RFR: 8295872: [PPC64] JfrGetCallTrace: Need pc == nullptr check before frame constructor

[Martin Doerr]

On Fri, 28 Oct 2022 06:57:26 GMT, Matthias Baesken <mbaesken at openjdk.org> wrote:

> JavaThread::pd_last_frame() is now unused on the ppc64 platforms, is that correct ? Should there be some guarantee or assertion in JavaThread::pd_last_frame() before return frame(sp, pc); too ?

Good question. `pd_last_frame()` is now only called by `last_frame()` on PPC64. I'll think about if the acquire barrier is still needed there or if the addition from JDK-8290004 could get reverted. Note that `pc != nullptr` is already asserted in the frame constructor.

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

PR: https://git.openjdk.org/jdk/pull/10846