Allow a platform to indicate that some CPU features are always...

src/platform-win32.cc

 // Copyright 2006-2008 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 1298 matching lines @@
 
 // Restore warnings to previous settings.
 #pragma warning(pop)
 
 #else  // __MINGW32__
 void OS::LogSharedLibraryAddresses() { }
 int OS::StackWalk(Vector<OS::StackFrame> frames) { return 0; }
 #endif  // __MINGW32__
 
 
+uint64_t OS::CpuFeaturesImpliedByPlatform() {
+  return 0;  // Windows runs on anything.
+}
+
+
 double OS::nan_value() {
 #ifdef _MSC_VER
   // Positive Quiet NaN with no payload (aka. Indeterminate) has all bits
   // in mask set, so value equals mask.
   static const __int64 nanval = kQuietNaNMask;
   return *reinterpret_cast<const double*>(&nanval);
 #else  // _MSC_VER
   return NAN;
 #endif  // _MSC_VER
 }
@@ skipping 565 matching lines @@
 
   // Release the thread handles
   CloseHandle(data_->sampler_thread_);
   CloseHandle(data_->profiled_thread_);
 }
 
 
 #endif  // ENABLE_LOGGING_AND_PROFILING
 
 } }  // namespace v8::internal