RFR: 8302681: [IR Framework] Only allow cpuFeatures from a verified list

[Emanuel Peter]

On Mon, 20 Feb 2023 15:11:21 GMT, Emanuel Peter <epeter at openjdk.org> wrote:

> Wrongly typed cpuFeatures can lead to an IR rule being ignored.
> Example: https://github.com/openjdk/jdk/pull/12601 [JDK-8302668](https://bugs.openjdk.org/browse/JDK-8302668)
> 
> We should have a list of verified cpuFeatures, and assert if one is used that is not in that list. That way, typos and bad copies can be avoided, and we make sure the tests run when intended.
> 
> I verified the `intel` cpuFeatures by hand on my laptop. And for `asimd` and `sve` I asked @tobiasholenstein and @nick-arm .
> 
> `sve1` seems to have been a typo, and I am changing it to `sve`.
> 
> Note: cpu-features can be displayed like this: `./java -Xlog:os+cpu --version`
> 
> On my machine, I get:
> 
> cmov, fxsr, ht, mmx, 3dnowpref, sse, sse2, sse3, ssse3, sse4.1, sse4.2, popcnt, lzcnt, tsc, tscinvbit, avx, avx2, aes, erms, clmul, bmi1, bmi2, adx, avx512f, avx512dq, avx512cd, avx512bw, avx512vl, sha, fma, vzeroupper, avx512_vpopcntdq, avx512_vpclmulqdq, avx512_vaes, avx512_vnni, clflush, clflushopt, clwb, avx512_vbmi2, avx512_vbmi, rdtscp, rdpid, fsrm, gfni, avx512_bitalg, f16c, pku, ospke, cet_ibt, cet_ss, avx512_ifma
> 
> 
> @nick-arm got this on one of his machines:
> 
> fp, asimd, evtstrm, aes, pmull, sha1, sha256, crc32, lse, dcpop, sha3, sha512, sve, paca
> 
> 
> @tobiasholenstein got this:
> 
> fp, asimd, aes, pmull, sha1, sha256, crc32, lse, sha3, sha512

@fg1417 Could you tell me if `sve` and `sve1` are actually cpu-featues that any hardware ever has? Especially `sve1` seems suspicious to me.

**Update** `sve` is a real cpu-feature, and `sve1` seems to have been a typo.

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PR: https://git.openjdk.org/jdk/pull/12669