Revert "Make new space iterable when transitioning double array to objects"

src/x64/codegen-x64.cc

Index: src/x64/codegen-x64.cc
diff --git a/src/x64/codegen-x64.cc b/src/x64/codegen-x64.cc
index 3393982606580fa31c55125c830a8f4893ea633d..afcf58171b49ee4010a756707668f703000969e1 100644
--- a/src/x64/codegen-x64.cc
+++ b/src/x64/codegen-x64.cc
@@ -369,7 +369,7 @@ void ElementsTransitionGenerator::GenerateDoubleToObject(
   //  -- rdx    : receiver
   //  -- rsp[0] : return address
   // -----------------------------------
-  Label loop, entry, convert_hole, gc_required, gc_cleanup, only_change_map;
+  Label loop, entry, convert_hole, gc_required, only_change_map;
 
   if (mode == TRACK_ALLOCATION_SITE) {
     __ JumpIfJSArrayHasAllocationMemento(rdx, rdi, fail);
@@ -402,19 +402,6 @@ void ElementsTransitionGenerator::GenerateDoubleToObject(
   // rdi: pointer to the-hole
   __ jmp(&entry);
 
-  __ bind(&gc_cleanup);
-#ifdef VERIFY_HEAP
-  // Make sure new space is iterable if we are verifying the heap.
-  __ Move(rax, masm->isolate()->factory()->one_pointer_filler_map());
-  __ movp(FieldOperand(r11,
-                       r9,
-                       times_pointer_size,
-                       FixedArray::kHeaderSize),
-          rax);
-  __ decp(r9);
-  __ j(not_sign, &gc_cleanup);
-#endif
-
   // Call into runtime if GC is required.
   __ bind(&gc_required);
   __ Pop(rax);
@@ -433,7 +420,7 @@ void ElementsTransitionGenerator::GenerateDoubleToObject(
   __ j(equal, &convert_hole);
 
   // Non-hole double, copy value into a heap number.
-  __ AllocateHeapNumber(rax, r15, &gc_cleanup);
+  __ AllocateHeapNumber(rax, r15, &gc_required);
   // rax: new heap number
   __ movq(FieldOperand(rax, HeapNumber::kValueOffset), r14);
   __ movp(FieldOperand(r11,