text: /*
   *  Copyright (c) 2011 The WebRTC 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 in the root of the source
   *  tree. An additional intellectual property rights grant can be found
   *  in the file PATENTS.  All contributing project authors may
   *  be found in the AUTHORS file in the root of the source tree.
   */
  
  // Parts of this file derived from Chromium's base/cpu.cc.
  
  #include "rtc_base/system/arch.h"
  #include "system_wrappers/include/cpu_features_wrapper.h"
  
  #if defined(WEBRTC_ARCH_X86_FAMILY) && defined(_MSC_VER)
  #include <intrin.h>
  #endif
  
  
  // No CPU feature is available => straight C path.
  int GetCPUInfoNoASM(CPUFeature feature) {
    (void)feature;
    return 0;
  }
  
  #if defined(WEBRTC_ARCH_X86_FAMILY)
  #ifndef _MSC_VER
  // Intrinsic for "cpuid".
  #if defined(__pic__) && defined(__i386__)
  static inline void __cpuid(int cpu_info[4], int info_type) {
    __asm__ volatile(
        "mov %%ebx, %%edi\n"
        "cpuid\n"
        "xchg %%edi, %%ebx\n"
        : "=a"(cpu_info[0]), "=D"(cpu_info[1]), "=c"(cpu_info[2]),
          "=d"(cpu_info[3])
        : "a"(info_type));
  }
  #else
  static inline void __cpuid(int cpu_info[4], int info_type) {
    __asm__ volatile("cpuid\n"
                     : "=a"(cpu_info[0]), "=b"(cpu_info[1]), "=c"(cpu_info[2]),
                       "=d"(cpu_info[3])
                     : "a"(info_type));
  }
  #endif
  #endif  // _MSC_VER
  #endif  // WEBRTC_ARCH_X86_FAMILY
  
  #if defined(WEBRTC_ARCH_X86_FAMILY)
  // Actual feature detection for x86.
  static int GetCPUInfo(CPUFeature feature) {
    int cpu_info[4];
    __cpuid(cpu_info, 1);
    if (feature == kSSE2) {
      return 0 != (cpu_info[3] & 0x04000000);
    }
    if (feature == kSSE3) {
      return 0 != (cpu_info[2] & 0x00000001);
    }
    return 0;
  }
  #else
  // Default to straight C for other platforms.
  static int GetCPUInfo(CPUFeature feature) {
    (void)feature;
    return 0;
  }
  #endif
  
  WebRtc_CPUInfo WebRtc_GetCPUInfo = GetCPUInfo;
  WebRtc_CPUInfo WebRtc_GetCPUInfoNoASM = GetCPUInfoNoASM;
  