From b015cbede88899f67a53fbbe581b02ce8e327949 Mon Sep 17 00:00:00 2001 From: "andrew@webrtc.org" Date: Mon, 22 Oct 2012 18:19:23 +0000 Subject: Move src/ -> webrtc/ TBR=niklas.enbom@webrtc.org Review URL: https://webrtc-codereview.appspot.com/915006 git-svn-id: http://webrtc.googlecode.com/svn/trunk/webrtc@2963 4adac7df-926f-26a2-2b94-8c16560cd09d --- system_wrappers/source/cpu_features.cc | 74 ++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) create mode 100644 system_wrappers/source/cpu_features.cc (limited to 'system_wrappers/source/cpu_features.cc') diff --git a/system_wrappers/source/cpu_features.cc b/system_wrappers/source/cpu_features.cc new file mode 100644 index 00000000..41a86e36 --- /dev/null +++ b/system_wrappers/source/cpu_features.cc @@ -0,0 +1,74 @@ +/* + * 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 "cpu_features_wrapper.h" + +#include "typedefs.h" + +#if defined(WEBRTC_ARCH_X86_FAMILY) +#if defined(_MSC_VER) +#include +#endif +#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; -- cgit v1.2.3