public inbox for
 help / color / mirror / Atom feed
From: Jerry DeLisle <>
To: Thomas Koenig <>,
	"" <>,
	gcc-patches <>
Subject: Re: [patch, libfortran] AMD-specific versions of library matmul
Date: Thu, 25 May 2017 14:11:00 -0000	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

On 05/25/2017 03:45 AM, Thomas Koenig wrote:
> Hello world,
> the attached patch speeds up the library version of matmul for AMD chips
> by selecting AVX128 instructions and, depending on which instructions
> are supported, either FMA3 (aka FMA) or FMA4.
> Jerry tested this on his AMD systems, and found a speedup vs. the
> current code of around 10%.
> I have been unable to test this on a Ryzen system (the new compile farm
> machines won't accept my login yet).  From the benchmarks I have read,
> this method should also work fairly well on a Ryzen.
> So, OK for trunk?

Yes, OK.  Maybe test Ryzen first?

I just confirmed access to the Ryzen machines so I plan to get set up and test 

Time to start looking under the hood.

cat /proc/cpuinfo gives for flags:

flags		: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 
clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm 
constant_tsc rep_good nopl nonstop_tsc extd_apicid aperfmperf eagerfpu pni 
pclmulqdq monitor ssse3 fma cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c 
rdrand lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 
3dnowprefetch osvw skinit wdt tce topoext perfctr_core perfctr_nb bpext 
perfctr_l2 mwaitx hw_pstate vmmcall fsgsbase bmi1 avx2 smep bmi2 rdseed adx smap 
clflushopt sha_ni xsaveopt xsavec xgetbv1 xsaves clzero irperf arat npt lbrv 
svm_lock nrip_save tsc_scale vmcb_clean flushbyasid decodeassists pausefilter 
pfthreshold avic overflow_recov succor smca

  parent reply	other threads:[~2017-05-25 14:06 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <>
2017-05-25 11:19 ` Fwd: " Thomas Koenig
2017-05-25 14:11 ` Jerry DeLisle [this message]
2017-05-25 14:52   ` Thomas Koenig
2017-05-25 17:58 ` Janne Blomqvist
2017-05-25 20:31   ` Jerry DeLisle
2017-05-25 23:44     ` Thomas Koenig
2017-05-26  5:41       ` Jerry DeLisle
2017-05-26  6:21         ` Andrew Pinski
2017-05-26 15:33           ` Bill Seurer

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \ \ \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).