TO_UNDEFINED) {
     DCHECK(instr->hydrogen()->elements_kind() == FAST_HOLEY_ELEMENTS);
     Label done;
     __ cmp(result, factory()->the_hole_value());
     __ j(not_equal, &done);
     if (info()->IsStub()) {
       // A stub can safely convert the hole to undefined only if the array
-      // protector cell contains (Smi) Isolate::kArrayProtectorValid. Otherwise
-      // it needs to bail out.
-      __ mov(result, isolate()->factory()->array_protector());
+      // protector cell contains (Smi) Isolate::kArrayProtectorValid.
+      // Otherwise it needs to bail out.
+      __ LoadRoot(result, Heap::kArrayProtectorRootIndex);
       __ cmp(FieldOperand(result, PropertyCell::kValueOffset),
              Immediate(Smi::FromInt(Isolate::kArrayProtectorValid)));
       DeoptimizeIf(not_equal, instr, Deoptimizer::kHole);
     }
     __ mov(result, isolate()->factory()->undefined_value());
     __ bind(&done);
   }
 }
 
 
@@ skipping 2813 matching lines @@
   __ mov(Operand(ebp, StandardFrameConstants::kContextOffset), context);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87