detect cpu feature for all x64 and x86 platforms (no longer windows only).

base/cpu.h

 // Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_CPU_H_
 #define BASE_CPU_H_
 #pragma once
 
+#include "build/build_config.h"
+
 #include <string>
 
 namespace base {
 
 // Query information about the processor.
 class CPU {
  public:
   // Constructor
   CPU();
 
   // Accessors for CPU information.
   const std::string& vendor_name() const { return cpu_vendor_; }
   int stepping() const { return stepping_; }
   int model() const { return model_; }
   int family() const { return family_; }
   int type() const { return type_; }
   int extended_model() const { return ext_model_; }
   int extended_family() const { return ext_family_; }
+  int has_sse2() const { return has_sse2_; }
 
  private:
   // Query the processor for CPUID information.
   void Initialize();
 
   int type_;  // process type
   int family_;  // family of the processor
   int model_;  // model of processor
   int stepping_;  // processor revision number
   int ext_model_;
   int ext_family_;
+  bool has_sse2_;
   std::string cpu_vendor_;
 };
 
 }  // namespace base
 
 #endif  // BASE_CPU_H_