diff options
Diffstat (limited to 'vpx_ports/aarch64_cpudetect.c')
| -rw-r--r-- | vpx_ports/aarch64_cpudetect.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/vpx_ports/aarch64_cpudetect.c b/vpx_ports/aarch64_cpudetect.c new file mode 100644 index 000000000..539d09bb3 --- /dev/null +++ b/vpx_ports/aarch64_cpudetect.c @@ -0,0 +1,199 @@ +/* + * 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 "arm_cpudetect.h" + +#if defined(__APPLE__) +#include <sys/sysctl.h> +#endif + +#if !CONFIG_RUNTIME_CPU_DETECT + +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 + +// sysctlbyname() parameter documentation for instruction set characteristics: +// https://developer.apple.com/documentation/kernel/1387446-sysctlbyname/determining_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: +// https://learn.microsoft.com/en-us/windows/win32/api/processthreadsapi/nf-processthreadsapi-isprocessorfeaturepresent#parameters +#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_I8MM (1 << 13) + +static int arm_get_cpu_caps(void) { + int flags = 0; + unsigned long hwcap = getauxval(AT_HWCAP); +#if HAVE_NEON_I8MM + unsigned long hwcap2 = getauxval(AT_HWCAP2); +#endif // HAVE_NEON_I8MM +#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 + return flags; +} + +#elif defined(__Fuchsia__) // end __linux__ + +#include <zircon/features.h> +#include <zircon/syscalls.h> + +// Added in https://fuchsia-review.googlesource.com/c/fuchsia/+/894282. +#ifndef ZX_ARM64_FEATURE_ISA_I8MM +#define ZX_ARM64_FEATURE_ISA_I8MM ((uint32_t)(1u << 19)) +#endif +// Added in https://fuchsia-review.googlesource.com/c/fuchsia/+/895083. +#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; + } + + return flags; +} |