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diff --git a/vendor/github.com/klauspost/cpuid/v2/README.md b/vendor/github.com/klauspost/cpuid/v2/README.md new file mode 100644 index 00000000..465f4b77 --- /dev/null +++ b/vendor/github.com/klauspost/cpuid/v2/README.md @@ -0,0 +1,137 @@ +# cpuid +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/i386) and ARM (ARM64) is supported, and no external C (cgo) code is used, which should make the library very easy to use. + +You can access the CPU information by accessing the shared CPU variable of the cpuid library. + +Package home: https://github.com/klauspost/cpuid + +[](https://pkg.go.dev/github.com/klauspost/cpuid/v2) +[![Build Status][3]][4] + +[3]: https://travis-ci.org/klauspost/cpuid.svg?branch=master +[4]: https://travis-ci.org/klauspost/cpuid + +## installing + +`go get -u github.com/klauspost/cpuid/v2` using modules. + +Drop `v2` for others. + +## example + +```Go +package main + +import ( + "fmt" + "strings" + + . "github.com/klauspost/cpuid/v2" +) + +func main() { + // Print basic CPU information: + fmt.Println("Name:", CPU.BrandName) + fmt.Println("PhysicalCores:", CPU.PhysicalCores) + fmt.Println("ThreadsPerCore:", CPU.ThreadsPerCore) + fmt.Println("LogicalCores:", CPU.LogicalCores) + fmt.Println("Family", CPU.Family, "Model:", CPU.Model, "Vendor ID:", CPU.VendorID) + fmt.Println("Features:", fmt.Sprintf(strings.Join(CPU.FeatureSet(), ","))) + fmt.Println("Cacheline bytes:", CPU.CacheLine) + fmt.Println("L1 Data Cache:", CPU.Cache.L1D, "bytes") + fmt.Println("L1 Instruction Cache:", CPU.Cache.L1D, "bytes") + fmt.Println("L2 Cache:", CPU.Cache.L2, "bytes") + fmt.Println("L3 Cache:", CPU.Cache.L3, "bytes") + fmt.Println("Frequency", CPU.Hz, "hz") + + // Test if we have these specific features: + if CPU.Supports(SSE, SSE2) { + fmt.Println("We have Streaming SIMD 2 Extensions") + } +} +``` + +Sample output: +``` +>go run main.go +Name: AMD Ryzen 9 3950X 16-Core Processor +PhysicalCores: 16 +ThreadsPerCore: 2 +LogicalCores: 32 +Family 23 Model: 113 Vendor ID: AMD +Features: ADX,AESNI,AVX,AVX2,BMI1,BMI2,CLMUL,CMOV,CX16,F16C,FMA3,HTT,HYPERVISOR,LZCNT,MMX,MMXEXT,NX,POPCNT,RDRAND,RDSEED,RDTSCP,SHA,SSE,SSE2,SSE3,SSE4,SSE42,SSE4A,SSSE3 +Cacheline bytes: 64 +L1 Data Cache: 32768 bytes +L1 Instruction Cache: 32768 bytes +L2 Cache: 524288 bytes +L3 Cache: 16777216 bytes +Frequency 0 hz +We have Streaming SIMD 2 Extensions +``` + +# usage + +The `cpuid.CPU` provides access to CPU features. Use `cpuid.CPU.Supports()` to check for CPU features. +A faster `cpuid.CPU.Has()` is provided which will usually be inlined by the gc compiler. + +Note that for some cpu/os combinations some features will not be detected. +`amd64` has rather good support and should work reliably on all platforms. + +Note that hypervisors may not pass through all CPU features. + +## arm64 feature detection + +Not all operating systems provide ARM features directly +and there is no safe way to do so for the rest. + +Currently `arm64/linux` and `arm64/freebsd` should be quite reliable. +`arm64/darwin` adds features expected from the M1 processor, but a lot remains undetected. + +A `DetectARM()` can be used if you are able to control your deployment, +it will detect CPU features, but may crash if the OS doesn't intercept the calls. +A `-cpu.arm` flag for detecting unsafe ARM features can be added. See below. + +Note that currently only features are detected on ARM, +no additional information is currently available. + +## flags + +It is possible to add flags that affects cpu detection. + +For this the `Flags()` command is provided. + +This must be called *before* `flag.Parse()` AND after the flags have been parsed `Detect()` must be called. + +This means that any detection used in `init()` functions will not contain these flags. + +Example: + +```Go +package main + +import ( + "flag" + "fmt" + "strings" + + "github.com/klauspost/cpuid/v2" +) + +func main() { + cpuid.Flags() + flag.Parse() + cpuid.Detect() + + // Test if we have these specific features: + if cpuid.CPU.Supports(cpuid.SSE, cpuid.SSE2) { + fmt.Println("We have Streaming SIMD 2 Extensions") + } +} +``` + +# license + +This code is published under an MIT license. See LICENSE file for more information. |