98 lines
2.4 KiB
C++
98 lines
2.4 KiB
C++
|
/*
|
||
|
|
* Copyright (c) 2016 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 <features.h>
|
||
|
|
#include <stdlib.h>
|
||
|
|
#include <string.h>
|
||
|
|
|
||
|
|
#ifdef __GLIBC_PREREQ
|
||
|
|
#define WEBRTC_GLIBC_PREREQ(a, b) __GLIBC_PREREQ(a, b)
|
||
|
|
#else
|
||
|
|
#define WEBRTC_GLIBC_PREREQ(a, b) 0
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#if WEBRTC_GLIBC_PREREQ(2, 16)
|
||
|
|
#include <sys/auxv.h>
|
||
|
|
#else
|
||
|
|
#include <errno.h>
|
||
|
|
#include <fcntl.h>
|
||
|
|
#include <link.h>
|
||
|
|
#include <unistd.h>
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#include "rtc_base/system/arch.h"
|
||
|
|
#include "system_wrappers/include/cpu_features_wrapper.h"
|
||
|
|
|
||
|
|
#if defined(WEBRTC_ARCH_ARM_FAMILY)
|
||
|
|
#include <asm/hwcap.h>
|
||
|
|
|
||
|
|
namespace webrtc {
|
||
|
|
|
||
|
|
uint64_t GetCPUFeaturesARM(void) {
|
||
|
|
uint64_t result = 0;
|
||
|
|
int architecture = 0;
|
||
|
|
uint64_t hwcap = 0;
|
||
|
|
const char* platform = NULL;
|
||
|
|
#if WEBRTC_GLIBC_PREREQ(2, 16)
|
||
|
|
hwcap = getauxval(AT_HWCAP);
|
||
|
|
platform = (const char*)getauxval(AT_PLATFORM);
|
||
|
|
#else
|
||
|
|
ElfW(auxv_t) auxv;
|
||
|
|
int fd = open("/proc/self/auxv", O_RDONLY);
|
||
|
|
if (fd >= 0) {
|
||
|
|
while (hwcap == 0 || platform == NULL) {
|
||
|
|
if (read(fd, &auxv, sizeof(auxv)) < (ssize_t)sizeof(auxv)) {
|
||
|
|
if (errno == EINTR)
|
||
|
|
continue;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
switch (auxv.a_type) {
|
||
|
|
case AT_HWCAP:
|
||
|
|
hwcap = auxv.a_un.a_val;
|
||
|
|
break;
|
||
|
|
case AT_PLATFORM:
|
||
|
|
platform = (const char*)auxv.a_un.a_val;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
close(fd);
|
||
|
|
}
|
||
|
|
#endif // WEBRTC_GLIBC_PREREQ(2, 16)
|
||
|
|
#if defined(__aarch64__)
|
||
|
|
(void)platform;
|
||
|
|
architecture = 8;
|
||
|
|
if ((hwcap & HWCAP_FP) != 0)
|
||
|
|
result |= kCPUFeatureVFPv3;
|
||
|
|
if ((hwcap & HWCAP_ASIMD) != 0)
|
||
|
|
result |= kCPUFeatureNEON;
|
||
|
|
#else
|
||
|
|
if (platform != NULL) {
|
||
|
|
/* expect a string in the form "v6l" or "v7l", etc.
|
||
|
|
*/
|
||
|
|
if (platform[0] == 'v' && '0' <= platform[1] && platform[1] <= '9' &&
|
||
|
|
(platform[2] == 'l' || platform[2] == 'b')) {
|
||
|
|
architecture = platform[1] - '0';
|
||
|
|
}
|
||
|
|
}
|
||
|
|
if ((hwcap & HWCAP_VFPv3) != 0)
|
||
|
|
result |= kCPUFeatureVFPv3;
|
||
|
|
if ((hwcap & HWCAP_NEON) != 0)
|
||
|
|
result |= kCPUFeatureNEON;
|
||
|
|
#endif
|
||
|
|
if (architecture >= 7)
|
||
|
|
result |= kCPUFeatureARMv7;
|
||
|
|
if (architecture >= 6)
|
||
|
|
result |= kCPUFeatureLDREXSTREX;
|
||
|
|
return result;
|
||
|
|
}
|
||
|
|
|
||
|
|
} // namespace webrtc
|
||
|
|
#endif // WEBRTC_ARCH_ARM_FAMILY
|