[aarch64-port-dev ] RFR(S): 8087341: C2 doesn't optimize redundant memory operations with G1

[Andrew Haley]

On 12/02/16 11:25, Andrew Dinn wrote:
> Not quite. Roland's change without the AArch64 patch triggered an assert
> during CAS generation when the expected subgraph was not found.

Hmm.  Can this code not be changed to fail quietly, with no change
to the code?  That's what optimizations generally do.

> Also, the current code is not built to expect whatever barrier
> Shenandoah might insert. It ought to fall into much the same case as G1
> and CMS + CondCardMark (depending upon how the GC barriers are
> generated). However, a check which folds Shenandoah into the same bucket
> as those two still needs explicitly wiring in.

Sure.

Andrew.