Simplified CPU/CpuFeatures a bit.

src/arm64/cpu-arm64.h

 // Copyright 2013 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 24 matching lines @@
 namespace v8 {
 namespace internal {
 
 
 // CpuFeatures keeps track of which features are supported by the target CPU.
 // Supported features must be enabled by a CpuFeatureScope before use.
 class CpuFeatures : public AllStatic {
  public:
   // Detect features of the target CPU. Set safe defaults if the serializer
   // is enabled (snapshots must be portable).
-  static void Probe();
+  static void Probe(bool serializer_enabled);
 
   // Check whether a feature is supported by the target CPU.
   static bool IsSupported(CpuFeature f) {
     ASSERT(initialized_);
     // There are no optional features for ARM64.
     return false;
   };
 
   static bool IsFoundByRuntimeProbingOnly(CpuFeature f) {
     ASSERT(initialized_);
@@ skipping 18 matching lines @@
     return true;
   }
 
   static bool VerifyCrossCompiling(CpuFeature f) {
     // There are no optional features for ARM64.
     USE(f);
     ASSERT(cross_compile_ == 0);
     return true;
   }
 
+  static bool SupportsCrankshaft() { return true; }
+
  private:
   // Return the content of the cache type register.
   static uint32_t GetCacheType();
 
   // I and D cache line size in bytes.
   static unsigned icache_line_size_;
   static unsigned dcache_line_size_;
 
 #ifdef DEBUG
   static bool initialized_;
 #endif
 
   // This isn't used (and is always 0), but it is required by V8.
   static unsigned found_by_runtime_probing_only_;
 
   static unsigned cross_compile_;
 
   friend class PlatformFeatureScope;
   DISALLOW_COPY_AND_ASSIGN(CpuFeatures);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_ARM64_CPU_ARM64_H_