RFR: 8327978: C2 SuperWord: Fix compilation time regression in dependency graph traversal after JDK-8325651 [v2]

[Emanuel Peter]

On Wed, 3 Apr 2024 22:36:16 GMT, Vladimir Kozlov <kvn at openjdk.org> wrote:

>> Emanuel Peter has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   For Vladimir: check is_Store first
>
> src/hotspot/share/opto/superword.cpp line 3125:
> 
>> 3123:         for (DUIterator_Fast imax, i = mem->fast_outs(imax); i < imax; i++) {
>> 3124:           Node* mem_use = mem->fast_out(i);
>> 3125:           if (_vloop.in_bb(mem_use) && !visited.test(bb_idx(mem_use)) && mem_use->is_Store()) {
> 
> `mem_use->is_Store()` check is cheap and should be first. It will also help to skip other checks for Load node.

Sure, I can do that :)

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PR Review Comment: https://git.openjdk.org/jdk/pull/18532#discussion_r1550926982