RFR(M): 8181616: FMA Vectorization on x86

[Vladimir Kozlov]

Thank you, Vivek

Why you restrict FMA to AVX?:

-  if (supports_fma() && UseSSE >= 2) {
+  if (supports_fma() && UseAVX > 0) {

Otherwise changes look good.

Thanks,
Vladimir

On 6/5/17 2:42 PM, Deshpande, Vivek R wrote:
> Hi All
>
>
>
> The enhancement generates Vector FMA instructions using SuperWord Analysis for X86.
>
> We observed upto 6x gain on Skylake and KNL using 512 bit Vector FMA instructions using FMA API operating on independent arrays.
>
> Webrev:
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> http://cr.openjdk.java.net/~vdeshpande/8181616/webrev.00/
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> I have also updated the JBS entry.
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> https://bugs.openjdk.java.net/browse/JDK-8181616
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> Would you please review and sponsor it.
>
>
>
> Regards,
>
> Vivek
>
>
>