Integrated: 8325541: C2 SuperWord: refactor filter / split

[Emanuel Peter]

On Fri, 9 Feb 2024 10:06:59 GMT, Emanuel Peter <epeter at openjdk.org> wrote:

> A few filter / split methods are currently bunched together. We should peal them apart so that moving / changing things becomes easier in the future.
> 
> 
> combine_packs -> refactored into:
>   combine_packs (now really only combines)
>   split_packs_for_max_vector_size
>   filter_packs_for_power_of_2_size
>   filter_packs_for_mutual_independence
> 
> filter_packs -> refactored into:
>   filter_packs_for_implemented
>   filter_packs_for_profitable
> 
> 
> Since we have so many "filter" passes, I created a dedicated `SuperWord::filter_packs` method, that takes a `FilterPredicate` lambda. This also allows me now to systematically debug dump any packs that are rejected .
> 
> I also took the liberty to enforce a new invariant between passes: there cannot be any `nullptr` in the packlist.
> Before the "filter" passes just set some packs to `nullptr`. I now shift all surviving packs down, and truncate the packlist.

This pull request has now been integrated.

Changeset: 6dfa7f39
Author:    Emanuel Peter <epeter at openjdk.org>
URL:       https://git.openjdk.org/jdk/commit/6dfa7f39411169c1d4c1aeb3b5d635ad0d625f9b
Stats:     291 lines in 2 files changed: 121 ins; 71 del; 99 mod

8325541: C2 SuperWord: refactor filter / split

Reviewed-by: chagedorn, kvn

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

PR: https://git.openjdk.org/jdk/pull/17785