X87: EmitCreateIteratorResult loads map from function's context

port r24987

original commit message:

  EmitCreateIteratorResult loads map from function's context

  Caching or serialization can cause full-codegen output to be shared
  between contexts. CreateIteratorResult, however, was doing the wrong
  thing by creating results with the map that was current when the code
  was generated. Instead, we should chase pointers to load the right map
  from the function's context.

BUG=
R=weiliang.lin@intel.com

Review URL: https://codereview.chromium.org/674073004

Patch from Chunyang Dai <chunyang.dai@intel.com>.

Cr-Commit-Position: refs/heads/master@{#25000}
git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@25000 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/x87/full-codegen-x87.cc

@@ -2232,22 +2232,25 @@ void FullCodeGenerator::EmitCreateIteratorResult(bool done) {
   Label gc_required;
   Label allocated;
 
-  Handle<Map> map(isolate()->native_context()->iterator_result_map());
+  const int instance_size = 5 * kPointerSize;
+  DCHECK_EQ(isolate()->native_context()->iterator_result_map()->instance_size(),
+            instance_size);
 
-  __ Allocate(map->instance_size(), eax, ecx, edx, &gc_required, TAG_OBJECT);
+  __ Allocate(instance_size, eax, ecx, edx, &gc_required, TAG_OBJECT);
   __ jmp(&allocated);
 
   __ bind(&gc_required);
-  __ Push(Smi::FromInt(map->instance_size()));
+  __ Push(Smi::FromInt(instance_size));
   __ CallRuntime(Runtime::kAllocateInNewSpace, 1);
   __ mov(context_register(),
          Operand(ebp, StandardFrameConstants::kContextOffset));
 
   __ bind(&allocated);
-  __ mov(ebx, map);
+  __ mov(ebx, Operand(esi, Context::SlotOffset(Context::GLOBAL_OBJECT_INDEX)));
+  __ mov(ebx, FieldOperand(ebx, GlobalObject::kNativeContextOffset));
+  __ mov(ebx, ContextOperand(ebx, Context::ITERATOR_RESULT_MAP_INDEX));
   __ pop(ecx);
   __ mov(edx, isolate()->factory()->ToBoolean(done));
-  DCHECK_EQ(map->instance_size(), 5 * kPointerSize);
   __ mov(FieldOperand(eax, HeapObject::kMapOffset), ebx);
   __ mov(FieldOperand(eax, JSObject::kPropertiesOffset),
          isolate()->factory()->empty_fixed_array());