RFR: 8288669: compiler/vectorapi/VectorFPtoIntCastTest.java still fails with "IRViolationException: There were one or multiple IR rule failures."

[Christian Hagedorn]

IR matching fails when run with `-XX:-TieredCompilation` because we don't have enough profiling information. There is an RFE ([JDK-8276547](https://bugs.openjdk.org/browse/JDK-8276547)) that should change the fixed default warm-up into a compilation policy based warm-up to prevent such test failures in the future. The fix for this test is to just increase the default warm-up for now.

Testing:
- tier1-4 flags for VectorFPtoIntCastTest.java
- repeated runs with tier3 flags (includes `-XX:-TieredCompilation`)

Thanks,
Christian

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Commit messages:
 - 8288669: compiler/vectorapi/VectorFPtoIntCastTest.java still fails with "IRViolationException: There were one or multiple IR rule failures."

Changes: https://git.openjdk.org/jdk/pull/9259/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=9259&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8288669
  Stats: 11 lines in 1 file changed: 3 ins; 0 del; 8 mod
  Patch: https://git.openjdk.org/jdk/pull/9259.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/9259/head:pull/9259

PR: https://git.openjdk.org/jdk/pull/9259