Software Tuning, Performance Optimization & Platform Monitoring
Discussion regarding monitoring and software tuning methodologies, Performance Monitoring Unit (PMU) of Intel microprocessors, and platform updating.
Announcements
The Intel sign-in experience has changed to support enhanced security controls. If you sign in, click here for more information.

what FPU pipe does VBROADCASTSD go down?

perfwise
Beginner
202 Views
What pipe does VBROADCASTSD go down? I looked in the latency/throughput section of the intel optguide and it doesn't list this information. Thanks
perfwise
0 Kudos
4 Replies
perfwise
Beginner
202 Views
I haven't heard which pipe it goes down but from my assembly performance it surely isn't pipe 0 or 1 where the 256-bit add and mul units are. Thought I'd let people know..

perfwise
Bernard
Black Belt
202 Views

>>>I haven't heard which pipe it goes down but from my assembly performance it surely isn't pipe 0 or 1>>>

Do you mean execution unit's Port?

perfwise
Beginner
202 Views

Yes, but it's a moot point now.  I was tuning my dgemm for SB and IB and noticed some "replication" instructions utilized the same pipe as the + or *, can't remember off the top of my head.  vbroadcastsd doesn't and is preferrable for this purpose.  

perfwise

Bernard
Black Belt
202 Views
I suppose that store/load Ports 2 and 3 are executing VBROADCASTSD instruction.
Reply