RFR(S) JDK-8205528: Base64 Encode Algorithm using AVX512 Instructions

Wed Jun 27 20:21:33 UTC 2018

Okay. I started new testing.

Thanks,
Vladimir

On 6/27/18 12:58 PM, Kamath, Smita wrote:
> Hi Vladimir,
> 
> Please find the updated webrev.
> 
> Bug link: https://bugs.openjdk.java.net/browse/JDK-8205528
> Webrev link : http://cr.openjdk.java.net/~srukmannagar/Base64/webrev.01/
> 
> Thanks,
> Smita
> 
> 
> 
> -----Original Message-----
> From: Vladimir Kozlov [mailto:vladimir.kozlov at oracle.com]
> Sent: Tuesday, June 26, 2018 12:54 PM
> To: Kamath, Smita <smita.kamath at intel.com>
> Cc: hotspot compiler <hotspot-compiler-dev at openjdk.java.net>
> Subject: Re: RFR(S) JDK-8205528: Base64 Encode Algorithm using AVX512 Instructions
> 
> Hit build failure on Windows:
> 
> jib >
> t:/workspace/open/src/hotspot/cpu/x86/stubGenerator_x86_64.cpp(4556):
> error C2024: 'alignas' attribute applies to variables, data members and tag types only jib >
> t:/workspace/open/src/hotspot/cpu/x86/stubGenerator_x86_64.cpp(4595):
> error C2024: 'alignas' attribute applies to variables, data members and tag types only jib >
> t:/workspace/open/src/hotspot/cpu/x86/stubGenerator_x86_64.cpp(4634):
> error C2024: 'alignas' attribute applies to variables, data members and tag types only jib >
> t:/workspace/open/src/hotspot/cpu/x86/stubGenerator_x86_64.cpp(4649):
> error C2024: 'alignas' attribute applies to variables, data members and tag types only jib >
> t:/workspace/open/src/hotspot/cpu/x86/stubGenerator_x86_64.cpp(4664):
> error C2024: 'alignas' attribute applies to variables, data members and tag types only jib >
> t:/workspace/open/src/hotspot/cpu/x86/stubGenerator_x86_64.cpp(4679):
> error C2024: 'alignas' attribute applies to variables, data members and tag types only jib >
> t:/workspace/open/src/hotspot/cpu/x86/stubGenerator_x86_64.cpp(4693):
> error C2024: 'alignas' attribute applies to variables, data members and tag types only jib > lib/CompileJvm.gmk:149: recipe for target '/cygdrive/t/workspace/build/windows-x64/hotspot/variant-server/libjvm/objs/stubGenerator_x86_64.obj'
> failed
> 
> Vladimir
> 
> On 6/26/18 11:48 AM, Vladimir Kozlov wrote:
>> Yes, this looks good to me. Let me test it.
>>
>> Thanks,
>> Vladimir
>>
>> On 6/25/18 10:25 PM, Kamath, Smita wrote:
>>> Hi Vladimir,
>>>
>>> Please find the updated webrev link.
>>>
>>> Webrev Link:
>>> http://cr.openjdk.java.net/~srukmannagar/Base64/webrev.00/
>>> Bug link: https://bugs.openjdk.java.net/browse/JDK-8205528
>>>
>>> Please let me know if you have additional questions.
>>>
>>> Thanks and Regards,
>>> Smita
>>>
>>> -----Original Message-----
>>> From: Vladimir Kozlov [mailto:vladimir.kozlov at oracle.com]
>>> Sent: Monday, June 25, 2018 10:48 AM
>>> To: Kamath, Smita <smita.kamath at intel.com>
>>> Cc: hotspot compiler <hotspot-compiler-dev at openjdk.java.net>;
>>> core-libs-dev at openjdk.java.net; Paul Sandoz <paul.sandoz at oracle.com>
>>> Subject: Re: RFR(S) JDK-8205528: Base64 Encode Algorithm using AVX512
>>> Instructions
>>>
>>> I forgot to reply to your answers.
>>>
>>> On 6/22/18 2:49 PM, Kamath, Smita wrote:
>>>> Hi Vladimir,
>>>>
>>>> Please see my answers to your questions as below:
>>>>
>>>> 1) One question so: why you have own copy of base64 charsets and not
>>>> using one in library:
>>>> I am using vpgatherdd instruction to fetch multiple values from
>>>> base64 array in a single instruction with a vector index. Vpgatherdd
>>>> instruction works on 32 bit array and so I need to define base64
>>>> charset in a 32 bit array. I have given reference to gather
>>>> instruction below.
>>>
>>> As was discussed in an other e-mail lets keep your copy.
>>>
>>>>
>>>> 2) Some indents in new and old Assembler::emit_operand() are off. In
>>>> new Assembler::emit_operand() is better use } else { instead of
>>>> 'return' in one branch.
>>>> I'll make the necessary changes and send an updated webrev.
>>>>
>>>> 3) This is first time I see that XMM register can be used for index
>>>> in address. Is it true? Can you point to Intel's document which
>>>> describes it.
>>>> I am using vpgatherdd instruction which requires index vector with
>>>> scale. It uses VSIB addressing where the index register is a zmm
>>>> register.
>>>> Please refer to reference manual, volume 2c, page 2211:
>>>> https://software.intel.com/sites/default/files/managed/39/c5/325462-
>>>> sd m-vol-1-2abcd-3abcd.pdf Also see, section 2.3.12, page 524 for
>>>> VSIB memory addressing information.
>>>
>>> Got it. Thanks for document reference.
>>>
>>>>
>>>> 4)  Please, add tests to
>>>> test/hotspot/jtreg/compiler/intrinsics/base64 (may be similar to sha
>>>> or AES in compiler/codegen/aes) to make sure that all flags,
>>>> intrinsic is used and it produces correct result.
>>>> I will add test cases as per your suggestion.
>>>
>>> Thanks,
>>> Vladimir
>>>
>>>>
>>>> Please let me know if you have additional questions.
>>>>
>>>> Thanks,
>>>> Smita
>>>>
>>>> -----Original Message-----
>>>> From: Vladimir Kozlov [mailto:vladimir.kozlov at oracle.com]
>>>> Sent: Friday, June 22, 2018 12:29 PM
>>>> To: Kamath, Smita <smita.kamath at intel.com>
>>>> Cc: hotspot compiler <hotspot-compiler-dev at openjdk.java.net>
>>>> Subject: Re: RFR(S) JDK-8205528: Base64 Encode Algorithm using
>>>> AVX512 Instructions
>>>>
>>>> Hi Smita,
>>>>
>>>> I CCing to Libs to review code changes in Base64.java.
>>>>
>>>> Looks like you changed all need place to implement intrinsic.
>>>> One question so: why you have own copy of base64 charsets and not
>>>> using one in library:
>>>>
>>>>              private int encode0(byte[] src, int off, int end, byte[]
>>>> dst) {
>>>>                  char[] base64 = isURL ? toBase64URL : toBase64;
>>>>
>>>> Some indents in new and old Assembler::emit_operand() are off.
>>>>
>>>> In new Assembler::emit_operand() is better use } else { instead of
>>>> 'return' in one branch.
>>>>
>>>> This is first time I see that XMM register can be used for index in
>>>> address. Is it true? Can you point to Intel's document which
>>>> describes it.
>>>>
>>>> What testing you did?
>>>>
>>>> Please, add tests to test/hotspot/jtreg/compiler/intrinsics/base64
>>>> (may be similar to sha or AES in compiler/codegen/aes) to make sure
>>>> that all flags, intrinsic is used and it produces correct result.
>>>>
>>>> I know there is test/jdk/java/util/Base64/ tests but they may not
>>>> trigger intrinsic usage. But you can use them as starting point for
>>>> new tests.
>>>>
>>>> Thanks,
>>>> Vladimir
>>>>
>>>> On 6/22/18 11:47 AM, Kamath, Smita wrote:
>>>>> Hi Vladimir,
>>>>>
>>>>> I'd like to contribute an optimization for Base64 Encoding
>>>>> Algorithm using AVX512 Instructions. This optimization shows 1.5x
>>>>> improvement on
>>>>> x86_64 platform(SKL).
>>>>>
>>>>> Link to Bug: https://bugs.openjdk.java.net/browse/JDK-8205528
>>>>>
>>>>> Link to webrev:
>>>>> http://cr.openjdk.java.net/~vdeshpande/Base64/webrev.00/
>>>>>
>>>>> For testing the implementation, I have run tests under
>>>>> test/jdk/java/util/Base64/ and also ran
>>>>> test/jdk/com/sun/jndi/ldap/Base64Test.java
>>>>>
>>>>> I have also run jtreg.
>>>>>
>>>>> Please review and let me know if you have any comments.
>>>>>
>>>>> Thanks and Regards,
>>>>>
>>>>> Smita
>>>>>