RFR: 8350111: [PPC] AsyncGetCallTrace crashes when called while handling SIGTRAP [v2]

[Richard Reingruber]

> With this change `JavaThread::pd_get_top_frame_for_profiling()` fails if the current thread is found to be `_thread_in_Java` but the CodeCache does not contain its pc.
> 
> This will prevent crashes as described by the JBS item.
> 
> The fix might be too conservative for situations where a thread doen't change its thread state when calling native code, e.g. using the Foreign Function & Memory API. The difficulty finding a less defensive fix is that one must detect if a valid pc can be found in the caller's ABI before constructing that frame.
> 
> Testing:
> 
> * DaCapo Tomcat with async-profiler on a fastdebug build.
> * Tier 1-4 of hotspot and jdk on the main platforms and also on Linux/PPC64le and AIX.

Richard Reingruber has updated the pull request incrementally with two additional commits since the last revision:

 - A frame isn't safe_for_sender if sender_pc() returns null
 - Revert first fix
   
   This reverts commit c4b81e2dc5a854efde8475d09b33b8f53dde987d.

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/23641/files
  - new: https://git.openjdk.org/jdk/pull/23641/files/c4b81e2d..9a2eedc5

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=23641&range=01
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=23641&range=00-01

  Stats: 26 lines in 3 files changed: 9 ins; 12 del; 5 mod
  Patch: https://git.openjdk.org/jdk/pull/23641.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/23641/head:pull/23641

PR: https://git.openjdk.org/jdk/pull/23641