/***************************************************************************** * cpu.c: cpu detection ***************************************************************************** * Copyright (C) 2003-2025 x264 project * * Authors: Loren Merritt * Laurent Aimar * Fiona Glaser * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02111, USA. * * This program is also available under a commercial proprietary license. * For more information, contact us at licensing@x264.com. *****************************************************************************/ #include "base.h" #if HAVE_GETAUXVAL || HAVE_ELF_AUX_INFO #include #endif #if HAVE_SYSCONF #include #endif #if SYS_LINUX #include #endif #if SYS_BEOS #include #endif #if SYS_MACOSX || SYS_FREEBSD || SYS_NETBSD || SYS_OPENBSD #include #include #endif #if SYS_OPENBSD #include #endif const x264_cpu_name_t x264_cpu_names[] = { #if ARCH_X86 || ARCH_X86_64 // {"MMX", X264_CPU_MMX}, // we don't support asm on mmx1 cpus anymore #define MMX2 X264_CPU_MMX|X264_CPU_MMX2 {"MMX2", MMX2}, {"MMXEXT", MMX2}, {"SSE", MMX2|X264_CPU_SSE}, #define SSE2 MMX2|X264_CPU_SSE|X264_CPU_SSE2 {"SSE2Slow", SSE2|X264_CPU_SSE2_IS_SLOW}, {"SSE2", SSE2}, {"SSE2Fast", SSE2|X264_CPU_SSE2_IS_FAST}, {"LZCNT", SSE2|X264_CPU_LZCNT}, {"SSE3", SSE2|X264_CPU_SSE3}, {"SSSE3", SSE2|X264_CPU_SSE3|X264_CPU_SSSE3}, {"SSE4.1", SSE2|X264_CPU_SSE3|X264_CPU_SSSE3|X264_CPU_SSE4}, {"SSE4", SSE2|X264_CPU_SSE3|X264_CPU_SSSE3|X264_CPU_SSE4}, {"SSE4.2", SSE2|X264_CPU_SSE3|X264_CPU_SSSE3|X264_CPU_SSE4|X264_CPU_SSE42}, #define AVX SSE2|X264_CPU_SSE3|X264_CPU_SSSE3|X264_CPU_SSE4|X264_CPU_SSE42|X264_CPU_AVX {"AVX", AVX}, {"XOP", AVX|X264_CPU_XOP}, {"FMA4", AVX|X264_CPU_FMA4}, {"FMA3", AVX|X264_CPU_FMA3}, {"BMI1", AVX|X264_CPU_LZCNT|X264_CPU_BMI1}, {"BMI2", AVX|X264_CPU_LZCNT|X264_CPU_BMI1|X264_CPU_BMI2}, #define AVX2 AVX|X264_CPU_FMA3|X264_CPU_LZCNT|X264_CPU_BMI1|X264_CPU_BMI2|X264_CPU_AVX2 {"AVX2", AVX2}, {"AVX512", AVX2|X264_CPU_AVX512}, #undef AVX2 #undef AVX #undef SSE2 #undef MMX2 {"Cache32", X264_CPU_CACHELINE_32}, {"Cache64", X264_CPU_CACHELINE_64}, {"SlowAtom", X264_CPU_SLOW_ATOM}, {"SlowPshufb", X264_CPU_SLOW_PSHUFB}, {"SlowPalignr", X264_CPU_SLOW_PALIGNR}, {"SlowShuffle", X264_CPU_SLOW_SHUFFLE}, {"UnalignedStack", X264_CPU_STACK_MOD4}, #elif ARCH_PPC {"Altivec", X264_CPU_ALTIVEC}, #elif ARCH_ARM {"ARMv6", X264_CPU_ARMV6}, {"NEON", X264_CPU_NEON}, {"FastNeonMRC", X264_CPU_FAST_NEON_MRC}, #elif ARCH_AARCH64 {"ARMv8", X264_CPU_ARMV8}, {"NEON", X264_CPU_NEON}, {"DotProd", X264_CPU_DOTPROD}, {"I8MM", X264_CPU_I8MM}, {"SVE", X264_CPU_SVE}, {"SVE2", X264_CPU_SVE2}, #elif ARCH_MIPS {"MSA", X264_CPU_MSA}, #elif ARCH_LOONGARCH {"LSX", X264_CPU_LSX}, {"LASX", X264_CPU_LASX}, #endif {"", 0}, }; static unsigned long x264_getauxval( unsigned long type ) { #if HAVE_GETAUXVAL return getauxval( type ); #elif HAVE_ELF_AUX_INFO unsigned long aux = 0; elf_aux_info( type, &aux, sizeof(aux) ); return aux; #else return 0; #endif } #if ((HAVE_ALTIVEC && SYS_LINUX) || (HAVE_ARMV6 && !HAVE_NEON)) && !(HAVE_GETAUXVAL || HAVE_ELF_AUX_INFO) #include #include static sigjmp_buf jmpbuf; static volatile sig_atomic_t canjump = 0; static void sigill_handler( int sig ) { if( !canjump ) { signal( sig, SIG_DFL ); raise( sig ); } canjump = 0; siglongjmp( jmpbuf, 1 ); } #endif #if HAVE_MMX int x264_cpu_cpuid_test( void ); void x264_cpu_cpuid( uint32_t op, uint32_t *eax, uint32_t *ebx, uint32_t *ecx, uint32_t *edx ); uint64_t x264_cpu_xgetbv( int xcr ); uint32_t x264_cpu_detect( void ) { uint32_t cpu = 0; uint32_t eax, ebx, ecx, edx; uint32_t vendor[4] = {0}; uint32_t max_extended_cap, max_basic_cap; #if !ARCH_X86_64 if( !x264_cpu_cpuid_test() ) return 0; #endif x264_cpu_cpuid( 0, &max_basic_cap, vendor+0, vendor+2, vendor+1 ); if( max_basic_cap == 0 ) return 0; x264_cpu_cpuid( 1, &eax, &ebx, &ecx, &edx ); if( edx&0x00800000 ) cpu |= X264_CPU_MMX; else return cpu; if( edx&0x02000000 ) cpu |= X264_CPU_MMX2|X264_CPU_SSE; if( edx&0x04000000 ) cpu |= X264_CPU_SSE2; if( ecx&0x00000001 ) cpu |= X264_CPU_SSE3; if( ecx&0x00000200 ) cpu |= X264_CPU_SSSE3|X264_CPU_SSE2_IS_FAST; if( ecx&0x00080000 ) cpu |= X264_CPU_SSE4; if( ecx&0x00100000 ) cpu |= X264_CPU_SSE42; if( ecx&0x08000000 ) /* XGETBV supported and XSAVE enabled by OS */ { uint64_t xcr0 = x264_cpu_xgetbv( 0 ); if( (xcr0&0x6) == 0x6 ) /* XMM/YMM state */ { if( ecx&0x10000000 ) cpu |= X264_CPU_AVX; if( ecx&0x00001000 ) cpu |= X264_CPU_FMA3; if( max_basic_cap >= 7 ) { x264_cpu_cpuid( 7, &eax, &ebx, &ecx, &edx ); if( ebx&0x00000008 ) cpu |= X264_CPU_BMI1; if( ebx&0x00000100 ) cpu |= X264_CPU_BMI2; if( ebx&0x00000020 ) cpu |= X264_CPU_AVX2; if( (xcr0&0xE0) == 0xE0 ) /* OPMASK/ZMM state */ { if( (ebx&0xD0030000) == 0xD0030000 ) cpu |= X264_CPU_AVX512; } } } } x264_cpu_cpuid( 0x80000000, &eax, &ebx, &ecx, &edx ); max_extended_cap = eax; if( max_extended_cap >= 0x80000001 ) { x264_cpu_cpuid( 0x80000001, &eax, &ebx, &ecx, &edx ); if( ecx&0x00000020 ) cpu |= X264_CPU_LZCNT; /* Supported by Intel chips starting with Haswell */ if( ecx&0x00000040 ) /* SSE4a, AMD only */ { int family = ((eax>>8)&0xf) + ((eax>>20)&0xff); cpu |= X264_CPU_SSE2_IS_FAST; /* Phenom and later CPUs have fast SSE units */ if( family == 0x14 ) { cpu &= ~X264_CPU_SSE2_IS_FAST; /* SSSE3 doesn't imply fast SSE anymore... */ cpu |= X264_CPU_SSE2_IS_SLOW; /* Bobcat has 64-bit SIMD units */ cpu |= X264_CPU_SLOW_PALIGNR; /* palignr is insanely slow on Bobcat */ } if( family == 0x16 ) { cpu |= X264_CPU_SLOW_PSHUFB; /* Jaguar's pshufb isn't that slow, but it's slow enough * compared to alternate instruction sequences that this * is equal or faster on almost all such functions. */ } } if( cpu & X264_CPU_AVX ) { if( ecx&0x00000800 ) /* XOP */ cpu |= X264_CPU_XOP; if( ecx&0x00010000 ) /* FMA4 */ cpu |= X264_CPU_FMA4; } if( !strcmp((char*)vendor, "AuthenticAMD") ) { if( edx&0x00400000 ) cpu |= X264_CPU_MMX2; if( (cpu&X264_CPU_SSE2) && !(cpu&X264_CPU_SSE2_IS_FAST) ) cpu |= X264_CPU_SSE2_IS_SLOW; /* AMD CPUs come in two types: terrible at SSE and great at it */ } } if( !strcmp((char*)vendor, "GenuineIntel") ) { x264_cpu_cpuid( 1, &eax, &ebx, &ecx, &edx ); int family = ((eax>>8)&0xf) + ((eax>>20)&0xff); int model = ((eax>>4)&0xf) + ((eax>>12)&0xf0); if( family == 6 ) { /* Detect Atom CPU */ if( model == 28 ) { cpu |= X264_CPU_SLOW_ATOM; cpu |= X264_CPU_SLOW_PSHUFB; } /* Conroe has a slow shuffle unit. Check the model number to make sure not * to include crippled low-end Penryns and Nehalems that don't have SSE4. */ else if( (cpu&X264_CPU_SSSE3) && !(cpu&X264_CPU_SSE4) && model < 23 ) cpu |= X264_CPU_SLOW_SHUFFLE; } } if( (!strcmp((char*)vendor, "GenuineIntel") || !strcmp((char*)vendor, "CyrixInstead")) && !(cpu&X264_CPU_SSE42)) { /* cacheline size is specified in 3 places, any of which may be missing */ x264_cpu_cpuid( 1, &eax, &ebx, &ecx, &edx ); int cache = (ebx&0xff00)>>5; // cflush size if( !cache && max_extended_cap >= 0x80000006 ) { x264_cpu_cpuid( 0x80000006, &eax, &ebx, &ecx, &edx ); cache = ecx&0xff; // cacheline size } if( !cache && max_basic_cap >= 2 ) { // Cache and TLB Information static const char cache32_ids[] = { 0x0a, 0x0c, 0x41, 0x42, 0x43, 0x44, 0x45, 0x82, 0x83, 0x84, 0x85, 0 }; static const char cache64_ids[] = { 0x22, 0x23, 0x25, 0x29, 0x2c, 0x46, 0x47, 0x49, 0x60, 0x66, 0x67, 0x68, 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7c, 0x7f, 0x86, 0x87, 0 }; uint32_t buf[4]; int max, i = 0; do { x264_cpu_cpuid( 2, buf+0, buf+1, buf+2, buf+3 ); max = buf[0]&0xff; buf[0] &= ~0xff; for( int j = 0; j < 4; j++ ) if( !(buf[j]>>31) ) while( buf[j] ) { if( strchr( cache32_ids, buf[j]&0xff ) ) cache = 32; if( strchr( cache64_ids, buf[j]&0xff ) ) cache = 64; buf[j] >>= 8; } } while( ++i < max ); } if( cache == 32 ) cpu |= X264_CPU_CACHELINE_32; else if( cache == 64 ) cpu |= X264_CPU_CACHELINE_64; else x264_log_internal( X264_LOG_WARNING, "unable to determine cacheline size\n" ); } #if STACK_ALIGNMENT < 16 cpu |= X264_CPU_STACK_MOD4; #endif return cpu; } #elif HAVE_ALTIVEC #if HAVE_GETAUXVAL || HAVE_ELF_AUX_INFO #define HWCAP_PPC_ALTIVEC (1U << 28) uint32_t x264_cpu_detect( void ) { uint32_t flags = 0; unsigned long hwcap = x264_getauxval( AT_HWCAP ); if ( hwcap & HWCAP_PPC_ALTIVEC ) flags |= X264_CPU_ALTIVEC; return flags; } #elif SYS_MACOSX || SYS_FREEBSD || SYS_NETBSD || SYS_OPENBSD uint32_t x264_cpu_detect( void ) { /* Thank you VLC */ uint32_t cpu = 0; #if SYS_OPENBSD int selectors[2] = { CTL_MACHDEP, CPU_ALTIVEC }; #elif SYS_MACOSX int selectors[2] = { CTL_HW, HW_VECTORUNIT }; #endif int has_altivec = 0; size_t length = sizeof( has_altivec ); #if SYS_MACOSX || SYS_OPENBSD int error = sysctl( selectors, 2, &has_altivec, &length, NULL, 0 ); #elif SYS_NETBSD int error = sysctlbyname( "machdep.altivec", &has_altivec, &length, NULL, 0 ); #else int error = sysctlbyname( "hw.altivec", &has_altivec, &length, NULL, 0 ); #endif if( error == 0 && has_altivec != 0 ) cpu |= X264_CPU_ALTIVEC; return cpu; } #elif SYS_LINUX uint32_t x264_cpu_detect( void ) { #ifdef __NO_FPRS__ return 0; #else static void (*oldsig)( int ); oldsig = signal( SIGILL, sigill_handler ); if( sigsetjmp( jmpbuf, 1 ) ) { signal( SIGILL, oldsig ); return 0; } canjump = 1; asm volatile( "mtspr 256, %0\n\t" "vand 0, 0, 0\n\t" : : "r"(-1) ); canjump = 0; signal( SIGILL, oldsig ); return X264_CPU_ALTIVEC; #endif } #else uint32_t x264_cpu_detect( void ) { return 0; } #endif #elif HAVE_ARMV6 void x264_cpu_neon_test( void ); int x264_cpu_fast_neon_mrc_test( void ); #define HWCAP_ARM_NEON (1U << 12) uint32_t x264_cpu_detect( void ) { uint32_t flags = 0; flags |= X264_CPU_ARMV6; #if HAVE_GETAUXVAL || HAVE_ELF_AUX_INFO unsigned long hwcap = x264_getauxval( AT_HWCAP ); if ( hwcap & HWCAP_ARM_NEON ) flags |= X264_CPU_NEON; #else // don't do this hack if compiled with -mfpu=neon #if !HAVE_NEON static void (* oldsig)( int ); oldsig = signal( SIGILL, sigill_handler ); if( sigsetjmp( jmpbuf, 1 ) ) { signal( SIGILL, oldsig ); return flags; } canjump = 1; x264_cpu_neon_test(); canjump = 0; signal( SIGILL, oldsig ); #endif flags |= X264_CPU_NEON; #endif // fast neon -> arm (Cortex-A9) detection relies on user access to the // cycle counter; this assumes ARMv7 performance counters. // NEON requires at least ARMv7, ARMv8 may require changes here, but // hopefully this hacky detection method will have been replaced by then. // Note that there is potential for a race condition if another program or // x264 instance disables or reinits the counters while x264 is using them, // which may result in incorrect detection and the counters stuck enabled. // right now Apple does not seem to support performance counters for this test #ifndef __MACH__ flags |= x264_cpu_fast_neon_mrc_test() ? X264_CPU_FAST_NEON_MRC : 0; #endif // TODO: write dual issue test? currently it's A8 (dual issue) vs. A9 (fast mrc) return flags; } #elif HAVE_AARCH64 #if defined(__linux__) || HAVE_ELF_AUX_INFO #define HWCAP_AARCH64_ASIMDDP (1U << 20) #define HWCAP_AARCH64_SVE (1U << 22) #define HWCAP2_AARCH64_SVE2 (1U << 1) #define HWCAP2_AARCH64_I8MM (1U << 13) static uint32_t detect_flags( void ) { uint32_t flags = 0; unsigned long hwcap = x264_getauxval( AT_HWCAP ); unsigned long hwcap2 = x264_getauxval( AT_HWCAP2 ); if ( hwcap & HWCAP_AARCH64_ASIMDDP ) flags |= X264_CPU_DOTPROD; if ( hwcap2 & HWCAP2_AARCH64_I8MM ) flags |= X264_CPU_I8MM; if ( hwcap & HWCAP_AARCH64_SVE ) flags |= X264_CPU_SVE; if ( hwcap2 & HWCAP2_AARCH64_SVE2 ) flags |= X264_CPU_SVE2; return flags; } #elif defined(__APPLE__) #include static int have_feature( const char *feature ) { int supported = 0; size_t size = sizeof(supported); if ( sysctlbyname( feature, &supported, &size, NULL, 0 ) ) return 0; return supported; } static uint32_t detect_flags( void ) { uint32_t flags = 0; if ( have_feature( "hw.optional.arm.FEAT_DotProd" ) ) flags |= X264_CPU_DOTPROD; if ( have_feature( "hw.optional.arm.FEAT_I8MM" ) ) flags |= X264_CPU_I8MM; /* No SVE and SVE2 feature detection available on Apple platforms. */ return flags; } #elif defined(_WIN32) #include static uint32_t detect_flags( void ) { uint32_t flags = 0; #ifdef PF_ARM_V82_DP_INSTRUCTIONS_AVAILABLE if ( IsProcessorFeaturePresent( PF_ARM_V82_DP_INSTRUCTIONS_AVAILABLE ) ) flags |= X264_CPU_DOTPROD; #endif #ifdef PF_ARM_SVE_INSTRUCTIONS_AVAILABLE if ( IsProcessorFeaturePresent( PF_ARM_SVE_INSTRUCTIONS_AVAILABLE ) ) flags |= X264_CPU_SVE; #endif #ifdef PF_ARM_SVE2_INSTRUCTIONS_AVAILABLE if ( IsProcessorFeaturePresent( PF_ARM_SVE2_INSTRUCTIONS_AVAILABLE ) ) flags |= X264_CPU_SVE2; #endif #ifdef PF_ARM_SVE_I8MM_INSTRUCTIONS_AVAILABLE /* There's no PF_* flag that indicates whether plain I8MM is available * or not. But if SVE_I8MM is available, that also implies that * regular I8MM is available. */ if ( IsProcessorFeaturePresent( PF_ARM_SVE_I8MM_INSTRUCTIONS_AVAILABLE ) ) flags |= X264_CPU_I8MM; #endif return flags; } #endif uint32_t x264_cpu_detect( void ) { uint32_t flags = X264_CPU_ARMV8; #if HAVE_NEON flags |= X264_CPU_NEON; #endif // If these features are enabled unconditionally in the compiler, we can // assume that they are available. #ifdef __ARM_FEATURE_DOTPROD flags |= X264_CPU_DOTPROD; #endif #ifdef __ARM_FEATURE_MATMUL_INT8 flags |= X264_CPU_I8MM; #endif #ifdef __ARM_FEATURE_SVE flags |= X264_CPU_SVE; #endif #ifdef __ARM_FEATURE_SVE2 flags |= X264_CPU_SVE2; #endif // Where possible, try to do runtime detection as well. #if defined(__linux__) || HAVE_ELF_AUX_INFO || \ defined(__APPLE__) || defined(_WIN32) flags |= detect_flags(); #endif return flags; } #elif HAVE_MSA uint32_t x264_cpu_detect( void ) { return X264_CPU_MSA; } #elif HAVE_LSX #define LA_HWCAP_LSX ( 1U << 4 ) #define LA_HWCAP_LASX ( 1U << 5 ) uint32_t x264_cpu_detect( void ) { uint32_t flags = 0; uint32_t hwcap = (uint32_t)x264_getauxval( AT_HWCAP ); if( hwcap & LA_HWCAP_LSX ) flags |= X264_CPU_LSX; if( hwcap & LA_HWCAP_LASX ) flags |= X264_CPU_LASX; return flags; } #else uint32_t x264_cpu_detect( void ) { return 0; } #endif int x264_cpu_num_processors( void ) { #if !HAVE_THREAD return 1; #elif SYS_WINDOWS return x264_pthread_num_processors_np(); #elif SYS_LINUX cpu_set_t p_aff; memset( &p_aff, 0, sizeof(p_aff) ); if( sched_getaffinity( 0, sizeof(p_aff), &p_aff ) ) return 1; #if HAVE_CPU_COUNT return CPU_COUNT(&p_aff); #else int np = 0; for( size_t bit = 0; bit < 8 * sizeof(p_aff); bit++ ) np += (((uint8_t *)&p_aff)[bit / 8] >> (bit % 8)) & 1; return np; #endif #elif SYS_BEOS system_info info; get_system_info( &info ); return info.cpu_count; #elif SYS_MACOSX int ncpu; size_t length = sizeof( ncpu ); if( sysctlbyname("hw.logicalcpu", &ncpu, &length, NULL, 0) ) { ncpu = 1; } return ncpu; #elif defined(_SC_NPROCESSORS_ONLN) return sysconf( _SC_NPROCESSORS_ONLN ); #elif defined(_SC_NPROCESSORS_CONF) return sysconf( _SC_NPROCESSORS_CONF ); #else return 1; #endif }