[lworld] RFR: 8271282: [lworld] C2 compilation fails with "bad AD file"

[Tobias Hartmann]

This is a variant of mainline issue [JDK-8269775](https://bugs.openjdk.java.net/browse/JDK-8269775). It only showed up now because it requires AVX-512 VLBW capable machines. This PR is cherry-picking the fixes for [JDK-8269580](https://bugs.openjdk.java.net/browse/JDK-8269580) and [JDK-8269775](https://bugs.openjdk.java.net/browse/JDK-8269775) and adjusts them to Valhalla specific changes.

Best regards,
Tobias

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Commit messages:
 - 8271282: [lworld] C2 compilation fails with "bad AD file"

Changes: https://git.openjdk.java.net/valhalla/pull/497/files
 Webrev: https://webrevs.openjdk.java.net/?repo=valhalla&pr=497&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8271282
  Stats: 31 lines in 2 files changed: 5 ins; 12 del; 14 mod
  Patch: https://git.openjdk.java.net/valhalla/pull/497.diff
  Fetch: git fetch https://git.openjdk.java.net/valhalla pull/497/head:pull/497

PR: https://git.openjdk.java.net/valhalla/pull/497