RFR: 8332537: C2: High memory usage reported for compiler/loopopts/superword/TestAlignVectorFuzzer.java

[Emanuel Peter]

This bug was a regression of:
[JDK-8324517](https://bugs.openjdk.org/browse/JDK-8324517); C2: crash in compiled code because of dependency on removed range check CastIIs

That change was backed out with:
[JDK-8332829](https://bugs.openjdk.org/browse/JDK-8332829): [BACKOUT] C2: crash in compiled code because of dependency on removed range check CastIIs

I `git revert` ed the BACKOUT change:
[JDK-8332829](https://bugs.openjdk.org/browse/JDK-8332829): [BACKOUT] C2: crash in compiled code because of dependency on removed range check CastIIs

And only then this reproduced (not on master, only with Roland's CastII regression code):
`~/Documents/jtreg/bin/jtreg -va -s -jdk:/oracle-work/jdk-fork2/build/linux-x64-debug/jdk -javaoptions:"-Djdk.test.lib.random.seed=3249981201344669190" -J-Djavatest.maxOutputSize=10000000 /oracle-work/jdk-fork2/open/test/hotspot/jtreg/compiler/loopopts/superword/TestAlignVectorFuzzer.java`

Now that we know that it is a regression of a backed-out change, we can enable the MemLimit check again.

Also the stack-traces were related to CastII code, and looked very similar to those in another duplicate:
[JDK-8332765](https://bugs.openjdk.org/browse/JDK-8332765): Test compiler/loopopts/superword/TestAlignVectorFuzzer.java still times out after JDK-8327978

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Commit messages:
 - JDK-8332537

Changes: https://git.openjdk.org/jdk/pull/19580/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=19580&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8332537
  Stats: 4 lines in 1 file changed: 0 ins; 4 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/19580.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19580/head:pull/19580

PR: https://git.openjdk.org/jdk/pull/19580