Revert r4782. Fix issues 728, 732.

src/ia32/ic-ia32.cc

 // Copyright 2010 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 386 matching lines @@
 
   __ bind(&check_string);
   // The key is not a smi.
   // Is it a string?
   // edx: receiver
   // eax: key
   __ CmpObjectType(eax, FIRST_NONSTRING_TYPE, ecx);
   __ j(above_equal, &slow);
   // Is the string an array index, with cached numeric value?
   __ mov(ebx, FieldOperand(eax, String::kHashFieldOffset));
-  __ test(ebx, Immediate(String::kIsArrayIndexMask));
-  __ j(not_zero, &index_string, not_taken);
+  __ test(ebx, Immediate(String::kContainsCachedArrayIndexMask));
+  __ j(zero, &index_string, not_taken);
 
   // Is the string a symbol?
   // ecx: key map.
   ASSERT(kSymbolTag != 0);
   __ test_b(FieldOperand(ecx, Map::kInstanceTypeOffset), kIsSymbolMask);
   __ j(zero, &slow, not_taken);
 
   // If the receiver is a fast-case object, check the keyed lookup
   // cache. Otherwise probe the dictionary.
   __ mov(ebx, FieldOperand(edx, JSObject::kPropertiesOffset));
@@ skipping 1196 matching lines @@
   ExternalReference ref = ExternalReference(IC_Utility(kKeyedStoreIC_Miss));
   __ TailCallExternalReference(ref, 3, 1);
 }
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32