Always require exact maps.

src/ia32/macro-assembler-ia32.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 562 matching lines @@
     pop(scratch1);
     fstp_d(FieldOperand(elements, key, times_4,
                         FixedDoubleArray::kHeaderSize - elements_offset));
   }
   bind(&done);
 }
 
 
 void MacroAssembler::CompareMap(Register obj,
                                 Handle<Map> map,
-                                Label* early_success,
-                                CompareMapMode mode) {
+                                Label* early_success) {
   cmp(FieldOperand(obj, HeapObject::kMapOffset), map);
-  if (mode == ALLOW_ELEMENT_TRANSITION_MAPS) {
-    ElementsKind kind = map->elements_kind();
-    if (IsFastElementsKind(kind)) {
-      bool packed = IsFastPackedElementsKind(kind);
-      Map* current_map = *map;
-      while (CanTransitionToMoreGeneralFastElementsKind(kind, packed)) {
-        kind = GetNextMoreGeneralFastElementsKind(kind, packed);
-        current_map = current_map->LookupElementsTransitionMap(kind);
-        if (!current_map) break;
-        j(equal, early_success, Label::kNear);
-        cmp(FieldOperand(obj, HeapObject::kMapOffset),
-            Handle<Map>(current_map));
-      }
-    }
-  }
 }
 
 
 void MacroAssembler::CheckMap(Register obj,
                               Handle<Map> map,
                               Label* fail,
-                              SmiCheckType smi_check_type,
-                              CompareMapMode mode) {
+                              SmiCheckType smi_check_type) {
   if (smi_check_type == DO_SMI_CHECK) {
     JumpIfSmi(obj, fail);
   }
 
   Label success;
-  CompareMap(obj, map, &success, mode);
+  CompareMap(obj, map, &success);
   j(not_equal, fail);
   bind(&success);
 }
 
 
 void MacroAssembler::DispatchMap(Register obj,
                                  Register unused,
                                  Handle<Map> map,
                                  Handle<Code> success,
                                  SmiCheckType smi_check_type) {
@@ skipping 2490 matching lines @@
   j(greater, &no_info_available);
   cmp(MemOperand(scratch_reg, -AllocationSiteInfo::kSize),
       Immediate(Handle<Map>(isolate()->heap()->allocation_site_info_map())));
   bind(&no_info_available);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32