Use the property load IC for accessing the array length.

src/ia32/lithium-codegen-ia32.cc

Index: src/ia32/lithium-codegen-ia32.cc
diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index 6e86d920a26fcea1546ddf6e6a56254b7b59d4e1..d3f97cfb4c177585eee624d02bb1bb1202982377 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -4741,11 +4741,11 @@ void LCodeGen::DoCheckMaps(LCheckMaps* instr) {
   SmallMapList* map_set = instr->hydrogen()->map_set();
   for (int i = 0; i < map_set->length() - 1; i++) {
     Handle<Map> map = map_set->at(i);
-    __ CompareMap(reg, map, &success, REQUIRE_EXACT_MAP);
+    __ CompareMap(reg, map, &success, instr->hydrogen()->mode());
     __ j(equal, &success);
   }
   Handle<Map> map = map_set->last();
-  DoCheckMapCommon(reg, map, REQUIRE_EXACT_MAP, instr->environment());
+  DoCheckMapCommon(reg, map, instr->hydrogen()->mode(), instr->environment());
   __ bind(&success);
 }