Use a dictionary-mode code cache on the map rather than a dual system.

src/ic/arm64/stub-cache-arm64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/codegen.h"
 #include "src/ic/ic.h"
 #include "src/ic/stub-cache.h"
 #include "src/interface-descriptors.h"
@@ skipping 77 matching lines @@
 }
 
 
 void StubCache::GenerateProbe(MacroAssembler* masm, Code::Kind ic_kind,
                               Code::Flags flags, Register receiver,
                               Register name, Register scratch, Register extra,
                               Register extra2, Register extra3) {
   Isolate* isolate = masm->isolate();
   Label miss;
 
-  // Make sure the flags does not name a specific type.
-  DCHECK(Code::ExtractTypeFromFlags(flags) == 0);
-
   // Make sure that there are no register conflicts.
   DCHECK(!AreAliased(receiver, name, scratch, extra, extra2, extra3));
 
   // Make sure extra and extra2 registers are valid.
   DCHECK(!extra.is(no_reg));
   DCHECK(!extra2.is(no_reg));
   DCHECK(!extra3.is(no_reg));
 
 #ifdef DEBUG
   // If vector-based ics are in use, ensure that scratch, extra, extra2 and
@@ skipping 44 matching lines @@
   // Cache miss: Fall-through and let caller handle the miss by
   // entering the runtime system.
   __ Bind(&miss);
   __ IncrementCounter(counters->megamorphic_stub_cache_misses(), 1, extra2,
                       extra3);
 }
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_ARM64