RFR: 8287205: generate_cont_thaw generates dead code after jump to exception handler [v2]

[Richard Reingruber]

> This fix avoids generating unreachable instructions after the jump to the exception handler in `generate_cont_thaw()`
> 
> Testing:
> 
> jtreg:test/hotspot/jtreg:hotspot_loom
> jtreg:test/jdk:jdk_loom
> 
> On linux x86_64 and aarch64.
> 
> On aarch64 the test `jdk/java/lang/management/ThreadMXBean/VirtualThreadDeadlocks.java` had a timeout. The aaarch64 machine I used is very slow. This might have caused the timeout.

Richard Reingruber has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains three additional commits since the last revision:

 - Merge branch 'master' into 8287205_remove_dead_code_from_generate_cont_thaw
 - Merge branch 'master' into 8287205_remove_dead_code_from_generate_cont_thaw
 - Remove dead code from generate_cont_thaw

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/8863/files
  - new: https://git.openjdk.java.net/jdk/pull/8863/files/9489400f..c82674a7

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=8863&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=8863&range=00-01

  Stats: 81814 lines in 880 files changed: 30489 ins; 44462 del; 6863 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8863.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8863/head:pull/8863

PR: https://git.openjdk.java.net/jdk/pull/8863