On Wed, 21 Aug 2024 16:42:44 GMT, Jatin Bhateja <jbhat...@openjdk.org> wrote:

>> Hi All,
>> 
>> As per the discussion on panama-dev mailing list[1], patch adds the support 
>> for following new two vector permutation APIs.
>> 
>> 
>> Declaration:-
>>     Vector<E>.selectFrom(Vector<E> v1, Vector<E> v2)
>> 
>> 
>> Semantics:-
>>     Using index values stored in the lanes of "this" vector, assemble the 
>> values stored in first (v1) and second (v2) vector arguments. Thus, first 
>> and second vector serves as a table, whose elements are selected based on 
>> index value vector. API is applicable to all integral and floating-point 
>> types.  The result of this operation is semantically equivalent to 
>> expression v1.rearrange(this.toShuffle(), v2). Values held in index vector 
>> lanes must lie within valid two vector index range [0, 2*VLEN) else an 
>> IndexOutOfBoundException is thrown.  
>> 
>> Summary of changes:
>> -  Java side implementation of new selectFrom API.
>> -  C2 compiler IR and inline expander changes.
>> -  In absence of direct two vector permutation instruction in target ISA, a 
>> lowering transformation dismantles new IR into constituent IR supported by 
>> target platforms. 
>> -  Optimized x86 backend implementation for AVX512 and legacy target.
>> -  Function tests covering new API.
>> 
>> JMH micro included with this patch shows around 10-15x gain over existing 
>> rearrange API :-
>> Test System: Intel(R) Xeon(R) Platinum 8480+ [ Sapphire Rapids Server]
>> 
>> 
>>   Benchmark                                     (size)   Mode  Cnt      
>> Score   Error   Units
>> SelectFromBenchmark.rearrangeFromByteVector     1024  thrpt    2   2041.762  
>>         ops/ms
>> SelectFromBenchmark.rearrangeFromByteVector     2048  thrpt    2   1028.550  
>>         ops/ms
>> SelectFromBenchmark.rearrangeFromIntVector      1024  thrpt    2    962.605  
>>         ops/ms
>> SelectFromBenchmark.rearrangeFromIntVector      2048  thrpt    2    479.004  
>>         ops/ms
>> SelectFromBenchmark.rearrangeFromLongVector     1024  thrpt    2    359.758  
>>         ops/ms
>> SelectFromBenchmark.rearrangeFromLongVector     2048  thrpt    2    178.192  
>>         ops/ms
>> SelectFromBenchmark.rearrangeFromShortVector    1024  thrpt    2   1463.459  
>>         ops/ms
>> SelectFromBenchmark.rearrangeFromShortVector    2048  thrpt    2    727.556  
>>         ops/ms
>> SelectFromBenchmark.selectFromByteVector        1024  thrpt    2  33254.830  
>>         ops/ms
>> SelectFromBenchmark.selectFromByteVector        2048  thrpt    2  17313.174  
>>         ops/ms
>> SelectFromBenchmark.selectFromIntVector         1024  thrpt    2  10756.804  
>>         ops/ms
>> S...
>
> Jatin Bhateja has updated the pull request incrementally with one additional 
> commit since the last revision:
> 
>   Pass explicit wrap argument to selectFrom API with default value set to 
> true.

Hi @rose00 , @sviswa7 , @PaulSandoz , 
As suggested, now passing explicit 'wrap' argument to new selectFrom API.

Following are the performance number of modified JMH micro included with the 
patch.



Baseline:-
Benchmark                                      (size)   Mode  Cnt     Score   
Error   Units
SelectFromBenchmark.rearrangeFromByteVector     4096  thrpt    2  5849.771      
    ops/ms
SelectFromBenchmark.rearrangeFromDoubleVector   4096  thrpt    2   430.712      
    ops/ms
SelectFromBenchmark.rearrangeFromFloatVector    4096  thrpt    2   942.737      
    ops/ms
SelectFromBenchmark.rearrangeFromIntVector      4096  thrpt    2  1057.695      
    ops/ms
SelectFromBenchmark.rearrangeFromLongVector     4096  thrpt    2   616.360      
    ops/ms
SelectFromBenchmark.rearrangeFromShortVector    4096  thrpt    2  2146.465      
    ops/ms

With Patch:-
Benchmark                                   (size)   Mode  Cnt     Score   
Error   Units
SelectFromBenchmark.selectFromByteVector        4096  thrpt    2  9543.775      
    ops/ms
SelectFromBenchmark.selectFromDoubleVector      4096  thrpt    2   558.195      
    ops/ms
SelectFromBenchmark.selectFromFloatVector       4096  thrpt    2  1325.059      
    ops/ms
SelectFromBenchmark.selectFromIntVector         4096  thrpt    2  1418.748      
    ops/ms
SelectFromBenchmark.selectFromLongVector        4096  thrpt    2   687.231      
    ops/ms
SelectFromBenchmark.selectFromShortVector       4096  thrpt    2  4782.395      
    ops/ms


With WIP wrap index acceleration PR#20634:
Benchmark                                      (size)   Mode  Cnt     Score   
Error   Units
SelectFromBenchmark.rearrangeFromByteVector     4096  thrpt    2  7602.645      
    ops/ms
SelectFromBenchmark.rearrangeFromDoubleVector   4096  thrpt    2   441.684      
    ops/ms
SelectFromBenchmark.rearrangeFromFloatVector    4096  thrpt    2   926.112      
    ops/ms
SelectFromBenchmark.rearrangeFromIntVector      4096  thrpt    2  1061.695      
    ops/ms
SelectFromBenchmark.rearrangeFromLongVector     4096  thrpt    2   644.058      
    ops/ms
SelectFromBenchmark.rearrangeFromShortVector    4096  thrpt    2  2777.735      
    ops/ms

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

PR Comment: https://git.openjdk.org/jdk/pull/20508#issuecomment-2302541724

Reply via email to