Always require exact maps.

src/x64/macro-assembler-x64.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 2820 matching lines @@
   cvtlsi2sd(xmm_scratch, kScratchRegister);
   movsd(FieldOperand(elements, index, times_8,
                      FixedDoubleArray::kHeaderSize - elements_offset),
         xmm_scratch);
   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::ClampUint8(Register reg) {
   Label done;
   testl(reg, Immediate(0xFFFFFF00));
   j(zero, &done, Label::kNear);
   setcc(negative, reg);  // 1 if negative, 0 if positive.
@@ skipping 1748 matching lines @@
   j(greater, &no_info_available);
   CompareRoot(MemOperand(scratch_reg, -AllocationSiteInfo::kSize),
               Heap::kAllocationSiteInfoMapRootIndex);
   bind(&no_info_available);
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64