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chromium / external / github.com / klauspost / cpuid / 65b27688b98c471a6e753703ca16c3325d20ef80 / . / cpuid.go
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// Copyright (c) 2015 Klaus Post, released under MIT License. See LICENSE file.
// Package cpuid provides information about the CPU running the current program.
//
// CPU features are detected on startup, and kept for fast access through the life of the application.
// Currently x86 / x64 (AMD64) as well as arm64 is supported.
//
// You can access the CPU information by accessing the shared CPU variable of the cpuid library.
//
// Package home: https://github.com/klauspost/cpuid
package cpuid
import (
"flag"
"fmt"
"math"
"os"
"runtime"
"strings"
)
// AMD refererence: https://www.amd.com/system/files/TechDocs/25481.pdf
// and Processor Programming Reference (PPR)
// Vendor is a representation of a CPU vendor.
type Vendor int
const (
VendorUnknown Vendor = iota
Intel
AMD
VIA
Transmeta
NSC
KVM // Kernel-based Virtual Machine
MSVM // Microsoft Hyper-V or Windows Virtual PC
VMware
XenHVM
Bhyve
Hygon
SiS
RDC
Ampere
ARM
Broadcom
Cavium
DEC
Fujitsu
Infineon
Motorola
NVIDIA
AMCC
Qualcomm
Marvell
lastVendor
)
//go:generate stringer -type=FeatureID,Vendor
// FeatureID is the ID of a specific cpu feature.
type FeatureID int
const (
// Keep index -1 as unknown
UNKNOWN = -1
// Add features
ADX FeatureID = iota // Intel ADX (Multi-Precision Add-Carry Instruction Extensions)
AESNI // Advanced Encryption Standard New Instructions
AMD3DNOW // AMD 3DNOW
AMD3DNOWEXT // AMD 3DNowExt
AMXBF16 // Tile computational operations on BFLOAT16 numbers
AMXINT8 // Tile computational operations on 8-bit integers
AMXTILE // Tile architecture
AVX // AVX functions
AVX2 // AVX2 functions
AVX512BF16 // AVX-512 BFLOAT16 Instructions
AVX512BITALG // AVX-512 Bit Algorithms
AVX512BW // AVX-512 Byte and Word Instructions
AVX512CD // AVX-512 Conflict Detection Instructions
AVX512DQ // AVX-512 Doubleword and Quadword Instructions
AVX512ER // AVX-512 Exponential and Reciprocal Instructions
AVX512F // AVX-512 Foundation
AVX512FP16 // AVX-512 FP16 Instructions
AVX512IFMA // AVX-512 Integer Fused Multiply-Add Instructions
AVX512PF // AVX-512 Prefetch Instructions
AVX512VBMI // AVX-512 Vector Bit Manipulation Instructions
AVX512VBMI2 // AVX-512 Vector Bit Manipulation Instructions, Version 2
AVX512VL // AVX-512 Vector Length Extensions
AVX512VNNI // AVX-512 Vector Neural Network Instructions
AVX512VP2INTERSECT // AVX-512 Intersect for D/Q
AVX512VPOPCNTDQ // AVX-512 Vector Population Count Doubleword and Quadword
AVXSLOW // Indicates the CPU performs 2 128 bit operations instead of one.
BMI1 // Bit Manipulation Instruction Set 1
BMI2 // Bit Manipulation Instruction Set 2
CETIBT // Intel CET Indirect Branch Tracking
CETSS // Intel CET Shadow Stack
CLDEMOTE // Cache Line Demote
CLMUL // Carry-less Multiplication
CLZERO // CLZERO instruction supported
CMOV // i686 CMOV
CMPXCHG8 // CMPXCHG8 instruction
CPBOOST // Core Performance Boost
CX16 // CMPXCHG16B Instruction
ENQCMD // Enqueue Command
ERMS // Enhanced REP MOVSB/STOSB
F16C // Half-precision floating-point conversion
FMA3 // Intel FMA 3. Does not imply AVX.
FMA4 // Bulldozer FMA4 functions
FXSR // FXSAVE, FXRESTOR instructions, CR4 bit 9
FXSROPT // FXSAVE/FXRSTOR optimizations
GFNI // Galois Field New Instructions
HLE // Hardware Lock Elision
HTT // Hyperthreading (enabled)
HWA // Hardware assert supported. Indicates support for MSRC001_10
HYPERVISOR // This bit has been reserved by Intel & AMD for use by hypervisors
IBPB // Indirect Branch Restricted Speculation (IBRS) and Indirect Branch Predictor Barrier (IBPB)
IBS // Instruction Based Sampling (AMD)
IBSBRNTRGT // Instruction Based Sampling Feature (AMD)
IBSFETCHSAM // Instruction Based Sampling Feature (AMD)
IBSFFV // Instruction Based Sampling Feature (AMD)
IBSOPCNT // Instruction Based Sampling Feature (AMD)
IBSOPCNTEXT // Instruction Based Sampling Feature (AMD)
IBSOPSAM // Instruction Based Sampling Feature (AMD)
IBSRDWROPCNT // Instruction Based Sampling Feature (AMD)
IBSRIPINVALIDCHK // Instruction Based Sampling Feature (AMD)
INT_WBINVD // WBINVD/WBNOINVD are interruptible.
INVLPGB // NVLPGB and TLBSYNC instruction supported
LAHF // LAHF/SAHF in long mode
LZCNT // LZCNT instruction
MCAOVERFLOW // MCA overflow recovery support.
MCOMMIT // MCOMMIT instruction supported
MMX // standard MMX
MMXEXT // SSE integer functions or AMD MMX ext
MOVBE // MOVBE instruction (big-endian)
MOVDIR64B // Move 64 Bytes as Direct Store
MOVDIRI // Move Doubleword as Direct Store
MPX // Intel MPX (Memory Protection Extensions)
MSRIRC // Instruction Retired Counter MSR available
NX // NX (No-Execute) bit
OSXSAVE // XSAVE enabled by OS
POPCNT // POPCNT instruction
RDPRU // RDPRU instruction supported
RDRAND // RDRAND instruction is available
RDSEED // RDSEED instruction is available
RDTSCP // RDTSCP Instruction
RTM // Restricted Transactional Memory
RTM_ALWAYS_ABORT // Indicates that the loaded microcode is forcing RTM abort.
SCE // SYSENTER and SYSEXIT instructions
SERIALIZE // Serialize Instruction Execution
SGX // Software Guard Extensions
SGXLC // Software Guard Extensions Launch Control
SHA // Intel SHA Extensions
SSE // SSE functions
SSE2 // P4 SSE functions
SSE3 // Prescott SSE3 functions
SSE4 // Penryn SSE4.1 functions
SSE42 // Nehalem SSE4.2 functions
SSE4A // AMD Barcelona microarchitecture SSE4a instructions
SSSE3 // Conroe SSSE3 functions
STIBP // Single Thread Indirect Branch Predictors
SUCCOR // Software uncorrectable error containment and recovery capability.
TBM // AMD Trailing Bit Manipulation
TSXLDTRK // Intel TSX Suspend Load Address Tracking
VAES // Vector AES
VMX // Virtual Machine Extensions
VPCLMULQDQ // Carry-Less Multiplication Quadword
WAITPKG // TPAUSE, UMONITOR, UMWAIT
WBNOINVD // Write Back and Do Not Invalidate Cache
X87 // FPU
XOP // Bulldozer XOP functions
XSAVE // XSAVE, XRESTOR, XSETBV, XGETBV
// ARM features:
AESARM // AES instructions
ARMCPUID // Some CPU ID registers readable at user-level
ASIMD // Advanced SIMD
ASIMDDP // SIMD Dot Product
ASIMDHP // Advanced SIMD half-precision floating point
ASIMDRDM // Rounding Double Multiply Accumulate/Subtract (SQRDMLAH/SQRDMLSH)
ATOMICS // Large System Extensions (LSE)
CRC32 // CRC32/CRC32C instructions
DCPOP // Data cache clean to Point of Persistence (DC CVAP)
EVTSTRM // Generic timer
FCMA // Floatin point complex number addition and multiplication
FP // Single-precision and double-precision floating point
FPHP // Half-precision floating point
GPA // Generic Pointer Authentication
JSCVT // Javascript-style double->int convert (FJCVTZS)
LRCPC // Weaker release consistency (LDAPR, etc)
PMULL // Polynomial Multiply instructions (PMULL/PMULL2)
SHA1 // SHA-1 instructions (SHA1C, etc)
SHA2 // SHA-2 instructions (SHA256H, etc)
SHA3 // SHA-3 instructions (EOR3, RAXI, XAR, BCAX)
SHA512 // SHA512 instructions
SM3 // SM3 instructions
SM4 // SM4 instructions
SVE // Scalable Vector Extension
// Keep it last. It automatically defines the size of []flagSet
lastID
firstID FeatureID = UNKNOWN + 1
)
// CPUInfo contains information about the detected system CPU.
type CPUInfo struct {
BrandName string // Brand name reported by the CPU
VendorID Vendor // Comparable CPU vendor ID
VendorString string // Raw vendor string.
featureSet flagSet // Features of the CPU
PhysicalCores int // Number of physical processor cores in your CPU. Will be 0 if undetectable.
ThreadsPerCore int // Number of threads per physical core. Will be 1 if undetectable.
LogicalCores int // Number of physical cores times threads that can run on each core through the use of hyperthreading. Will be 0 if undetectable.
Family int // CPU family number
Model int // CPU model number
CacheLine int // Cache line size in bytes. Will be 0 if undetectable.
Hz int64 // Clock speed, if known, 0 otherwise. Will attempt to contain base clock speed.
BoostFreq int64 // Max clock speed, if known, 0 otherwise
Cache struct {
L1I int // L1 Instruction Cache (per core or shared). Will be -1 if undetected
L1D int // L1 Data Cache (per core or shared). Will be -1 if undetected
L2 int // L2 Cache (per core or shared). Will be -1 if undetected
L3 int // L3 Cache (per core, per ccx or shared). Will be -1 if undetected
}
SGX SGXSupport
maxFunc uint32
maxExFunc uint32
}
var cpuid func(op uint32) (eax, ebx, ecx, edx uint32)
var cpuidex func(op, op2 uint32) (eax, ebx, ecx, edx uint32)
var xgetbv func(index uint32) (eax, edx uint32)
var rdtscpAsm func() (eax, ebx, ecx, edx uint32)
var darwinHasAVX512 = func() bool { return false }
// CPU contains information about the CPU as detected on startup,
// or when Detect last was called.
//
// Use this as the primary entry point to you data.
var CPU CPUInfo
func init() {
initCPU()
Detect()
}
// Detect will re-detect current CPU info.
// This will replace the content of the exported CPU variable.
//
// Unless you expect the CPU to change while you are running your program
// you should not need to call this function.
// If you call this, you must ensure that no other goroutine is accessing the
// exported CPU variable.
func Detect() {
// Set defaults
CPU.ThreadsPerCore = 1
CPU.Cache.L1I = -1
CPU.Cache.L1D = -1
CPU.Cache.L2 = -1
CPU.Cache.L3 = -1
safe := true
if detectArmFlag != nil {
safe = !*detectArmFlag
}
addInfo(&CPU, safe)
if displayFeats != nil && *displayFeats {
fmt.Println("cpu features:", strings.Join(CPU.FeatureSet(), ","))
// Exit with non-zero so tests will print value.
os.Exit(1)
}
if disableFlag != nil {
s := strings.Split(*disableFlag, ",")
for _, feat := range s {
feat := ParseFeature(strings.TrimSpace(feat))
if feat != UNKNOWN {
CPU.featureSet.unset(feat)
}
}
}
}
// DetectARM will detect ARM64 features.
// This is NOT done automatically since it can potentially crash
// if the OS does not handle the command.
// If in the future this can be done safely this function may not
// do anything.
func DetectARM() {
addInfo(&CPU, false)
}
var detectArmFlag *bool
var displayFeats *bool
var disableFlag *string
// Flags will enable flags.
// This must be called *before* flag.Parse AND
// Detect must be called after the flags have been parsed.
// Note that this means that any detection used in init() functions
// will not contain these flags.
func Flags() {
disableFlag = flag.String("cpu.disable", "", "disable cpu features; comma separated list")
displayFeats = flag.Bool("cpu.features", false, "lists cpu features and exits")
detectArmFlag = flag.Bool("cpu.arm", false, "allow ARM features to be detected; can potentially crash")
}
// Supports returns whether the CPU supports all of the requested features.
func (c CPUInfo) Supports(ids ...FeatureID) bool {
for _, id := range ids {
if !c.featureSet.inSet(id) {
return false
}
}
return true
}
// Has allows for checking a single feature.
// Should be inlined by the compiler.
func (c CPUInfo) Has(id FeatureID) bool {
return c.featureSet.inSet(id)
}
// https://en.wikipedia.org/wiki/X86-64#Microarchitecture_levels
var level1Features = flagSetWith(CMOV, CMPXCHG8, X87, FXSR, MMX, SCE, SSE, SSE2)
var level2Features = flagSetWith(CMOV, CMPXCHG8, X87, FXSR, MMX, SCE, SSE, SSE2, CX16, LAHF, POPCNT, SSE3, SSE4, SSE42, SSSE3)
var level3Features = flagSetWith(CMOV, CMPXCHG8, X87, FXSR, MMX, SCE, SSE, SSE2, CX16, LAHF, POPCNT, SSE3, SSE4, SSE42, SSSE3, AVX, AVX2, BMI1, BMI2, F16C, FMA3, LZCNT, MOVBE, OSXSAVE)
var level4Features = flagSetWith(CMOV, CMPXCHG8, X87, FXSR, MMX, SCE, SSE, SSE2, CX16, LAHF, POPCNT, SSE3, SSE4, SSE42, SSSE3, AVX, AVX2, BMI1, BMI2, F16C, FMA3, LZCNT, MOVBE, OSXSAVE, AVX512F, AVX512BW, AVX512CD, AVX512DQ, AVX512VL)
// X64Level returns the microarchitecture level detected on the CPU.
// If features are lacking or non x64 mode, 0 is returned.
// See https://en.wikipedia.org/wiki/X86-64#Microarchitecture_levels
func (c CPUInfo) X64Level() int {
if c.featureSet.hasSet(level4Features) {
return 4
}
if c.featureSet.hasSet(level3Features) {
return 3
}
if c.featureSet.hasSet(level2Features) {
return 2
}
if c.featureSet.hasSet(level1Features) {
return 1
}
return 0
}
// Disable will disable one or several features.
func (c *CPUInfo) Disable(ids ...FeatureID) bool {
for _, id := range ids {
c.featureSet.unset(id)
}
return true
}
// Enable will disable one or several features even if they were undetected.
// This is of course not recommended for obvious reasons.
func (c *CPUInfo) Enable(ids ...FeatureID) bool {
for _, id := range ids {
c.featureSet.set(id)
}
return true
}
// IsVendor returns true if vendor is recognized as Intel
func (c CPUInfo) IsVendor(v Vendor) bool {
return c.VendorID == v
}
func (c CPUInfo) FeatureSet() []string {
s := make([]string, 0)
s = append(s, c.featureSet.Strings()...)
return s
}
// RTCounter returns the 64-bit time-stamp counter
// Uses the RDTSCP instruction. The value 0 is returned
// if the CPU does not support the instruction.
func (c CPUInfo) RTCounter() uint64 {
if !c.Supports(RDTSCP) {
return 0
}
a, _, _, d := rdtscpAsm()
return uint64(a) | (uint64(d) << 32)
}
// Ia32TscAux returns the IA32_TSC_AUX part of the RDTSCP.
// This variable is OS dependent, but on Linux contains information
// about the current cpu/core the code is running on.
// If the RDTSCP instruction isn't supported on the CPU, the value 0 is returned.
func (c CPUInfo) Ia32TscAux() uint32 {
if !c.Supports(RDTSCP) {
return 0
}
_, _, ecx, _ := rdtscpAsm()
return ecx
}
// LogicalCPU will return the Logical CPU the code is currently executing on.
// This is likely to change when the OS re-schedules the running thread
// to another CPU.
// If the current core cannot be detected, -1 will be returned.
func (c CPUInfo) LogicalCPU() int {
if c.maxFunc < 1 {
return -1
}
_, ebx, _, _ := cpuid(1)
return int(ebx >> 24)
}
// frequencies tries to compute the clock speed of the CPU. If leaf 15 is
// supported, use it, otherwise parse the brand string. Yes, really.
func (c *CPUInfo) frequencies() {
c.Hz, c.BoostFreq = 0, 0
mfi := maxFunctionID()
if mfi >= 0x15 {
eax, ebx, ecx, _ := cpuid(0x15)
if eax != 0 && ebx != 0 && ecx != 0 {
c.Hz = (int64(ecx) * int64(ebx)) / int64(eax)
}
}
if mfi >= 0x16 {
a, b, _, _ := cpuid(0x16)
// Base...
if a&0xffff > 0 {
c.Hz = int64(a&0xffff) * 1_000_000
}
// Boost...
if b&0xffff > 0 {
c.BoostFreq = int64(b&0xffff) * 1_000_000
}
}
if c.Hz > 0 {
return
}
// computeHz determines the official rated speed of a CPU from its brand
// string. This insanity is *actually the official documented way to do
// this according to Intel*, prior to leaf 0x15 existing. The official
// documentation only shows this working for exactly `x.xx` or `xxxx`
// cases, e.g., `2.50GHz` or `1300MHz`; this parser will accept other
// sizes.
model := c.BrandName
hz := strings.LastIndex(model, "Hz")
if hz < 3 {
return
}
var multiplier int64
switch model[hz-1] {
case 'M':
multiplier = 1000 * 1000
case 'G':
multiplier = 1000 * 1000 * 1000
case 'T':
multiplier = 1000 * 1000 * 1000 * 1000
}
if multiplier == 0 {
return
}
freq := int64(0)
divisor := int64(0)
decimalShift := int64(1)
var i int
for i = hz - 2; i >= 0 && model[i] != ' '; i-- {
if model[i] >= '0' && model[i] <= '9' {
freq += int64(model[i]-'0') * decimalShift
decimalShift *= 10
} else if model[i] == '.' {
if divisor != 0 {
return
}
divisor = decimalShift
} else {
return
}
}
// we didn't find a space
if i < 0 {
return
}
if divisor != 0 {
c.Hz = (freq * multiplier) / divisor
return
}
c.Hz = freq * multiplier
}
// VM Will return true if the cpu id indicates we are in
// a virtual machine.
func (c CPUInfo) VM() bool {
return CPU.featureSet.inSet(HYPERVISOR)
}
// flags contains detected cpu features and characteristics
type flags uint64
// log2(bits_in_uint64)
const flagBitsLog2 = 6
const flagBits = 1 << flagBitsLog2
const flagMask = flagBits - 1
// flagSet contains detected cpu features and characteristics in an array of flags
type flagSet [(lastID + flagMask) / flagBits]flags
func (s flagSet) inSet(feat FeatureID) bool {
return s[feat>>flagBitsLog2]&(1<<(feat&flagMask)) != 0
}
func (s *flagSet) set(feat FeatureID) {
s[feat>>flagBitsLog2] |= 1 << (feat & flagMask)
}
// setIf will set a feature if boolean is true.
func (s *flagSet) setIf(cond bool, features ...FeatureID) {
if cond {
for _, offset := range features {
s[offset>>flagBitsLog2] |= 1 << (offset & flagMask)
}
}
}
func (s *flagSet) unset(offset FeatureID) {
bit := flags(1 << (offset & flagMask))
s[offset>>flagBitsLog2] = s[offset>>flagBitsLog2] & ^bit
}
// or with another flagset.
func (s *flagSet) or(other flagSet) {
for i, v := range other[:] {
s[i] |= v
}
}
// hasSet returns whether all features are present.
func (s flagSet) hasSet(other flagSet) bool {
for i, v := range other[:] {
if s[i]&v != v {
return false
}
}
return true
}
func flagSetWith(feat ...FeatureID) flagSet {
var res flagSet
for _, f := range feat {
res.set(f)
}
return res
}
// ParseFeature will parse the string and return the ID of the matching feature.
// Will return UNKNOWN if not found.
func ParseFeature(s string) FeatureID {
s = strings.ToUpper(s)
for i := firstID; i < lastID; i++ {
if i.String() == s {
return i
}
}
return UNKNOWN
}
// Strings returns an array of the detected features for FlagsSet.
func (s flagSet) Strings() []string {
if len(s) == 0 {
return []string{""}
}
r := make([]string, 0)
for i := firstID; i < lastID; i++ {
if s.inSet(i) {
r = append(r, i.String())
}
}
return r
}
func maxExtendedFunction() uint32 {
eax, _, _, _ := cpuid(0x80000000)
return eax
}
func maxFunctionID() uint32 {
a, _, _, _ := cpuid(0)
return a
}
func brandName() string {
if maxExtendedFunction() >= 0x80000004 {
v := make([]uint32, 0, 48)
for i := uint32(0); i < 3; i++ {
a, b, c, d := cpuid(0x80000002 + i)
v = append(v, a, b, c, d)
}
return strings.Trim(string(valAsString(v...)), " ")
}
return "unknown"
}
func threadsPerCore() int {
mfi := maxFunctionID()
vend, _ := vendorID()
if mfi < 0x4 || (vend != Intel && vend != AMD) {
return 1
}
if mfi < 0xb {
if vend != Intel {
return 1
}
_, b, _, d := cpuid(1)
if (d & (1 << 28)) != 0 {
// v will contain logical core count
v := (b >> 16) & 255
if v > 1 {
a4, _, _, _ := cpuid(4)
// physical cores
v2 := (a4 >> 26) + 1
if v2 > 0 {
return int(v) / int(v2)
}
}
}
return 1
}
_, b, _, _ := cpuidex(0xb, 0)
if b&0xffff == 0 {
if vend == AMD {
// Workaround for AMD returning 0, assume 2 if >= Zen 2
// It will be more correct than not.
fam, _ := familyModel()
_, _, _, d := cpuid(1)
if (d&(1<<28)) != 0 && fam >= 23 {
return 2
}
}
return 1
}
return int(b & 0xffff)
}
func logicalCores() int {
mfi := maxFunctionID()
v, _ := vendorID()
switch v {
case Intel:
// Use this on old Intel processors
if mfi < 0xb {
if mfi < 1 {
return 0
}
// CPUID.1:EBX[23:16] represents the maximum number of addressable IDs (initial APIC ID)
// that can be assigned to logical processors in a physical package.
// The value may not be the same as the number of logical processors that are present in the hardware of a physical package.
_, ebx, _, _ := cpuid(1)
logical := (ebx >> 16) & 0xff
return int(logical)
}
_, b, _, _ := cpuidex(0xb, 1)
return int(b & 0xffff)
case AMD, Hygon:
_, b, _, _ := cpuid(1)
return int((b >> 16) & 0xff)
default:
return 0
}
}
func familyModel() (int, int) {
if maxFunctionID() < 0x1 {
return 0, 0
}
eax, _, _, _ := cpuid(1)
family := ((eax >> 8) & 0xf) + ((eax >> 20) & 0xff)
model := ((eax >> 4) & 0xf) + ((eax >> 12) & 0xf0)
return int(family), int(model)
}
func physicalCores() int {
v, _ := vendorID()
switch v {
case Intel:
return logicalCores() / threadsPerCore()
case AMD, Hygon:
lc := logicalCores()
tpc := threadsPerCore()
if lc > 0 && tpc > 0 {
return lc / tpc
}
// The following is inaccurate on AMD EPYC 7742 64-Core Processor
if maxExtendedFunction() >= 0x80000008 {
_, _, c, _ := cpuid(0x80000008)
if c&0xff > 0 {
return int(c&0xff) + 1
}
}
}
return 0
}
// Except from http://en.wikipedia.org/wiki/CPUID#EAX.3D0:_Get_vendor_ID
var vendorMapping = map[string]Vendor{
"AMDisbetter!": AMD,
"AuthenticAMD": AMD,
"CentaurHauls": VIA,
"GenuineIntel": Intel,
"TransmetaCPU": Transmeta,
"GenuineTMx86": Transmeta,
"Geode by NSC": NSC,
"VIA VIA VIA ": VIA,
"KVMKVMKVMKVM": KVM,
"Microsoft Hv": MSVM,
"VMwareVMware": VMware,
"XenVMMXenVMM": XenHVM,
"bhyve bhyve ": Bhyve,
"HygonGenuine": Hygon,
"Vortex86 SoC": SiS,
"SiS SiS SiS ": SiS,
"RiseRiseRise": SiS,
"Genuine RDC": RDC,
}
func vendorID() (Vendor, string) {
_, b, c, d := cpuid(0)
v := string(valAsString(b, d, c))
vend, ok := vendorMapping[v]
if !ok {
return VendorUnknown, v
}
return vend, v
}
func cacheLine() int {
if maxFunctionID() < 0x1 {
return 0
}
_, ebx, _, _ := cpuid(1)
cache := (ebx & 0xff00) >> 5 // cflush size
if cache == 0 && maxExtendedFunction() >= 0x80000006 {
_, _, ecx, _ := cpuid(0x80000006)
cache = ecx & 0xff // cacheline size
}
// TODO: Read from Cache and TLB Information
return int(cache)
}
func (c *CPUInfo) cacheSize() {
c.Cache.L1D = -1
c.Cache.L1I = -1
c.Cache.L2 = -1
c.Cache.L3 = -1
vendor, _ := vendorID()
switch vendor {
case Intel:
if maxFunctionID() < 4 {
return
}
c.Cache.L1I, c.Cache.L1D, c.Cache.L2, c.Cache.L3 = 0, 0, 0, 0
for i := uint32(0); ; i++ {
eax, ebx, ecx, _ := cpuidex(4, i)
cacheType := eax & 15
if cacheType == 0 {
break
}
cacheLevel := (eax >> 5) & 7
coherency := int(ebx&0xfff) + 1
partitions := int((ebx>>12)&0x3ff) + 1
associativity := int((ebx>>22)&0x3ff) + 1
sets := int(ecx) + 1
size := associativity * partitions * coherency * sets
switch cacheLevel {
case 1:
if cacheType == 1 {
// 1 = Data Cache
c.Cache.L1D = size
} else if cacheType == 2 {
// 2 = Instruction Cache
c.Cache.L1I = size
} else {
if c.Cache.L1D < 0 {
c.Cache.L1I = size
}
if c.Cache.L1I < 0 {
c.Cache.L1I = size
}
}
case 2:
c.Cache.L2 = size
case 3:
c.Cache.L3 = size
}
}
case AMD, Hygon:
// Untested.
if maxExtendedFunction() < 0x80000005 {
return
}
_, _, ecx, edx := cpuid(0x80000005)
c.Cache.L1D = int(((ecx >> 24) & 0xFF) * 1024)
c.Cache.L1I = int(((edx >> 24) & 0xFF) * 1024)
if maxExtendedFunction() < 0x80000006 {
return
}
_, _, ecx, _ = cpuid(0x80000006)
c.Cache.L2 = int(((ecx >> 16) & 0xFFFF) * 1024)
// CPUID Fn8000_001D_EAX_x[N:0] Cache Properties
if maxExtendedFunction() < 0x8000001D {
return
}
for i := uint32(0); i < math.MaxUint32; i++ {
eax, ebx, ecx, _ := cpuidex(0x8000001D, i)
level := (eax >> 5) & 7
cacheNumSets := ecx + 1
cacheLineSize := 1 + (ebx & 2047)
cachePhysPartitions := 1 + ((ebx >> 12) & 511)
cacheNumWays := 1 + ((ebx >> 22) & 511)
typ := eax & 15
size := int(cacheNumSets * cacheLineSize * cachePhysPartitions * cacheNumWays)
if typ == 0 {
return
}
switch level {
case 1:
switch typ {
case 1:
// Data cache
c.Cache.L1D = size
case 2:
// Inst cache
c.Cache.L1I = size
default:
if c.Cache.L1D < 0 {
c.Cache.L1I = size
}
if c.Cache.L1I < 0 {
c.Cache.L1I = size
}
}
case 2:
c.Cache.L2 = size
case 3:
c.Cache.L3 = size
}
}
}
}
type SGXEPCSection struct {
BaseAddress uint64
EPCSize uint64
}
type SGXSupport struct {
Available bool
LaunchControl bool
SGX1Supported bool
SGX2Supported bool
MaxEnclaveSizeNot64 int64
MaxEnclaveSize64 int64
EPCSections []SGXEPCSection
}
func hasSGX(available, lc bool) (rval SGXSupport) {
rval.Available = available
if !available {
return
}
rval.LaunchControl = lc
a, _, _, d := cpuidex(0x12, 0)
rval.SGX1Supported = a&0x01 != 0
rval.SGX2Supported = a&0x02 != 0
rval.MaxEnclaveSizeNot64 = 1 << (d & 0xFF) // pow 2
rval.MaxEnclaveSize64 = 1 << ((d >> 8) & 0xFF) // pow 2
rval.EPCSections = make([]SGXEPCSection, 0)
for subleaf := uint32(2); subleaf < 2+8; subleaf++ {
eax, ebx, ecx, edx := cpuidex(0x12, subleaf)
leafType := eax & 0xf
if leafType == 0 {
// Invalid subleaf, stop iterating
break
} else if leafType == 1 {
// EPC Section subleaf
baseAddress := uint64(eax&0xfffff000) + (uint64(ebx&0x000fffff) << 32)
size := uint64(ecx&0xfffff000) + (uint64(edx&0x000fffff) << 32)
section := SGXEPCSection{BaseAddress: baseAddress, EPCSize: size}
rval.EPCSections = append(rval.EPCSections, section)
}
}
return
}
func support() flagSet {
var fs flagSet
mfi := maxFunctionID()
vend, _ := vendorID()
if mfi < 0x1 {
return fs
}
family, model := familyModel()
_, _, c, d := cpuid(1)
fs.setIf((d&(1<<0)) != 0, X87)
fs.setIf((d&(1<<8)) != 0, CMPXCHG8)
fs.setIf((d&(1<<11)) != 0, SCE)
fs.setIf((d&(1<<15)) != 0, CMOV)
fs.setIf((d&(1<<22)) != 0, MMXEXT)
fs.setIf((d&(1<<23)) != 0, MMX)
fs.setIf((d&(1<<24)) != 0, FXSR)
fs.setIf((d&(1<<25)) != 0, FXSROPT)
fs.setIf((d&(1<<25)) != 0, SSE)
fs.setIf((d&(1<<26)) != 0, SSE2)
fs.setIf((c&1) != 0, SSE3)
fs.setIf((c&(1<<5)) != 0, VMX)
fs.setIf((c&0x00000200) != 0, SSSE3)
fs.setIf((c&0x00080000) != 0, SSE4)
fs.setIf((c&0x00100000) != 0, SSE42)
fs.setIf((c&(1<<25)) != 0, AESNI)
fs.setIf((c&(1<<1)) != 0, CLMUL)
fs.setIf(c&(1<<22) != 0, MOVBE)
fs.setIf(c&(1<<23) != 0, POPCNT)
fs.setIf(c&(1<<30) != 0, RDRAND)
// This bit has been reserved by Intel & AMD for use by hypervisors,
// and indicates the presence of a hypervisor.
fs.setIf(c&(1<<31) != 0, HYPERVISOR)
fs.setIf(c&(1<<29) != 0, F16C)
fs.setIf(c&(1<<13) != 0, CX16)
if vend == Intel && (d&(1<<28)) != 0 && mfi >= 4 {
fs.setIf(threadsPerCore() > 1, HTT)
}
if vend == AMD && (d&(1<<28)) != 0 && mfi >= 4 {
fs.setIf(threadsPerCore() > 1, HTT)
}
fs.setIf(c&1<<26 != 0, XSAVE)
fs.setIf(c&1<<27 != 0, OSXSAVE)
// Check XGETBV/XSAVE (26), OXSAVE (27) and AVX (28) bits
const avxCheck = 1<<26 | 1<<27 | 1<<28
if c&avxCheck == avxCheck {
// Check for OS support
eax, _ := xgetbv(0)
if (eax & 0x6) == 0x6 {
fs.set(AVX)
switch vend {
case Intel:
// Older than Haswell.
fs.setIf(family == 6 && model < 60, AVXSLOW)
case AMD:
// Older than Zen 2
fs.setIf(family < 23 || (family == 23 && model < 49), AVXSLOW)
}
}
}
// FMA3 can be used with SSE registers, so no OS support is strictly needed.
// fma3 and OSXSAVE needed.
const fma3Check = 1<<12 | 1<<27
fs.setIf(c&fma3Check == fma3Check, FMA3)
// Check AVX2, AVX2 requires OS support, but BMI1/2 don't.
if mfi >= 7 {
_, ebx, ecx, edx := cpuidex(7, 0)
eax1, _, _, _ := cpuidex(7, 1)
if fs.inSet(AVX) && (ebx&0x00000020) != 0 {
fs.set(AVX2)
}
// CPUID.(EAX=7, ECX=0).EBX
if (ebx & 0x00000008) != 0 {
fs.set(BMI1)
fs.setIf((ebx&0x00000100) != 0, BMI2)
}
fs.setIf(ebx&(1<<2) != 0, SGX)
fs.setIf(ebx&(1<<4) != 0, HLE)
fs.setIf(ebx&(1<<9) != 0, ERMS)
fs.setIf(ebx&(1<<11) != 0, RTM)
fs.setIf(ebx&(1<<14) != 0, MPX)
fs.setIf(ebx&(1<<18) != 0, RDSEED)
fs.setIf(ebx&(1<<19) != 0, ADX)
fs.setIf(ebx&(1<<29) != 0, SHA)
// CPUID.(EAX=7, ECX=0).ECX
fs.setIf(ecx&(1<<5) != 0, WAITPKG)
fs.setIf(ecx&(1<<7) != 0, CETSS)
fs.setIf(ecx&(1<<25) != 0, CLDEMOTE)
fs.setIf(ecx&(1<<27) != 0, MOVDIRI)
fs.setIf(ecx&(1<<28) != 0, MOVDIR64B)
fs.setIf(ecx&(1<<29) != 0, ENQCMD)
fs.setIf(ecx&(1<<30) != 0, SGXLC)
// CPUID.(EAX=7, ECX=0).EDX
fs.setIf(edx&(1<<11) != 0, RTM_ALWAYS_ABORT)
fs.setIf(edx&(1<<14) != 0, SERIALIZE)
fs.setIf(edx&(1<<16) != 0, TSXLDTRK)
fs.setIf(edx&(1<<20) != 0, CETIBT)
fs.setIf(edx&(1<<26) != 0, IBPB)
fs.setIf(edx&(1<<27) != 0, STIBP)
// Only detect AVX-512 features if XGETBV is supported
if c&((1<<26)|(1<<27)) == (1<<26)|(1<<27) {
// Check for OS support
eax, _ := xgetbv(0)
// Verify that XCR0[7:5] = ‘111b’ (OPMASK state, upper 256-bit of ZMM0-ZMM15 and
// ZMM16-ZMM31 state are enabled by OS)
/// and that XCR0[2:1] = ‘11b’ (XMM state and YMM state are enabled by OS).
hasAVX512 := (eax>>5)&7 == 7 && (eax>>1)&3 == 3
if runtime.GOOS == "darwin" {
hasAVX512 = fs.inSet(AVX) && darwinHasAVX512()
}
if hasAVX512 {
fs.setIf(ebx&(1<<16) != 0, AVX512F)
fs.setIf(ebx&(1<<17) != 0, AVX512DQ)
fs.setIf(ebx&(1<<21) != 0, AVX512IFMA)
fs.setIf(ebx&(1<<26) != 0, AVX512PF)
fs.setIf(ebx&(1<<27) != 0, AVX512ER)
fs.setIf(ebx&(1<<28) != 0, AVX512CD)
fs.setIf(ebx&(1<<30) != 0, AVX512BW)
fs.setIf(ebx&(1<<31) != 0, AVX512VL)
// ecx
fs.setIf(ecx&(1<<1) != 0, AVX512VBMI)
fs.setIf(ecx&(1<<6) != 0, AVX512VBMI2)
fs.setIf(ecx&(1<<8) != 0, GFNI)
fs.setIf(ecx&(1<<9) != 0, VAES)
fs.setIf(ecx&(1<<10) != 0, VPCLMULQDQ)
fs.setIf(ecx&(1<<11) != 0, AVX512VNNI)
fs.setIf(ecx&(1<<12) != 0, AVX512BITALG)
fs.setIf(ecx&(1<<14) != 0, AVX512VPOPCNTDQ)
// edx
fs.setIf(edx&(1<<8) != 0, AVX512VP2INTERSECT)
fs.setIf(edx&(1<<22) != 0, AMXBF16)
fs.setIf(edx&(1<<23) != 0, AVX512FP16)
fs.setIf(edx&(1<<24) != 0, AMXTILE)
fs.setIf(edx&(1<<25) != 0, AMXINT8)
// eax1 = CPUID.(EAX=7, ECX=1).EAX
fs.setIf(eax1&(1<<5) != 0, AVX512BF16)
}
}
}
if maxExtendedFunction() >= 0x80000001 {
_, _, c, d := cpuid(0x80000001)
if (c & (1 << 5)) != 0 {
fs.set(LZCNT)
fs.set(POPCNT)
}
fs.setIf((c&(1<<0)) != 0, LAHF)
fs.setIf((c&(1<<10)) != 0, IBS)
fs.setIf((d&(1<<31)) != 0, AMD3DNOW)
fs.setIf((d&(1<<30)) != 0, AMD3DNOWEXT)
fs.setIf((d&(1<<23)) != 0, MMX)
fs.setIf((d&(1<<22)) != 0, MMXEXT)
fs.setIf((c&(1<<6)) != 0, SSE4A)
fs.setIf(d&(1<<20) != 0, NX)
fs.setIf(d&(1<<27) != 0, RDTSCP)
/* XOP and FMA4 use the AVX instruction coding scheme, so they can't be
* used unless the OS has AVX support. */
if fs.inSet(AVX) {
fs.setIf((c&0x00000800) != 0, XOP)
fs.setIf((c&0x00010000) != 0, FMA4)
}
}
if maxExtendedFunction() >= 0x80000007 {
_, b, _, d := cpuid(0x80000007)
fs.setIf((b&(1<<0)) != 0, MCAOVERFLOW)
fs.setIf((b&(1<<1)) != 0, SUCCOR)
fs.setIf((b&(1<<2)) != 0, HWA)
fs.setIf((d&(1<<9)) != 0, CPBOOST)
}
if maxExtendedFunction() >= 0x80000008 {
_, b, _, _ := cpuid(0x80000008)
fs.setIf((b&(1<<9)) != 0, WBNOINVD)
fs.setIf((b&(1<<8)) != 0, MCOMMIT)
fs.setIf((b&(1<<13)) != 0, INT_WBINVD)
fs.setIf((b&(1<<4)) != 0, RDPRU)
fs.setIf((b&(1<<3)) != 0, INVLPGB)
fs.setIf((b&(1<<1)) != 0, MSRIRC)
fs.setIf((b&(1<<0)) != 0, CLZERO)
}
if maxExtendedFunction() >= 0x8000001b && fs.inSet(IBS) {
eax, _, _, _ := cpuid(0x8000001b)
fs.setIf((eax>>0)&1 == 1, IBSFFV)
fs.setIf((eax>>1)&1 == 1, IBSFETCHSAM)
fs.setIf((eax>>2)&1 == 1, IBSOPSAM)
fs.setIf((eax>>3)&1 == 1, IBSRDWROPCNT)
fs.setIf((eax>>4)&1 == 1, IBSOPCNT)
fs.setIf((eax>>5)&1 == 1, IBSBRNTRGT)
fs.setIf((eax>>6)&1 == 1, IBSOPCNTEXT)
fs.setIf((eax>>7)&1 == 1, IBSRIPINVALIDCHK)
}
return fs
}
func valAsString(values ...uint32) []byte {
r := make([]byte, 4*len(values))
for i, v := range values {
dst := r[i*4:]
dst[0] = byte(v & 0xff)
dst[1] = byte((v >> 8) & 0xff)
dst[2] = byte((v >> 16) & 0xff)
dst[3] = byte((v >> 24) & 0xff)
switch {
case dst[0] == 0:
return r[:i*4]
case dst[1] == 0:
return r[:i*4+1]
case dst[2] == 0:
return r[:i*4+2]
case dst[3] == 0:
return r[:i*4+3]
}
}
return r
}