Add FEAT_CMH support

[ricbal02]

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Hi all,

This is a PR to propose the addition of new intrinsics required as part of FEAT_CMH.

Quality Level: ALP

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[Wilco1]

floating point??? Let's stick to scalar integer only. I don't believe there is any use of FP variants anyway.

[Lukacma]

I think the idea was to be consistent with the store intrinsic. Or is there a reason to have different type support between the 2 ?

[Wilco1]

Since it can't be done on compare&exchange loops, you'd have to check that for all architectures where CMH is allowed that FP atomics are a must-have and not optional. It's complex.

[Wilco1]

supports -> support

[Wilco1]

"store" is not accurate here, it does a RMW.

[Wilco1]

Same here "to be stored"

[Wilco1]

.