RFR: 8254263: Remove special_runtime_exit_condition() check from ~ThreadInVMForHandshake() [v2]

[Patricio Chilano Mateo]

> Hi all,
> 
> Please review the following patch that removes the call to handle_special_runtime_exit_condition() in
> ~ThreadInVMForHandshake(). This check was added by 8223572 to prevent a JavaThread that was suspended while trying to
> process a handshake to transition back to java without noticing it was suspended. Since 8238761, a JavaThread executing
> HandshakeState::process_by_self() will never become safe. It comes from an unsafe state and remains unsafe, so it
> cannot be suspended during that time. Removing this check also removes one of the reasons
> SafepointMechanism::process_if_requested() is recursive (the other one remains SafepointSynchronize::block()). Tested
> in mach5, tiers 1-7.  Thanks, Patricio

Patricio Chilano Mateo has updated the pull request incrementally with one additional commit since the last revision:

  added async exception check

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

Changes:
  - all: https://git.openjdk.java.net/jdk/pull/577/files
  - new: https://git.openjdk.java.net/jdk/pull/577/files/d442af8c..d1222d98

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=577&range=01
 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=577&range=00-01

  Stats: 15 lines in 1 file changed: 3 ins; 0 del; 12 mod
  Patch: https://git.openjdk.java.net/jdk/pull/577.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/577/head:pull/577

PR: https://git.openjdk.java.net/jdk/pull/577