RFR: 8325252: C2 SuperWord: refactor the packset [v2]

[Emanuel Peter]

On Mon, 25 Mar 2024 09:39:08 GMT, Christian Hagedorn <chagedorn at openjdk.org> wrote:

>> Emanuel Peter has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Apply Christian's suggestions
>>   
>>   Co-authored-by: Christian Hagedorn <christian.hagedorn at oracle.com>
>
> src/hotspot/share/opto/superword.cpp line 1304:
> 
>> 1302: 
>> 1303: // Estimate the savings from executing s1 and s2 as a pack
>> 1304: int SuperWord::estimate_cost_savings_when_packing_pair(const Node* s1, const Node* s2) const {
> 
> Nit: Should we add a `as` or `to`?
> Suggestion:
> 
> int SuperWord::estimate_cost_savings_when_packing_as_pair(const Node* s1, const Node* s2) const {

done

> src/hotspot/share/opto/superword.cpp line 1338:
> 
>> 1336:     for (DUIterator_Fast kmax, k = s2->fast_outs(kmax); k < kmax; k++) {
>> 1337:       if (use2 == s2->fast_out(k)) {
>> 1338:         ct++;
> 
> Maybe add the following as a visual aid?
> 
>  s1      s2
>   |      |
> [use1, use2]

Sure

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

PR Review Comment: https://git.openjdk.org/jdk/pull/18276#discussion_r1537498286
PR Review Comment: https://git.openjdk.org/jdk/pull/18276#discussion_r1537502548