Revert "Add a premonomorphic state to the call target cache."

src/arm/code-stubs-arm.cc

Index: src/arm/code-stubs-arm.cc
diff --git a/src/arm/code-stubs-arm.cc b/src/arm/code-stubs-arm.cc
index 9c03a08b9984674221d8e39513cf05c9cd942daa..c9b479eaa19e71678dc4cab049d7772269323b77 100644
--- a/src/arm/code-stubs-arm.cc
+++ b/src/arm/code-stubs-arm.cc
@@ -3017,8 +3017,6 @@ static void GenerateRecordCallTarget(MacroAssembler* masm) {
             masm->isolate()->heap()->undefined_value());
   ASSERT_EQ(*TypeFeedbackInfo::UninitializedSentinel(masm->isolate()),
             masm->isolate()->heap()->the_hole_value());
-  ASSERT_EQ(*TypeFeedbackInfo::PremonomorphicSentinel(masm->isolate()),
-            masm->isolate()->heap()->null_value());
 
   // Load the cache state into r4.
   __ add(r4, r2, Operand::PointerOffsetFromSmiKey(r3));
@@ -3045,26 +3043,10 @@ static void GenerateRecordCallTarget(MacroAssembler* masm) {
 
   __ bind(&miss);
 
-  // A monomorphic miss (i.e, here the cache is not uninitialized or
-  // pre-monomorphic) goes megamorphic.
-  Label not_uninitialized;
+  // A monomorphic miss (i.e, here the cache is not uninitialized) goes
+  // megamorphic.
   __ CompareRoot(r4, Heap::kTheHoleValueRootIndex);
-  __ b(ne, &not_uninitialized);
-
-  // PremonomorphicSentinel is an immortal immovable object (null) so no
-  // write-barrier is needed.
-  __ add(r4, r2, Operand::PointerOffsetFromSmiKey(r3));
-  __ LoadRoot(ip, Heap::kNullValueRootIndex);
-  __ str(ip, FieldMemOperand(r4, FixedArray::kHeaderSize));
-  __ jmp(&done);
-
-  // 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);
-  __ CompareRoot(r4, Heap::kNullValueRootIndex);
   __ b(eq, &initialize);
-
   // MegamorphicSentinel is an immortal immovable object (undefined) so no
   // write-barrier is needed.
   __ bind(&megamorphic);