RFR: 8331658: secondary_super_cache does not scale well: C1

[Andrew Haley]

This is the C1 version of [JDK-8180450](https://bugs.openjdk.org/browse/JDK-8180450).

The new logic in this PR is as simple as I can make it. It is a somewhat-simplified version of the C2 change in [JDK-8180450](https://bugs.openjdk.org/browse/JDK-8180450). In order to reduce risk I haven't touched the existing slow subtype stub.
The register allocation logic in the existing code is pretty gnarly, and I have no desire to break anything at this point in the release cycle, so I have allocated just one register more than te existing code.

Performance is pretty good. Before and after:

x64, AMD 2950X, 8 cores:


Benchmark                                   Mode  Cnt   Score   Error  Units
SecondarySuperCacheHits.test                avgt    5   0.959 ± 0.091  ns/op
SecondarySuperCacheInterContention.test     avgt    5  42.931 ± 6.951  ns/op
SecondarySuperCacheInterContention.test:t1  avgt    5  42.397 ± 7.708  ns/op
SecondarySuperCacheInterContention.test:t2  avgt    5  43.466 ± 8.238  ns/op
SecondarySuperCacheIntraContention.test     avgt    5  74.660 ± 0.127  ns/op

SecondarySuperCacheHits.test                avgt    5  1.480 ± 0.077  ns/op
SecondarySuperCacheInterContention.test     avgt    5  1.461 ± 0.063  ns/op
SecondarySuperCacheInterContention.test:t1  avgt    5  1.767 ± 0.078  ns/op
SecondarySuperCacheInterContention.test:t2  avgt    5  1.155 ± 0.052  ns/op
SecondarySuperCacheIntraContention.test     avgt    5  1.421 ± 0.002  ns/op

AArch64, Mac M3, 8 cores:


Benchmark                     Mode  Cnt  Score   Error  Units
SecondarySuperCacheHits.test                avgt    5    0.835 ±  0.021  ns/op
SecondarySuperCacheInterContention.test     avgt    5   74.078 ± 18.095  ns/op
SecondarySuperCacheInterContention.test:t1  avgt    5   81.863 ± 42.492  ns/op
SecondarySuperCacheInterContention.test:t2  avgt    5   66.293 ± 11.254  ns/op
SecondarySuperCacheIntraContention.test     avgt    5  335.563 ±  6.171  ns/op

SecondarySuperCacheHits.test                avgt    5  1.212 ±  0.004  ns/op
SecondarySuperCacheInterContention.test     avgt    5  0.871 ±  0.002  ns/op
SecondarySuperCacheInterContention.test:t1  avgt    5  0.626 ±  0.003  ns/op
SecondarySuperCacheInterContention.test:t2  avgt    5  1.115 ±  0.006  ns/op
SecondarySuperCacheIntraContention.test     avgt    5  0.696 ±  0.001  ns/op



The first test, `SecondarySuperCacheHits`, showns a small regression. It's the "happy path" which simply checks the same subclass again and again in a loop, in a single thread. I suspect that, as with the C2 experiments we did, this will never be noticeable. All the other tests, though, show a huge improvement, so performance is a lot more predictable.

This patch only affects `checkcast` and `instanceof`. The performance of `Class::isInstance()` isn't affected because it's not intrinsified in C1, and neither is any of the logic for arraycopy intrinsics.

After the next release is done, I'd like to do a big cleanup and simplification of subtype checking, which should include the still-missing parts of C1 and the interpreter and make everything much more maintainable.

Finally, this patch doesn't greatly help with tiered compilation because the subtype checking runtime is greatly affected by profile counter updates. It's really all about pure C1, which seems to be popular in some short-lived cloud applications.

-------------

Commit messages:
 - JDK-8331341: secondary_super_cache does not scale well: C1 and interpreter
 - JDK-8331341: secondary_super_cache does not scale well: C1 and interpreter
 - Merge branch 'clean' into C1-hash-supers
 - JDK-8331341: secondary_super_cache does not scale well: C1 and interpreter
 - JDK-8331341: secondary_super_cache does not scale well: C1 and interpreter
 - JDK-8331341: secondary_super_cache does not scale well: C1 and interpreter
 - JDK-8331341: secondary_super_cache does not scale well: C1 and interpreter
 - Test
 - Merge branch 'C1-hash-supers' of https://github.com/theRealAph/jdk into C1-hash-supers
 - Merge branch 'C1-hash-supers' of https://github.com/theRealAph/jdk into C1-hash-supers
 - ... and 95 more: https://git.openjdk.org/jdk/compare/235ba9a7...8c05732c

Changes: https://git.openjdk.org/jdk/pull/19426/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19426&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8331658
  Stats: 232 lines in 9 files changed: 205 ins; 3 del; 24 mod
  Patch: https://git.openjdk.org/jdk/pull/19426.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19426/head:pull/19426

PR: https://git.openjdk.org/jdk/pull/19426