RFR: 8331126: [s390x] secondary_super_cache does not scale well [v8]

[Amit Kumar]

On Fri, 28 Jun 2024 09:02:29 GMT, Andrew Haley <aph at openjdk.org> wrote:

>> Amit Kumar has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains ten commits:
>> 
>>  - Merge branch 'master' into ssc_v0
>>  - comments from martin
>>  - add2reg -> z_la
>>  - comments from Lutz
>>  - Update src/hotspot/cpu/s390/macroAssembler_s390.cpp
>>  - rename: r_scratch to r_result in repne_scan method
>>  - Update src/hotspot/cpu/s390/macroAssembler_s390.cpp
>>  - Removes unused Labels & makes comment more sensible
>>  - [s390x] secondary super cache port
>
> src/hotspot/cpu/s390/macroAssembler_s390.cpp line 3329:
> 
>> 3327:   // NOTE: please load 0 only in r_result, for now lookup_secondary_supers_table sets r_result to 0
>> 3328:   // clear_reg(r_result, true /* whole_reg */, false /* set_cc */); // let's hope that search will be a success
>> 3329:   z_cghi(r_result, 0);
> 
> I don't understand this comment. What does "for now" mean?

At present, lookup_secondary_supers_table updates r_result just in case it changes in future.

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

PR Review Comment: https://git.openjdk.org/jdk/pull/19544#discussion_r1658393165