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Diffstat (limited to 'vendor/golang.org/x/sys/cpu/cpu.go')
| -rw-r--r-- | vendor/golang.org/x/sys/cpu/cpu.go | 287 |
1 files changed, 287 insertions, 0 deletions
diff --git a/vendor/golang.org/x/sys/cpu/cpu.go b/vendor/golang.org/x/sys/cpu/cpu.go new file mode 100644 index 0000000..b56886f --- /dev/null +++ b/vendor/golang.org/x/sys/cpu/cpu.go @@ -0,0 +1,287 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +// Package cpu implements processor feature detection for +// various CPU architectures. +package cpu + +import ( + "os" + "strings" +) + +// Initialized reports whether the CPU features were initialized. +// +// For some GOOS/GOARCH combinations initialization of the CPU features depends +// on reading an operating specific file, e.g. /proc/self/auxv on linux/arm +// Initialized will report false if reading the file fails. +var Initialized bool + +// CacheLinePad is used to pad structs to avoid false sharing. +type CacheLinePad struct{ _ [cacheLineSize]byte } + +// X86 contains the supported CPU features of the +// current X86/AMD64 platform. If the current platform +// is not X86/AMD64 then all feature flags are false. +// +// X86 is padded to avoid false sharing. Further the HasAVX +// and HasAVX2 are only set if the OS supports XMM and YMM +// registers in addition to the CPUID feature bit being set. +var X86 struct { + _ CacheLinePad + HasAES bool // AES hardware implementation (AES NI) + HasADX bool // Multi-precision add-carry instruction extensions + HasAVX bool // Advanced vector extension + HasAVX2 bool // Advanced vector extension 2 + HasAVX512 bool // Advanced vector extension 512 + HasAVX512F bool // Advanced vector extension 512 Foundation Instructions + HasAVX512CD bool // Advanced vector extension 512 Conflict Detection Instructions + HasAVX512ER bool // Advanced vector extension 512 Exponential and Reciprocal Instructions + HasAVX512PF bool // Advanced vector extension 512 Prefetch Instructions Instructions + HasAVX512VL bool // Advanced vector extension 512 Vector Length Extensions + HasAVX512BW bool // Advanced vector extension 512 Byte and Word Instructions + HasAVX512DQ bool // Advanced vector extension 512 Doubleword and Quadword Instructions + HasAVX512IFMA bool // Advanced vector extension 512 Integer Fused Multiply Add + HasAVX512VBMI bool // Advanced vector extension 512 Vector Byte Manipulation Instructions + HasAVX5124VNNIW bool // Advanced vector extension 512 Vector Neural Network Instructions Word variable precision + HasAVX5124FMAPS bool // Advanced vector extension 512 Fused Multiply Accumulation Packed Single precision + HasAVX512VPOPCNTDQ bool // Advanced vector extension 512 Double and quad word population count instructions + HasAVX512VPCLMULQDQ bool // Advanced vector extension 512 Vector carry-less multiply operations + HasAVX512VNNI bool // Advanced vector extension 512 Vector Neural Network Instructions + HasAVX512GFNI bool // Advanced vector extension 512 Galois field New Instructions + HasAVX512VAES bool // Advanced vector extension 512 Vector AES instructions + HasAVX512VBMI2 bool // Advanced vector extension 512 Vector Byte Manipulation Instructions 2 + HasAVX512BITALG bool // Advanced vector extension 512 Bit Algorithms + HasAVX512BF16 bool // Advanced vector extension 512 BFloat16 Instructions + HasBMI1 bool // Bit manipulation instruction set 1 + HasBMI2 bool // Bit manipulation instruction set 2 + HasCX16 bool // Compare and exchange 16 Bytes + HasERMS bool // Enhanced REP for MOVSB and STOSB + HasFMA bool // Fused-multiply-add instructions + HasOSXSAVE bool // OS supports XSAVE/XRESTOR for saving/restoring XMM registers. + HasPCLMULQDQ bool // PCLMULQDQ instruction - most often used for AES-GCM + HasPOPCNT bool // Hamming weight instruction POPCNT. + HasRDRAND bool // RDRAND instruction (on-chip random number generator) + HasRDSEED bool // RDSEED instruction (on-chip random number generator) + HasSSE2 bool // Streaming SIMD extension 2 (always available on amd64) + HasSSE3 bool // Streaming SIMD extension 3 + HasSSSE3 bool // Supplemental streaming SIMD extension 3 + HasSSE41 bool // Streaming SIMD extension 4 and 4.1 + HasSSE42 bool // Streaming SIMD extension 4 and 4.2 + _ CacheLinePad +} + +// ARM64 contains the supported CPU features of the +// current ARMv8(aarch64) platform. If the current platform +// is not arm64 then all feature flags are false. +var ARM64 struct { + _ CacheLinePad + HasFP bool // Floating-point instruction set (always available) + HasASIMD bool // Advanced SIMD (always available) + HasEVTSTRM bool // Event stream support + HasAES bool // AES hardware implementation + HasPMULL bool // Polynomial multiplication instruction set + HasSHA1 bool // SHA1 hardware implementation + HasSHA2 bool // SHA2 hardware implementation + HasCRC32 bool // CRC32 hardware implementation + HasATOMICS bool // Atomic memory operation instruction set + HasFPHP bool // Half precision floating-point instruction set + HasASIMDHP bool // Advanced SIMD half precision instruction set + HasCPUID bool // CPUID identification scheme registers + HasASIMDRDM bool // Rounding double multiply add/subtract instruction set + HasJSCVT bool // Javascript conversion from floating-point to integer + HasFCMA bool // Floating-point multiplication and addition of complex numbers + HasLRCPC bool // Release Consistent processor consistent support + HasDCPOP bool // Persistent memory support + HasSHA3 bool // SHA3 hardware implementation + HasSM3 bool // SM3 hardware implementation + HasSM4 bool // SM4 hardware implementation + HasASIMDDP bool // Advanced SIMD double precision instruction set + HasSHA512 bool // SHA512 hardware implementation + HasSVE bool // Scalable Vector Extensions + HasASIMDFHM bool // Advanced SIMD multiplication FP16 to FP32 + _ CacheLinePad +} + +// ARM contains the supported CPU features of the current ARM (32-bit) platform. +// All feature flags are false if: +// 1. the current platform is not arm, or +// 2. the current operating system is not Linux. +var ARM struct { + _ CacheLinePad + HasSWP bool // SWP instruction support + HasHALF bool // Half-word load and store support + HasTHUMB bool // ARM Thumb instruction set + Has26BIT bool // Address space limited to 26-bits + HasFASTMUL bool // 32-bit operand, 64-bit result multiplication support + HasFPA bool // Floating point arithmetic support + HasVFP bool // Vector floating point support + HasEDSP bool // DSP Extensions support + HasJAVA bool // Java instruction set + HasIWMMXT bool // Intel Wireless MMX technology support + HasCRUNCH bool // MaverickCrunch context switching and handling + HasTHUMBEE bool // Thumb EE instruction set + HasNEON bool // NEON instruction set + HasVFPv3 bool // Vector floating point version 3 support + HasVFPv3D16 bool // Vector floating point version 3 D8-D15 + HasTLS bool // Thread local storage support + HasVFPv4 bool // Vector floating point version 4 support + HasIDIVA bool // Integer divide instruction support in ARM mode + HasIDIVT bool // Integer divide instruction support in Thumb mode + HasVFPD32 bool // Vector floating point version 3 D15-D31 + HasLPAE bool // Large Physical Address Extensions + HasEVTSTRM bool // Event stream support + HasAES bool // AES hardware implementation + HasPMULL bool // Polynomial multiplication instruction set + HasSHA1 bool // SHA1 hardware implementation + HasSHA2 bool // SHA2 hardware implementation + HasCRC32 bool // CRC32 hardware implementation + _ CacheLinePad +} + +// MIPS64X contains the supported CPU features of the current mips64/mips64le +// platforms. If the current platform is not mips64/mips64le or the current +// operating system is not Linux then all feature flags are false. +var MIPS64X struct { + _ CacheLinePad + HasMSA bool // MIPS SIMD architecture + _ CacheLinePad +} + +// PPC64 contains the supported CPU features of the current ppc64/ppc64le platforms. +// If the current platform is not ppc64/ppc64le then all feature flags are false. +// +// For ppc64/ppc64le, it is safe to check only for ISA level starting on ISA v3.00, +// since there are no optional categories. There are some exceptions that also +// require kernel support to work (DARN, SCV), so there are feature bits for +// those as well. The struct is padded to avoid false sharing. +var PPC64 struct { + _ CacheLinePad + HasDARN bool // Hardware random number generator (requires kernel enablement) + HasSCV bool // Syscall vectored (requires kernel enablement) + IsPOWER8 bool // ISA v2.07 (POWER8) + IsPOWER9 bool // ISA v3.00 (POWER9), implies IsPOWER8 + _ CacheLinePad +} + +// S390X contains the supported CPU features of the current IBM Z +// (s390x) platform. If the current platform is not IBM Z then all +// feature flags are false. +// +// S390X is padded to avoid false sharing. Further HasVX is only set +// if the OS supports vector registers in addition to the STFLE +// feature bit being set. +var S390X struct { + _ CacheLinePad + HasZARCH bool // z/Architecture mode is active [mandatory] + HasSTFLE bool // store facility list extended + HasLDISP bool // long (20-bit) displacements + HasEIMM bool // 32-bit immediates + HasDFP bool // decimal floating point + HasETF3EH bool // ETF-3 enhanced + HasMSA bool // message security assist (CPACF) + HasAES bool // KM-AES{128,192,256} functions + HasAESCBC bool // KMC-AES{128,192,256} functions + HasAESCTR bool // KMCTR-AES{128,192,256} functions + HasAESGCM bool // KMA-GCM-AES{128,192,256} functions + HasGHASH bool // KIMD-GHASH function + HasSHA1 bool // K{I,L}MD-SHA-1 functions + HasSHA256 bool // K{I,L}MD-SHA-256 functions + HasSHA512 bool // K{I,L}MD-SHA-512 functions + HasSHA3 bool // K{I,L}MD-SHA3-{224,256,384,512} and K{I,L}MD-SHAKE-{128,256} functions + HasVX bool // vector facility + HasVXE bool // vector-enhancements facility 1 + _ CacheLinePad +} + +func init() { + archInit() + initOptions() + processOptions() +} + +// options contains the cpu debug options that can be used in GODEBUG. +// Options are arch dependent and are added by the arch specific initOptions functions. +// Features that are mandatory for the specific GOARCH should have the Required field set +// (e.g. SSE2 on amd64). +var options []option + +// Option names should be lower case. e.g. avx instead of AVX. +type option struct { + Name string + Feature *bool + Specified bool // whether feature value was specified in GODEBUG + Enable bool // whether feature should be enabled + Required bool // whether feature is mandatory and can not be disabled +} + +func processOptions() { + env := os.Getenv("GODEBUG") +field: + for env != "" { + field := "" + i := strings.IndexByte(env, ',') + if i < 0 { + field, env = env, "" + } else { + field, env = env[:i], env[i+1:] + } + if len(field) < 4 || field[:4] != "cpu." { + continue + } + i = strings.IndexByte(field, '=') + if i < 0 { + print("GODEBUG sys/cpu: no value specified for \"", field, "\"\n") + continue + } + key, value := field[4:i], field[i+1:] // e.g. "SSE2", "on" + + var enable bool + switch value { + case "on": + enable = true + case "off": + enable = false + default: + print("GODEBUG sys/cpu: value \"", value, "\" not supported for cpu option \"", key, "\"\n") + continue field + } + + if key == "all" { + for i := range options { + options[i].Specified = true + options[i].Enable = enable || options[i].Required + } + continue field + } + + for i := range options { + if options[i].Name == key { + options[i].Specified = true + options[i].Enable = enable + continue field + } + } + + print("GODEBUG sys/cpu: unknown cpu feature \"", key, "\"\n") + } + + for _, o := range options { + if !o.Specified { + continue + } + + if o.Enable && !*o.Feature { + print("GODEBUG sys/cpu: can not enable \"", o.Name, "\", missing CPU support\n") + continue + } + + if !o.Enable && o.Required { + print("GODEBUG sys/cpu: can not disable \"", o.Name, "\", required CPU feature\n") + continue + } + + *o.Feature = o.Enable + } +} |