internal/cpu,golang.org/x/sys/cpu: support windows/arm64

[qmuntal]

This is a tracking issue to add support for Windows ARM64 to internal/cpu and golang.org/x/sys/cpu. They currently don't set any supported cpu flag on this platform, even when Windows provides an API to prove if a given feature is supported by the current computer: IsProcessorFeaturePresent.

This is a mapping of Go feature flags to IsProcessorFeaturePresent flags (note that some flags are taken from the published Windows headers, as learn.microsoft.com is not really up-to-date).

• HasAES => PF_ARM_V8_CRYPTO_INSTRUCTIONS_AVAILABLE
• HasPMULL => PF_ARM_V8_CRYPTO_INSTRUCTIONS_AVAILABLE
• HasSHA1 => PF_ARM_V8_CRYPTO_INSTRUCTIONS_AVAILABLE
• HasSHA2 => PF_ARM_V8_CRYPTO_INSTRUCTIONS_AVAILABLE
• HasSHA3 => PF_ARM_SHA3_INSTRUCTIONS_AVAILABLE
• HasCRC32 => PF_ARM_V8_CRC32_INSTRUCTIONS_AVAILABLE
• HasSHA512 => PF_ARM_SHA512_INSTRUCTIONS_AVAILABLE
• HasATOMICS => PF_ARM_V81_ATOMIC_INSTRUCTIONS_AVAILABLE
• HasASIMDDP => PF_ARM_V82_DP_INSTRUCTIONS_AVAILABLE
• HasASIMDRDM => PF_ARM_V82_DP_INSTRUCTIONS_AVAILABLE
• HasLRCPC => PF_ARM_V83_LRCPC_INSTRUCTIONS_AVAILABLE
• HasSM3=> PF_ARM_V83_LRCPC_INSTRUCTIONS_AVAILABLE
• HasSVE => PF_ARM_SVE_INSTRUCTIONS_AVAILABLE
• HasSVE2 => PF_ARM_SVE2_INSTRUCTIONS_AVAILABLE
• HasJSCVT => PF_ARM_V83_JSCVT_INSTRUCTIONS_AVAILABLE

@golang/windows

[gabyhelp]

Related Issues

• x/sys/cpu: add support for ARM #33508
• x/sys/cpu: add support for darwin/arm64 #43046
• x/sys/cpu: add support for detecting AVX-512 #41288 (closed)
• internal/cpu: ARM feature detection #26630 (closed)
• x/sys/cpu: No flag for SVE2 detection #66952 (closed)
• all: better support for cpu feature detection #19739 (closed)
• x/sys/cpu: add ARM64 and PPC64 support #25185 (closed)

_{(Emoji vote if this was helpful or unhelpful; more detailed feedback welcome in this discussion.)}

[mknyszek]

CC @golang/windows @golang/runtime

[gopherbot]

Change https://go.dev/cl/740500 mentions this issue: windows: add IsProcessorFeaturePresent and processor feature consts

[alexbrainman]

@qmuntal

I sent https://go-review.googlesource.com/c/sys/+/740500 that adds IsProcessorFeaturePresent to golang.org/x/sys/windows package.

I will make changes togolang.org/x/sys/cpu next.

Please, let me know, if I should stop.

Thank you.

Alex

[qmuntal]

Please continue the good work! I had this on my TODO list, but still haven't started 😸 .

[alexbrainman]

@qmuntal

You did not say what to do about HasASIMD and HasFP. They are currently set to true on windows/arm64

https://github.com/golang/sys/blob/d25a7aaff8c2b056b2059fd7065afe1d4132e082/cpu/cpu_arm64.go#L58-L63

Should I set both HasASIMD and HasFP to true or false? Should I use IsProcessorFeaturePresent for them?

Thank you.

Alex

[gopherbot]

Change https://go.dev/cl/740880 mentions this issue: cpu: use IsProcessorFeaturePresent to calculate ARM64 on windows