RFR: 8331558: AArch64: optimize integer remainder [v3]

[Jin Guojie]

On Wed, 8 May 2024 02:45:13 GMT, Eric Liu <eliu at openjdk.org> wrote:

>> Jin Guojie has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Applicable platforms expanded to the entire neoverse family
>>   
>>   Even on the V series (V1 and V2), both sdiv/udiv and msub instructions are executed in M0 unit (Integer multi cycle). It should benefit the V series as well.
>
> src/hotspot/cpu/aarch64/vm_version_aarch64.hpp line 181:
> 
>> 179:               (model_is(CPU_MODEL_NEOVERSE_V1) || model_is(CPU_MODEL_NEOVERSE_V2));
>> 180:   }
>> 181: 
> 
> Not in used.

In this commit, is_neoverse_n_series() is removed.

https://github.com/openjdk/jdk/pull/19093/commits/9cbff8319ad808276665339f1313e373a81b392d

However, is_neoverse_v_series() is called in vm_version_aarch64.cpp, 

  if (is_neoverse_v_series()) {
    if (FLAG_IS_DEFAULT(UseCryptoPmullForCRC32)) {
      FLAG_SET_DEFAULT(UseCryptoPmullForCRC32, true);
    }
  }

so this function remains unchanged.

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PR Review Comment: https://git.openjdk.org/jdk/pull/19093#discussion_r1594918558