Count16BitElements() intrinsic for SVE

[a74nh]

Extracted from #94765

For now, this is based off both #94529 and #94791

All the new code starts from 3cb75c5

For now it emits an MRS instruction. This needs updating to use an SVE CNTH, however, the codegen parts need adding alongside. Will wait until I can use the tool.

JitDumping the test program, I see the MRS

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Issue Details

---

Extracted from #94765

For now, this is based off both #94529 and #94791

For now it emits an MRS instruction. This needs updating to use an SVE CNTH, however, the codegen parts need adding alongside. Will wait until I can use the tool.

JitDumping the test program, I see the MRS

Author:	a74nh
Assignees:	-
Labels:	area-CodeGen-coreclr, new-api-needs-documentation, community-contribution
Milestone:	-

[jkotas]

Should this be _Sve?

[a74nh]

This needs rebasing. But still can't progress into until skeleton library files are committed.

[ghost]

Draft Pull Request was automatically closed for 30 days of inactivity. Please let us know if you'd like to reopen it.