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/*
* 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.
*/
#include "cpu_features_wrapper.h"
// No CPU feature is available => straight C path.
int GetCPUInfoNoASM(CPUFeature feature) {
(void)feature;
return 0;
}
// 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));
}
#elif defined(__i386__) || defined(__x86_64__)
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
#if defined(__i386__) || defined(__x86_64__)
// 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;
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