RFR: 8278411: Implement UseHeavyMonitors consistently, s390 port

[Martin Doerr]

On Mon, 15 May 2023 08:25:19 GMT, Amit Kumar <amitkumar at openjdk.org> wrote:

> This PR make s390x to adapt the changes done in [JDK-8276901](https://bugs.openjdk.org/browse/JDK-8276901) OR implements UseHeavyMonitors. 
> 
> [JDK-8291555](https://bugs.openjdk.org/browse/JDK-8291555) still needs Porting effort. As for `LM_LIGHTWEIGHT` locking mode, code is Unimplemented.

Please check my findings.

src/hotspot/cpu/s390/macroAssembler_s390.cpp line 3193:

> 3191:   } else {
> 3192:     // Set NE to indicate 'failure' -> take slow-path
> 3193:     z_ltgr(oop, oop);

I think `z_bru(done);` is missing, here.

src/hotspot/cpu/s390/macroAssembler_s390.cpp line 3269:

> 3267:   } else {
> 3268:     // Set NE to indicate 'failure' -> take slow-path
> 3269:     z_ltgr(oop, oop);

Same, here.

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PR Review: https://git.openjdk.org/jdk/pull/13978#pullrequestreview-1426489612
PR Review Comment: https://git.openjdk.org/jdk/pull/13978#discussion_r1193791851
PR Review Comment: https://git.openjdk.org/jdk/pull/13978#discussion_r1193792804