RFR: 8292289: [vectorapi] Improve the implementation of VectorTestNode [v2]

[Quan Anh Mai]

On Thu, 18 Aug 2022 02:24:16 GMT, Xiaohong Gong <xgong at openjdk.org> wrote:

>> Quan Anh Mai has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains 17 commits:
>> 
>>  - redo aarch
>>  - Merge branch 'master' into improveVTest
>>  - delete aarch64 vector files
>>  - copyright
>>  - fix condition
>>  - fix alltrue
>>  - change VectorTest to subclass Cmp
>>  - add test
>>  - fix aarch build
>>  - remove dst in x86.ad
>>  - ... and 7 more: https://git.openjdk.org/jdk/compare/0d96546a...cac9948e
>
> src/hotspot/cpu/aarch64/matcher_aarch64.hpp line 167:
> 
>> 165: 
>> 166:   // Some architecture needs a helper to check for alltrue vector
>> 167:   static bool vectortest_need_second_argument(bool is_alltrue, bool is_predicate) {
> 
> I think we can get the predicate feature in the backend (i.e.  `Matcher::has_predicated_vectors()`), and we do not need the argument here?

On AVX3 the availability of predicated vectors does not ensure that every species of vector mask would be translated into predicated vector. To be more specific, although AVX512F returns true for `Matcher::has_predicated_vectors()`, byte and short vector masks required AVX512BW to be translated into predicated vectors and vector masks of < 512-bit species require AVX512VL.

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PR: https://git.openjdk.org/jdk/pull/9855