RFR: 8267125: AES Galois CounterMode (GCM) interleaved implementation using AVX512 + VAES instructions [v4]

[Vladimir Kozlov]

On Wed, 14 Jul 2021 21:02:01 GMT, Smita Kamath <svkamath at openjdk.org> wrote:

>> I would like to submit AES-GCM optimization for x86_64 architectures supporting AVX3+VAES (Evex encoded AES). This optimization interleaves AES and GHASH operations.
>> Performance gain of ~1.5x - 2x for message sizes 8k and above.
>
> Smita Kamath has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Updated AES-GCM intrinsic to match latest Java Code

First, you need review from Tony for Java side changes.

Second, you need to extend tests in `test/hotspot/jtreg/compiler/codegen/aes/` to cover this implementation.

And, third, I think we need to put this on hold until the issue of big intrinsics stubs generation effect on startup is solved. See discussion in https://bugs.openjdk.java.net/browse/JDK-8270323


-   code_size1 = 20000 LP64_ONLY(+10000),         // simply increase if too small (assembler will crash if too small)
-   code_size2 = 35300 LP64_ONLY(+25000)          // simply increase if too small (assembler will crash if too small)
+   code_size1 = 20000 LP64_ONLY(+12000),         // simply increase if too small (assembler will crash if too small)
+   code_size2 = 35300 LP64_ONLY(+37000)          // simply increase if too small (assembler will crash if too small)


@sviswa7 please, note these changes too for our discussion.

src/hotspot/cpu/x86/stubGenerator_x86_64.cpp line 7644:

> 7642:     }
> 7643:     if (UseAESIntrinsics) {
> 7644:       if (VM_Version::supports_avx512_vaes() &&  VM_Version::supports_avx512vl() && VM_Version::supports_avx512dq()) {

Why duplicate already existing checks? Move code there and add comment for which intrinsic code is generated.

src/hotspot/cpu/x86/stubRoutines_x86.hpp line 36:

> 34: enum platform_dependent_constants {
> 35:   code_size1 = 20000 LP64_ONLY(+12000),         // simply increase if too small (assembler will crash if too small)
> 36:   code_size2 = 35300 LP64_ONLY(+37000)          // simply increase if too small (assembler will crash if too small)

This is almost 50% increase !!!

src/hotspot/share/jvmci/vmStructs_jvmci.cpp line 333:

> 331:   static_field(StubRoutines,                _bigIntegerRightShiftWorker,                      address)                               \
> 332:   static_field(StubRoutines,                _bigIntegerLeftShiftWorker,                       address)                               \
> 333:   static_field(StubRoutines,                _galoisCounterMode_AESCrypt,                      address)                               \

Move up to other AESCrypt lines.

src/hotspot/share/opto/escape.cpp line 1111:

> 1109:                   strcmp(call->as_CallLeaf()->_name, "bigIntegerLeftShiftWorker") == 0 ||
> 1110:                   strcmp(call->as_CallLeaf()->_name, "vectorizedMismatch") == 0 ||
> 1111:                   strcmp(call->as_CallLeaf()->_name, "galoisCounterMode_AESCrypt") == 0 ||

Please, move new line where other AEScrypt methods listed.

src/hotspot/share/runtime/stubRoutines.cpp line 130:

> 128: address StubRoutines::_base64_encodeBlock                  = NULL;
> 129: address StubRoutines::_base64_decodeBlock                  = NULL;
> 130: address StubRoutines::_galoisCounterMode_AESCrypt          = NULL;

Move up few lines

src/hotspot/share/runtime/stubRoutines.hpp line 212:

> 210:   static address _base64_encodeBlock;
> 211:   static address _base64_decodeBlock;
> 212:   static address _galoisCounterMode_AESCrypt;

Move up few lines

src/hotspot/share/runtime/vmStructs.cpp line 592:

> 590:      static_field(StubRoutines,                _unsafe_arraycopy,                             address)                               \
> 591:      static_field(StubRoutines,                _generic_arraycopy,                            address)                               \
> 592:      static_field(StubRoutines,                _galoisCounterMode_AESCrypt,                   address)                               \

Move up to other AESCrypt declarations.

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

Changes requested by kvn (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/4019