Tag previously GENERIC stubs that potentially IC_Miss as MONOMORPHIC.

src/ic.cc

Index: src/ic.cc
diff --git a/src/ic.cc b/src/ic.cc
index c452791e7525ef682ef28ed78f18f80e16ca7b60..3024f681e35cd437fec2c2dc37f61679d5e3c98a 100644
--- a/src/ic.cc
+++ b/src/ic.cc
@@ -1004,9 +1004,11 @@ void IC::PatchCache(State state,
                  ? *generic_stub_strict()
                  : *generic_stub());
       break;
-    case GENERIC:
     case DEBUG_STUB:
       break;
+    case GENERIC:
+      UNREACHABLE();
+      break;
   }
 }
 
@@ -1169,11 +1171,11 @@ static void GetReceiverMapsForStub(Handle<Code> stub,
       break;
     }
     case MEGAMORPHIC:
-    case GENERIC:
       break;
     case UNINITIALIZED:
     case PREMONOMORPHIC:
     case MONOMORPHIC_PROTOTYPE_FAILURE:
+    case GENERIC:
     case DEBUG_STUB:
       UNREACHABLE();
       break;
@@ -1223,7 +1225,7 @@ Handle<Code> KeyedLoadIC::LoadElementStub(Handle<JSObject> receiver) {
     return isolate()->stub_cache()->ComputeKeyedLoadElement(receiver_map);
   }
 
-  ASSERT(target() != *generic_stub());
+  ASSERT(ic_state != GENERIC);
 
   // Determine the list of receiver maps that this call site has seen,
   // adding the map that was just encountered.
@@ -1605,7 +1607,7 @@ Handle<Code> KeyedStoreIC::StoreElementStub(Handle<JSObject> receiver,
         monomorphic_map, stub_kind, strict_mode, grow_mode);
   }
 
-  ASSERT(target() != *generic_stub() && target() != *generic_stub_strict());
+  ASSERT(ic_state != GENERIC);
 
   bool map_added =
       AddOneReceiverMapIfMissing(&target_receiver_maps, receiver_map);