[jdk19] RFR: 8288128: S390X: Fix crashes after JDK-8284161 (Virtual Threads)

[Martin Doerr]

On Tue, 5 Jul 2022 17:38:32 GMT, Tyler Steele <tsteele at openjdk.org> wrote:

> This PR adapts the changes to the PPC port from JDK-8286446 and JDK-8288105 to s390 in order to fix the crashes preventing a successful `make images`.
> 
> In addition, the following (minor) changes were made to the changesets above:
> - Change two instances of `own_abi()->lr` to `own_abi()->return_pc` (frame_s390.cpp:235,247)
> - Remove alignment assertion from `frame::setup` (frame_s390.inline.hpp:73)
> - Remove original_pc assertion from `frame::patch_pc` (frame_s390.cpp:251)
> - Add continuations_enabled guard to `generate_phase1` (stubGenerator_s390.cpp:2937)

Looks good! Thanks for porting it to s390!

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Marked as reviewed by mdoerr (Reviewer).

PR: https://git.openjdk.org/jdk19/pull/110