[jdk25u] RFR: 8369946: Bytecode rewriting causes Java heap corruption on PPC

[Martin Doerr]

This pull request contains a backport of commit [6bf3581b](https://github.com/openjdk/jdk/commit/6bf3581bbacc2ed8f6411d23a5ab332376c53c87) from the [openjdk/jdk](https://git.openjdk.org/jdk) repository.

The commit being backported was authored by Martin Doerr on 22 Oct 2025 and was reviewed by Richard Reingruber and David Briemann.

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Commit messages:
 - Backport 6bf3581bbacc2ed8f6411d23a5ab332376c53c87

Changes: https://git.openjdk.org/jdk25u/pull/331/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk25u&pr=331&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8369946
  Stats: 36 lines in 3 files changed: 12 ins; 4 del; 20 mod
  Patch: https://git.openjdk.org/jdk25u/pull/331.diff
  Fetch: git fetch https://git.openjdk.org/jdk25u.git pull/331/head:pull/331

PR: https://git.openjdk.org/jdk25u/pull/331