[PATCH] 8217561 : X86: Add floating-point Math.min/max intrinsics

[B. Blaser]

Hi Sandhya,

On Fri, 1 Feb 2019 at 22:58, Viswanathan, Sandhya
<sandhya.viswanathan at intel.com> wrote:
>
> Hi All,
>
> Please find below the updated patch from Jatin:
>
> http://cr.openjdk.java.net/~sviswanathan/Jatin/8217561/webrev.01/
>
> This patch fixes the issue reported by Nils.

Could you clarify the problem and its solution?
I don't see any USE_KILL you mentioned earlier, or maybe the test case
wasn't correct as Jatin said previously?

> The compiler jtreg tests on Haswell and SKX pass successfully.

The fix also affects x86_32.ad, could you confirm that at least
test-tier1 is successful with these older families too?

> It shows about 25% gain on Haswell desktop and about 75% on SKX server.

Great!

> Changing the maxps to maxss and cmpps to cmpss didn’t show any performance difference.

Conceptually, I dislike useless computation even if well parallelized
which might increase the processor's temperature and reduce
performance on long runs (but this is a personal opinion).

Regarding copyright headers, I note that the year hasn't been updated
to 2019 on some of them and on the test file:

http://cr.openjdk.java.net/~sviswanathan/Jatin/8217561/webrev.01/test/hotspot/jtreg/compiler/intrinsics/math/TestFpMinMaxIntrinsics.java.html

I read:

3  * Copyright (c) 2018, Arm Limited. All rights reserved.

Is 'Arm Limitied' intended?

Thanks,
Bernard

> Best Regards,
> Sandhya