RFR: 8339386: Assertion on AIX - original PC must be in the main code section of the compiled method

[Martin Doerr]

We should make sure to read the `sender_pc` only once to make it signal safe (e.g. using `volatile`). Now, we can check if it is a deopt PC and if so, if the original PC is within the nmethod.
In case of interpreter frame on top of compiled deoptimized frame we need to use the unextendedSP (2nd commit).

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Commit messages:
 - Handle interpreter frame on top of compiled deoptimized frame.
 - 8339386: Assertion on AIX - original PC must be in the main code section of the compiled method

Changes: https://git.openjdk.org/jdk/pull/21189/files
  Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=21189&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8339386
  Stats: 12 lines in 1 file changed: 9 ins; 0 del; 3 mod
  Patch: https://git.openjdk.org/jdk/pull/21189.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/21189/head:pull/21189

PR: https://git.openjdk.org/jdk/pull/21189