Use POLYMORPHIC for polymorphic Keyed(Load|Store)IC

src/x64/stub-cache-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 2754 matching lines @@
       __ jmp(handler_stubs->at(i), RelocInfo::CODE_TARGET);
       __ bind(&next_map);
     }
   }
 
   __ bind(&miss);
   Handle<Code> ic = isolate()->builtins()->KeyedStoreIC_Miss();
   __ jmp(ic, RelocInfo::CODE_TARGET);
 
   // Return the generated code.
-  return GetCode(Code::NORMAL, factory()->empty_string(), MEGAMORPHIC);
+  return GetCode(Code::NORMAL, factory()->empty_string(), POLYMORPHIC);
 }
 
 
 Handle<Code> LoadStubCompiler::CompileLoadNonexistent(Handle<String> name,
                                                       Handle<JSObject> object,
                                                       Handle<JSObject> last) {
   // ----------- S t a t e -------------
   //  -- rax    : receiver
   //  -- rcx    : name
   //  -- rsp[0] : return address
@@ skipping 460 matching lines @@
   for (int current = 0; current < receiver_count; ++current) {
     // Check map and tail call if there's a match
     __ Cmp(map_reg, receiver_maps->at(current));
     __ j(equal, handler_ics->at(current), RelocInfo::CODE_TARGET);
   }
 
   __  bind(&miss);
   GenerateLoadMiss(masm(), Code::KEYED_LOAD_IC);
 
   // Return the generated code.
-  return GetCode(Code::NORMAL, factory()->empty_string(), MEGAMORPHIC);
+  return GetCode(Code::NORMAL, factory()->empty_string(), POLYMORPHIC);
 }
 
 
 // Specialized stub for constructing objects from functions which only have only
 // simple assignments of the form this.x = ...; in their body.
 Handle<Code> ConstructStubCompiler::CompileConstructStub(
     Handle<JSFunction> function) {
   // ----------- S t a t e -------------
   //  -- rax : argc
   //  -- rdi : constructor
@@ skipping 661 matching lines @@
     __ jmp(ic_slow, RelocInfo::CODE_TARGET);
   }
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64