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/*
* Copyright (c) 2023 The WebM 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 "./vpx_config.h"
#include "vpx_ports/arm.h"
#include "vpx_ports/arm_cpudetect.h"
#if defined(__APPLE__)
#include <sys/sysctl.h>
#endif
#if !CONFIG_RUNTIME_CPU_DETECT || defined(__OpenBSD__)
static int arm_get_cpu_caps(void) {
// This function should actually be a no-op. There is no way to adjust any of
// these because the RTCD tables do not exist: the functions are called
// statically.
int flags = 0;
#if HAVE_NEON
flags |= HAS_NEON;
#endif // HAVE_NEON
return flags;
}
#elif defined(__APPLE__) // end !CONFIG_RUNTIME_CPU_DETECT || defined(__OpenBSD__)
// sysctlbyname() parameter documentation for instruction set characteristics:
static INLINE int64_t have_feature(const char *feature) {
int64_t feature_present = 0;
size_t size = sizeof(feature_present);
if (sysctlbyname(feature, &feature_present, &size, NULL, 0) != 0) {
return 0;
}
return feature_present;
}
static int arm_get_cpu_caps(void) {
int flags = 0;
#if HAVE_NEON
flags |= HAS_NEON;
#endif // HAVE_NEON
#if HAVE_NEON_DOTPROD
if (have_feature("hw.optional.arm.FEAT_DotProd")) {
flags |= HAS_NEON_DOTPROD;
}
#endif // HAVE_NEON_DOTPROD
#if HAVE_NEON_I8MM
if (have_feature("hw.optional.arm.FEAT_I8MM")) {
flags |= HAS_NEON_I8MM;
}
#endif // HAVE_NEON_I8MM
return flags;
}
#elif defined(_WIN32) // end __APPLE__
static int arm_get_cpu_caps(void) {
int flags = 0;
// IsProcessorFeaturePresent() parameter documentation:
#if HAVE_NEON
flags |= HAS_NEON; // Neon is mandatory in Armv8.0-A.
#endif // HAVE_NEON
#if HAVE_NEON_DOTPROD
// Support for PF_ARM_V82_DP_INSTRUCTIONS_AVAILABLE was added in Windows SDK
// 20348, supported by Windows 11 and Windows Server 2022.
#if defined(PF_ARM_V82_DP_INSTRUCTIONS_AVAILABLE)
if (IsProcessorFeaturePresent(PF_ARM_V82_DP_INSTRUCTIONS_AVAILABLE)) {
flags |= HAS_NEON_DOTPROD;
}
#endif // defined(PF_ARM_V82_DP_INSTRUCTIONS_AVAILABLE)
#endif // HAVE_NEON_DOTPROD
// No I8MM or SVE feature detection available on Windows at time of writing.
return flags;
}
#elif defined(ANDROID_USE_CPU_FEATURES_LIB)
static int arm_get_cpu_caps(void) {
int flags = 0;
#if HAVE_NEON
flags |= HAS_NEON; // Neon is mandatory in Armv8.0-A.
#endif // HAVE_NEON
return flags;
}
#elif defined(__linux__) // end defined(VPX_USE_ANDROID_CPU_FEATURES)
#include <sys/auxv.h>
// Define hwcap values ourselves: building with an old auxv header where these
// hwcap values are not defined should not prevent features from being enabled.
#define VPX_AARCH64_HWCAP_ASIMDDP (1 << 20)
#define VPX_AARCH64_HWCAP_SVE (1 << 22)
#define VPX_AARCH64_HWCAP2_SVE2 (1 << 1)
#define VPX_AARCH64_HWCAP2_I8MM (1 << 13)
static int arm_get_cpu_caps(void) {
int flags = 0;
#if HAVE_NEON_DOTPROD || HAVE_SVE
unsigned long hwcap = getauxval(AT_HWCAP);
#endif // HAVE_NEON_DOTPROD || HAVE_SVE
#if HAVE_NEON_I8MM || HAVE_SVE2
unsigned long hwcap2 = getauxval(AT_HWCAP2);
#endif // HAVE_NEON_I8MM || HAVE_SVE2
#if HAVE_NEON
flags |= HAS_NEON; // Neon is mandatory in Armv8.0-A.
#endif // HAVE_NEON
#if HAVE_NEON_DOTPROD
if (hwcap & VPX_AARCH64_HWCAP_ASIMDDP) {
flags |= HAS_NEON_DOTPROD;
}
#endif // HAVE_NEON_DOTPROD
#if HAVE_NEON_I8MM
if (hwcap2 & VPX_AARCH64_HWCAP2_I8MM) {
flags |= HAS_NEON_I8MM;
}
#endif // HAVE_NEON_I8MM
#if HAVE_SVE
if (hwcap & VPX_AARCH64_HWCAP_SVE) {
flags |= HAS_SVE;
}
#endif // HAVE_SVE
#if HAVE_SVE2
if (hwcap2 & VPX_AARCH64_HWCAP2_SVE2) {
flags |= HAS_SVE2;
}
#endif // HAVE_SVE2
return flags;
}
#elif defined(__Fuchsia__) // end __linux__
#include <zircon/features.h>
#include <zircon/syscalls.h>
#ifndef ZX_ARM64_FEATURE_ISA_I8MM
#define ZX_ARM64_FEATURE_ISA_I8MM ((uint32_t)(1u << 19))
#endif
#ifndef ZX_ARM64_FEATURE_ISA_SVE
#define ZX_ARM64_FEATURE_ISA_SVE ((uint32_t)(1u << 20))
#endif
static int arm_get_cpu_caps(void) {
int flags = 0;
#if HAVE_NEON
flags |= HAS_NEON; // Neon is mandatory in Armv8.0-A.
#endif // HAVE_NEON
uint32_t features;
zx_status_t status = zx_system_get_features(ZX_FEATURE_KIND_CPU, &features);
if (status != ZX_OK) {
return flags;
}
#if HAVE_NEON_DOTPROD
if (features & ZX_ARM64_FEATURE_ISA_DP) {
flags |= HAS_NEON_DOTPROD;
}
#endif // HAVE_NEON_DOTPROD
#if HAVE_NEON_I8MM
if (features & ZX_ARM64_FEATURE_ISA_I8MM) {
flags |= HAS_NEON_I8MM;
}
#endif // HAVE_NEON_I8MM
#if HAVE_SVE
if (features & ZX_ARM64_FEATURE_ISA_SVE) {
flags |= HAS_SVE;
}
#endif // HAVE_SVE
return flags;
}
#else // end __Fuchsia__
#error \
"Runtime CPU detection selected, but no CPU detection method available" \
"for your platform. Rerun configure with --disable-runtime-cpu-detect."
#endif
int arm_cpu_caps(void) {
int flags = 0;
if (!arm_cpu_env_flags(&flags)) {
flags = arm_get_cpu_caps() & arm_cpu_env_mask();
}
// Restrict flags: FEAT_I8MM assumes that FEAT_DotProd is available.
if (!(flags & HAS_NEON_DOTPROD)) {
flags &= ~HAS_NEON_I8MM;
}
// Restrict flags: FEAT_SVE assumes that FEAT_{DotProd,I8MM} are available.
if (!(flags & HAS_NEON_DOTPROD)) {
flags &= ~HAS_SVE;
}
if (!(flags & HAS_NEON_I8MM)) {
flags &= ~HAS_SVE;
}
// Restrict flags: FEAT_SVE2 assumes that FEAT_SVE is available.
if (!(flags & HAS_SVE)) {
flags &= ~HAS_SVE2;
}
return flags;
}