RFR: 8323582: C2 SuperWord AlignVector: misaligned vector memory access with unaligned native memory

[Emanuel Peter]

On Tue, 25 Feb 2025 00:34:14 GMT, Vladimir Kozlov <kvn at openjdk.org> wrote:

> > But if we do not optimize the slow path loop, then we would get performance regressions in aliasing cases because we have no unrolling for them any more.
> 
> Okay, we are back to our previous conversation - we will wait your aliasing-analysis runtime-checks implementation and do performance runs to see if "slow" path affects performance.
> 
> Okay.

Sounds good, we will revisit and write more benchmarks there.

> 
> PS: "slow" path implies that it is not taking frequently and it should not affect general performance of application.

For me "slow" just means less optimized, because some assumption does not hold. The "fast" path is faster, because it has more assumptions and can optimize more (i.e. vectorize in this case, or vectorize more instructions). Do you have a better name than "fast/slow"?

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PR Comment: https://git.openjdk.org/jdk/pull/22016#issuecomment-2680885496