RFR: 8288047: Accelerate Poly1305 on x86_64 using AVX512 instructions [v20]

Wed Nov 16 23:19:19 UTC 2022

On Wed, 16 Nov 2022 23:08:16 GMT, Vladimir Ivanov <vlivanov at openjdk.org> wrote:

>> src/hotspot/cpu/x86/stubGenerator_x86_64_poly.cpp line 917:
>> 
>>> 915:   // Cleanup
>>> 916:   __ vpxorq(xmm0, xmm0, xmm0, Assembler::AVX_512bit);
>>> 917:   __ vpxorq(xmm1, xmm1, xmm1, Assembler::AVX_512bit);
>> 
>> You could use T0, T1 in place of xmm0, xmm1 here.
>
> Or simply switch to `vzeroall` for `xmm0` - `xmm15`.

ah.. I remember thinking about doing that.. `vzeroall` isnt encoded yet and I figured since I already have to do the xmm16-29, might as well do them all.. should I add that instruction too?

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PR: https://git.openjdk.org/jdk/pull/10582