Add a premonomorphic state to the call target cache.

src/ia32/code-stubs-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 2344 matching lines @@
   // Load the global or builtins object from the current context
   __ LoadGlobalContext(ecx);
   // Make sure the function is the Array() function
   __ cmp(edi, Operand(ecx,
                       Context::SlotOffset(Context::ARRAY_FUNCTION_INDEX)));
   __ j(not_equal, &megamorphic);
   __ jmp(&done, Label::kFar);
 
   __ bind(&miss);
 
-  // A monomorphic miss (i.e, here the cache is not uninitialized) goes
-  // megamorphic.
+  // A monomorphic miss (i.e, here the cache is not uninitialized or
+  // pre-monomorphic) goes megamorphic.
+  Label not_uninitialized;
   __ cmp(ecx, Immediate(TypeFeedbackInfo::UninitializedSentinel(isolate)));
+  __ j(not_equal, &not_uninitialized);
+
+  // PremonomorphicSentinel is an immortal immovable object (null) so no
+  // write-barrier is needed.
+  __ mov(FieldOperand(ebx, edx, times_half_pointer_size,
+                      FixedArray::kHeaderSize),
+         Immediate(TypeFeedbackInfo::PremonomorphicSentinel(isolate)));
+  __ jmp(&done, Label::kFar);
+
+  // If the cache isn't uninitialized, it is either premonomorphic or
+  // monomorphic. If it is premonomorphic, we initialize it thus making
+  // it monomorphic. Otherwise, we go megamorphic.
+  __ bind(&not_uninitialized);
+  __ cmp(ecx, Immediate(TypeFeedbackInfo::PremonomorphicSentinel(isolate)));
   __ j(equal, &initialize);
+
   // MegamorphicSentinel is an immortal immovable object (undefined) so no
   // write-barrier is needed.
   __ bind(&megamorphic);
   __ mov(FieldOperand(ebx, edx, times_half_pointer_size,
                       FixedArray::kHeaderSize),
          Immediate(TypeFeedbackInfo::MegamorphicSentinel(isolate)));
   __ jmp(&done, Label::kFar);
 
   // An uninitialized cache is patched with the function or sentinel to
   // indicate the ElementsKind if function is the Array constructor.
@@ skipping 3074 matching lines @@
                               Operand(ebp, 7 * kPointerSize),
                               NULL);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32