Alder Lake and AVX-512

By: Geoff Langdale (geoff.langdale.delete@this.gmail.com), July 12, 2020 7:18 pm
Room: Moderated Discussions
People like shuffles because they are a poor man's table lookup in SIMD. You can do a lot with shuffles. PSHUFB, particularly, is also insanely cheap. Quite a bit of the uses of SSE4.2 (the string stuff, that is) are pre-obsoleted by clever uses of PSHUFB.

OK, I'm going to have to mostly disappoint you on your hoped-for fight. I am a AVX-512 enthusiast, but I like SVE/SVE2 (in theory) too.

You see, you regard these ISAs as a angry customer or a disappointed boss: "why is this so shit?" This is reasonable, but years ago (back when I stopped being a RISC Zealot and Embraced The Suck of weird x86 everywhere) I've stopped thinking this way.

You're a customer shopping at Ikea and you're pissed that you can't find a perfectly reasonable piece of office furniture that should exist. By contrast, I'm a browser at a rummage sale - that weird sideboard with 3 unicorn heads poking out of it looks like just the thing to raise my monitor to the right level. I'm pleasantly surprised when anything works at all, and enjoy the mental challenge of dealing with a butt-ugly and thoroughly non-orthogonal ISA.

Having *TWO* of these fucking things to deal with - if we wind up with a situation with AVX-512 and SVE2 - will be even more fun.

So yes, I've been taken to the 'put my fist through the monitor' stage repeatedly with the design of everything from SSE all the way to AVX-512 (and beyond; I got to put my fist through the monitor occasionally at things that didn't even exist yet, in a way that made no difference to anyone, as no-one cares what some obscure dude from Australia thinks). A lot of stuff makes no sense. Bytes and often 16-bit values are treated as second-class citizens. Frequently you can choose between "signed op on this particular size" or "unsigned op on this other size" but not both. Multiplies particularly are an insane lucky dip. Various noisy people got to have single instructions that are their whole goddamn inner loop for some video codec no-one uses anymore, while I can't have fucking byte-level shifts?

AVX-512 adds and removes problems - it clears up some orthogonality, but other things are still pointlessly stupid (you can't do masked logic ops on anything smaller than a 32-bit value, IIRC).

However, if you are like me, these are opportunities to have fun. For example, I was tickled to find that GFNI can reconstruct most of the missing byte shift/rotate operations (though sadly not for dynamic quantities per-lane).

Now the ARM side of the fence - NEON has traditionally been more orthogonal - overall I like it better. Almost everything that you can do for one size element you can do at another - no more "we did this for 32 bits and 16 bits, then got sleepy and went to bed". However, there are a few instructions that I sorely miss (PMOVMSKB, most notably, to extract the high bits back into GPR land). And historically, NEON implementations was incredibly slow at getting stuff from SIMD units back to GPRs in general (which wasn't a huge focus for them).

The thing that gets me about SVE/SVE2 - which honestly I don't know all that much about - is simple:

Where are the implementations?

They announced SVE years ago. They don't even bloody publicly *roadmap* the thing much less ship it anywhere aside from Fujitsu. I can't really get behind you praising them for "handling low end implementations better than Intel" because they haven't really DONE any implementations aside from one weirdo supercomputer. I think we've all seen *that* particular trick before.

So I'll get excited when ARM gets their shit together and releases at least 2 mainstream implementations of SVE (one bigger, one smaller) and we'll see how well it actually works. Until then, the 'S' in SVE is a marketing claim. People can yell until they are blue in the face about how great something is based on the architecture manual, but I'd rather play with hardware - or failing that, at least see the throughput/latency numbers for an actual implementation. Until then, to me, it's just a pile of on-paper nonsense.

I'm writing this on a laptop that runs the whole gamut of AVX-512 (up to and including GFNI, VBMI2, etc - lots of cool tricks possible). I've had the laptop for months. It's real hardware. I'm not going to lose my shit about how much better the SVE/SVE2 design is on paper until someone troubles themselves to release it in a real mainstream implementation.

There are green shoots for SVE (not SVE2, at least not that I've seen so far). I'm not saying it's bullshit. I wouldn't be surprised to see it this year. I'll be happy to learn about it when it really tips up. But I'm not going to judge the whole 'scalability' thing as a success until it actually scales, and I'm not going to judge it as a success for a high-performance mainstream implementation until I see that implementation in working order.

Also, if past experience has been anything to go on, there will be plenty of weird/disgusting bits (whether in terms of available ISA or in terms of what operations are actually fast and what aren't) to have to work around on the SVE/SVE2 side of the fence too. So more fun for the 'rummage sale' mentalities...

Geoff.

Linus Torvalds (torvalds.delete@this.linux-foundation.org) on July 12, 2020 11:35 am wrote:
> Geoff Langdale (geoff.langdale.delete@this.gmail.com) on July 11, 2020 11:45 pm wrote:
> >
> > It's not clear to me whether you view AVX2 in the same light, btw - what do you think
> > of AVX2 circa 2020?
>
> No honestly, I'm not a huge fan of AVX2 either. But then. wasn't a huge fan of MMX or the original AVX.
> And no, before you ask, it's not like I hold up the original i387 FPU as some shining example either ;)
>
> None of them are what you would call anything like remotely clean, and none of them were ever designed to be
> sanely extensible, nor were any of them ever designed to be able to be used independently of each other.
>
> You get the worst of both worlds.
>
> Just for an example of that "independently" issue: there are a ton of loads that could have used
> the original MMX instructions, but because it perturbs the state of the previous FPU side, you
> couldn't actually do that. It was an all-or-nothing change, and it hurt people. Badly.
>
> It's not even about the mixed code case (although that famously happened too), it's about the "occasional use".
> There are lots of situations where you might want to have a small helper, and it would make sense to use a
> single vector register or two, and you do a couple of ops, and you save/restore only those registers.
>
> And that fundamentally has never worked in the Intel world, because of the state dirtying.
> Using MME/SSE dirties the FPU state even if you're careful and try to save/restore
> things, so you were supposed to do a full state save and init and restore. So any
> "I could use this in a tiny" way helper functions were completely doomed.
>
> (And by "completely doomed", I mean that some people did it anyway, and it mostly worked, I think).
>
> Now, that said, do I hate MMX/SSE/AVX/AVX2 with the same burning passion
> as AVX512? No. Because there's a big difference between them.
>
> MMX/SSE was a first-attempt (plus fixes). The i387 was a particularly nasty thing
> to be compatible with anyway, it's entirely understandable why it was done the way
> it was done. In hindsight, maybe it could have been done better, but a "in hindsight"
> argument is always complete BS. So that's not a valid argument. MMX/SSE was fine.
>
> AVX/AVX2 were reasonable cleanups and honestly, I don't think 256 bits is a huge pain even as a baseline.
> And Intel has been good about keeping AVX always there. Afaik, new CPU's really have gotten AVX reliably.
> So it hasn't been a fragmentation issue, and while I think it has the same state dirtying issue ("helper
> function using MMX instructions and saves/restores the instructions it modifies will be clearing upper
> bits in AVX registers and trashing state"), I think it was a fairly reasonable extension.
>
> So again, AVX/AVX2 was fine. Was it "lovely"? No. But I think it's a reasonable baseline.
>
> So what's different with AVX512?
>
> One fundamental difference is that fragmentation issue. It came up before AVX512 was even out,
> with the failed multi-core Knights atoms having a completely different versions. But it's really
> been obvious lately, with even today, in CPU's being sold, it being a "marketing feature".
>
> But the other - and to me really annoying - fundamental issue is "by
> now, you should have damn well have learnt from your mistakes".
>
> Here, look at the real competition for Intel and x86 long-term: ARM. They had an equally disgusting and horrendously
> bad FPU situation originally. Yes, their FPU situation was differently bad from the i387, but the whole soft-FP
> vs VFP vs random other implementations was arguably worse than Intel ever had, even if at the time, you would
> find the usual ARM fanbois that made excuses for just how horrendous the situation was.
>
> But then ARM got their act together, and NEON happened. I'd say that was roughly the equivalent to
> SSE, because I'll call the original mess of nasty shit comparable to the nofp/i387/IBM-mis-wiring-the-exception-pin/MMX
> era. The timing may not line up, but with NEON, ARM at least had gotten rid of their messy lack of
> standards, and I think it's fair to compare it to Intel and SSE conceptually.
>
> So ARM did SVE, and I'll call that their AVX/AVX2. But now you see signs of differences.
> Part of it is just the name. "S" for "Scalable". ARM is starting to do something
> interesting and fundamentally different from what AVX was for Intel.
>
> And then ARM designed SVE2, and again, let's see how it actually plays out in real life,
> but I think it has the potential to be their "AVX512 done right". And they designed
> it to have a reasonable downgrade/upgrade path, to be extensible, to do that masking
> and memory accesses etc that is so important for compilers to auto-parallelize.
>
> Honestly, if I were into HPC and vectorization, I'd be all in on the ARM bandwagon.
>
> As it happens, I'm not into HPC and vectorization, and it's possible that exactly because I'm not
> into it, I'm missing why SVE2 has some horrible problems. And I realize that AVX512 does some things
> that a very very very small minority of people care deeply about (I don't know why, but some people
> really love the shuffle instructions and will put up with absolutely anything if they get them).
>
> So just as a bystander, I'm looking at AVX512, and I'm looking
> at SVE2, and I'm going "AVX512 really is nasty, isn't it"?
>
> And by now it's the third big generation, and the "it wasn't clear what the right answer was"
> is no longer an excuse for doing things wrong. People knew that scaling up and down the CPU
> stack was an issue. This wasn't something where Intel couldn't have seen it coming - when Intel
> was designing AVX512, Intel was still trying to also enter the smartphone and IoT area.
>
> Have I sufficiently explained why I absolutely despise AVX512?
>
> And yes, maybe in five years, AVX512 is there everywhere and my fragmentation argument goes away.
>
> Buy maybe in five years, SVE2 is everywhere too, and is happily working in cellphones and in supercomputers,
> and I think I won't be the only person in the room that says "AVX512 is a butt-ugly disgrace".
>
> We'll see, even if it might take years. I'm happy to be proven wrong.
>
> And I'm here for the heated technical discussion anyway. Tell me why I'm a pinhead
> and a nincompoop, and why SVE2 is so bad, and why AVX512 is clearly better.
>
> Because this forum is about architecture design and implementation, isn't it? So I think
> it's very fair to put down that gauntlet: AVX512 vs SVE2. "Gong plays" - FIGHT!
>
> Linus

< Previous Post in ThreadNext Post in Thread >
TopicPosted ByDate
Alder Lake and AVX-512me2020/07/11 06:02 AM
  Alder Lake and AVX-512Linus Torvalds2020/07/11 10:41 AM
    informative (NT)blue2020/07/11 11:40 AM
    grumpyMichael S2020/07/11 11:51 AM
      grumpyme2020/07/11 12:27 PM
    area and power cost of AVX-512Michael S2020/07/11 11:58 AM
      area and power cost of AVX-512Anon2020/07/11 03:35 PM
        area and power cost of AVX-512Michael S2020/07/12 03:16 AM
          area and power cost of AVX-512Travis Downs2020/07/12 08:13 AM
      area and power cost of AVX-512Travis Downs2020/07/11 06:19 PM
    Alder Lake and AVX-512Maynard Handley2020/07/11 01:02 PM
      Alder Lake and AVX-512Ungo2020/07/11 04:28 PM
        Alder Lake and AVX-512Maynard Handley2020/07/11 09:16 PM
      Alder Lake and AVX-512Linus Torvalds2020/07/11 05:51 PM
        Alder Lake and AVX-5122020/07/12 12:48 PM
          Alder Lake and AVX-512Michael S2020/07/12 02:07 PM
          HDRAnon32020/07/12 02:42 PM
            HDR10 in Kaby Lake?David Kanter2020/07/12 04:09 PM
              HDR10 in Kaby Lake?Maynard Handley2020/07/12 05:13 PM
                Thanks for the link (NT)David Kanter2020/07/12 05:43 PM
              HDR10 in Kaby Lake?Anon32020/07/13 12:36 AM
        Alder Lake and AVX-512Dummond D. Slow2020/07/12 02:00 PM
        AVX-512 with narrow ex units?m2020/07/23 11:10 AM
          AVX-512 with narrow ex units?Anon2020/07/23 11:53 AM
            AVX-512 with narrow ex units?Paul A. Clayton2020/07/23 05:32 PM
              AVX-512 with narrow ex units?Anon2020/07/23 05:50 PM
                AVX-512 with narrow ex units?Paul A. Clayton2020/07/23 06:45 PM
                  AVX-512 with narrow ex units?Anon2020/07/23 07:15 PM
                    AVX-512 with narrow ex units?Jukka Larja2020/07/24 03:44 AM
                      AVX-512 with narrow ex units?Gabriele Svelto2020/07/24 01:56 PM
                        AVX-512 with narrow ex units?Jouni Osmala2020/07/24 08:22 PM
                          AVX-512 with narrow ex units?Jukka Larja2020/07/25 12:32 AM
                      AVX-512 with narrow ex units?Eugene Nalimov2020/07/25 04:56 PM
                        AVX-512 with narrow ex units?Jukka Larja2020/07/26 12:28 AM
                        AVX-512 with narrow ex units?Gabriele Svelto2020/07/26 01:22 PM
                          AVX-512 with narrow ex units?Jukka Larja2020/07/27 06:00 AM
          AVX-512 with narrow ex units?-.-2020/07/23 05:32 PM
            AVX-512 with narrow ex units?Travis Downs2020/07/24 04:01 PM
    Alder Lake and AVX-512Jörn Engel2020/07/11 03:45 PM
      Alder Lake and AVX-512Chester2020/07/11 04:26 PM
        Alder Lake and AVX-512Jörn Engel2020/07/11 05:22 PM
        Alder Lake and AVX-512Michael S2020/07/12 01:02 AM
        Alder Lake and AVX-512Travis Downs2020/07/13 08:01 PM
      Alder Lake and AVX-512Linus Torvalds2020/07/11 05:54 PM
        Alder Lake and AVX-512Jörn Engel2020/07/11 07:01 PM
          Alder Lake and AVX-512N Owen2020/07/11 11:37 PM
            Alder Lake and AVX-512Michael S2020/07/12 12:48 AM
            Alder Lake and AVX-512anon22020/07/12 06:13 PM
          Alder Lake and AVX-512Travis Downs2020/07/13 08:09 PM
            Alder Lake and AVX-512Jörn Engel2020/07/13 10:42 PM
      Alder Lake and AVX-512Doug S2020/07/11 10:49 PM
        Alder Lake and AVX-512Michael S2020/07/12 12:53 AM
    Alder Lake and AVX-512Travis Downs2020/07/11 06:03 PM
      Alder Lake and AVX-512Veedrac2020/07/11 06:43 PM
        Alder Lake and AVX-512anon22020/07/12 12:31 AM
          Alder Lake and AVX-512Veedrac2020/07/12 03:01 AM
            Alder Lake and AVX-512anon22020/07/12 02:26 PM
              Alder Lake and AVX-512Anon32020/07/12 03:07 PM
                Alder Lake and AVX-512anon22020/07/12 04:39 PM
              Alder Lake and AVX-512Veedrac2020/07/12 03:21 PM
                Alder Lake and AVX-512anon22020/07/12 04:33 PM
                  Alder Lake and AVX-512Veedrac2020/07/12 04:54 PM
                    Alder Lake and AVX-512anon22020/07/12 05:20 PM
                  Alder Lake and AVX-512David Hess2020/07/12 06:32 PM
                    Alder Lake and AVX-512anon22020/07/12 07:41 PM
                Alder Lake and AVX-5122020/07/13 03:02 AM
                  Alder Lake and AVX-512anon22020/07/13 06:25 PM
                    PentiumMMX vs Transmeta's VLIW in hindsight2020/07/19 05:16 AM
                      PentiumMMX vs Transmeta's VLIW in hindsightMaynard Handley2020/07/19 09:47 AM
                      PentiumMMX vs Transmeta's VLIW in hindsightanon22020/07/19 02:24 PM
                      VLIW, OOO, Pairing, and FusionChester2020/07/19 09:16 PM
                        Poulson was in-order (NT)anon22020/07/19 11:20 PM
                        VLIW, OOO, Pairing, and FusionMichael S2020/07/19 11:48 PM
                        Itanium is NOT VLIWHeikki Kultala2020/07/20 01:27 PM
                          Itanium is NOT VLIWAdrian2020/07/20 10:03 PM
                            Itanium crappiness and EPIC - and could EPIC still have something good in it?Heikki Kultala2020/07/21 02:38 AM
                              Itanium crappiness and EPIC - and could EPIC still have something good in it?anon22020/07/21 04:03 AM
                                Itanium crappiness and EPIC - and could EPIC still have something good in it?dmcq2020/07/21 02:27 PM
                              Itanium crappiness and EPIC - and could EPIC still have something good in it?j2020/07/21 07:54 AM
                                Itanium crappiness and EPIC - and could EPIC still have something good in it?Tim McCaffrey2020/07/21 09:30 AM
                              Itanium crappiness and EPIC - and could EPIC still have something good in it?Linus Torvalds2020/07/21 08:13 AM
                                Itanium is not synomym of EPIC. Itanium is just the most common EPIC-style architectureHeikki Kultala2020/07/22 11:31 AM
                                  Turn that on its head?Ray2020/07/22 11:49 AM
                                    Turn that on its head?Anon2020/07/22 12:53 PM
                                    Turn that on its head?Maynard Handley2020/07/22 01:37 PM
                                    Turn that on its head?anon22020/07/22 02:32 PM
                                    Turn that on its head?anon32020/07/22 03:45 PM
                                    Turn that on its head?Heikki Kultala2020/07/23 01:53 AM
                                      Turn that on its head?Anon2020/07/23 09:20 AM
                                        Turn that on its head?Heikki Kultala2020/07/23 10:21 AM
                                          Turn that on its head?Brett2020/07/23 02:26 PM
                                            Turn that on its head?Brett2020/07/24 03:22 AM
                                      Bundling OOO entries does this implicitlyDavid Kanter2020/07/23 09:56 AM
                                      Turn that on its head?anon2020/07/23 10:49 AM
                                  Itanium is not synomym of EPIC. Itanium is just the most common EPIC-style architectureMaynard Handley2020/07/22 01:29 PM
                                  Itanium is not synomym of EPIC. Itanium is just the most common EPIC-style architecturewumpus2020/07/22 02:16 PM
                                    Itanium is not synomym of EPIC. Itanium is just the most common EPIC-style architectureDoug S2020/07/22 09:37 PM
                                      what Intel would have doneMichael S2020/07/22 11:46 PM
                                        what Intel would have doneDoug S2020/07/23 08:52 AM
                                        what Intel would have doneAnon2020/07/23 09:25 AM
                                          what Intel would have doneMichael S2020/07/23 10:23 AM
                                            what Intel would have doneMontaray Jack2020/07/23 05:08 PM
                                    Itanium is not synomym of EPIC. Itanium is just the most common EPIC-style architectureHeikki Kultala2020/07/22 10:47 PM
                                      Itanium is not synomym of EPIC. Itanium is just the most common EPIC-style architecturewumpus2020/07/23 12:46 PM
                                  Itanium is not synomym of EPIC. Itanium is just the most common EPIC-style architectureMichael S2020/07/22 11:56 PM
                                    Itanium is not synomym of EPIC. Itanium is just the most common EPIC-style architectureHeikki Kultala2020/07/23 01:44 AM
                          thanksChester2020/07/24 02:50 PM
      Alder Lake and AVX-512Linus Torvalds2020/07/11 06:46 PM
        Alder Lake and AVX-512never_released2020/07/11 07:54 PM
          Alder Lake and AVX-512Michael S2020/07/12 01:25 AM
        Alder Lake and AVX-512anon22020/07/12 12:36 AM
      Alder Lake and AVX-512Doug S2020/07/11 11:01 PM
      Alder Lake and AVX-512Michael S2020/07/12 01:41 AM
        Alder Lake and AVX-512rwessel2020/07/12 09:17 AM
      Alder Lake and AVX-512-.-2020/08/18 02:24 AM
        Alder Lake and AVX-512Travis Downs2020/08/18 10:04 PM
    Alder Lake and AVX-512Geoff Langdale2020/07/11 06:49 PM
      Alder Lake and AVX-512anon2020/07/11 07:12 PM
      Alder Lake and AVX-512Jörn Engel2020/07/11 07:33 PM
        Alder Lake and AVX-512Michael S2020/07/12 02:00 AM
        Alder Lake and AVX-512Jukka Larja2020/07/12 07:51 AM
          Alder Lake and AVX-512Maynard Handley2020/07/12 09:30 AM
            Alder Lake and AVX-512Jukka Larja2020/07/13 06:43 AM
              Alder Lake and AVX-512Montaray Jack2020/07/23 06:20 PM
                Alder Lake and AVX-512Jukka Larja2020/07/24 03:57 AM
          Alder Lake and AVX-512Jörn Engel2020/07/12 10:35 AM
            Alder Lake and AVX-512Linus Torvalds2020/07/12 11:01 AM
              Alder Lake and AVX-512Linus Torvalds2020/07/12 11:15 AM
                Alder Lake and AVX-512anonymou52020/07/12 12:50 PM
                  Alder Lake and AVX-512Linus Torvalds2020/07/12 01:31 PM
                    Alder Lake and AVX-512anonymou52020/07/12 02:09 PM
                      Alder Lake and AVX-512Linus Torvalds2020/07/12 03:25 PM
                        Alder Lake and AVX-512anonymou52020/07/12 07:34 PM
                          Alder Lake and AVX-512Jose2020/07/13 12:35 AM
                  Alder Lake and AVX-512gallier22020/07/13 01:11 AM
                Alder Lake and AVX-512gallier22020/07/13 01:01 AM
                  Alder Lake and AVX-512Linus Torvalds2020/07/13 10:06 AM
                    Alder Lake and AVX-512Doug S2020/07/13 11:11 AM
                      Alder Lake and AVX-512Brett2020/07/14 01:34 AM
                        Alder Lake and AVX-512Linus Torvalds2020/07/14 08:02 AM
                          Alder Lake and AVX-512Maynard Handley2020/07/14 11:40 AM
                            Alder Lake and AVX-512Michael S2020/07/14 11:48 AM
                            Alder Lake and AVX-512Linus Torvalds2020/07/15 12:37 AM
                              OS X file names normalizationMichael S2020/07/15 01:26 AM
                                OS X file names normalizationSimon Farnsworth2020/07/15 03:16 AM
                                  OS X file names normalizationMichael S2020/07/15 09:51 AM
                                    OS X file names normalizationSimon Farnsworth2020/07/15 11:27 AM
                                OS X file names normalizationDoug S2020/07/15 09:46 AM
                                  OS X file names normalizationMichael S2020/07/15 10:05 AM
                                    OS X file names normalizationLinus Torvalds2020/07/15 11:58 AM
                                      OS X file names normalizationLinus Torvalds2020/07/15 01:21 PM
                                      OS X file names normalizationgallier22020/07/15 10:57 PM
                                    OS X file names normalizationgallier22020/07/15 10:44 PM
                                  OS X file names normalizationRob Thorpe2020/07/15 10:23 AM
                                    OS X file names normalizationDoug S2020/07/15 12:32 PM
                                      OS X file names normalizationMaynard Handley2020/07/15 04:20 PM
                                        OS X file names normalizationLinus Torvalds2020/07/15 07:37 PM
                                          OS X file names normalizationAnon32020/07/16 12:43 PM
                                            OS X file names normalizationDoug S2020/07/16 02:38 PM
                                              OS X file names normalizationLinus Torvalds2020/07/16 11:21 PM
                                                OS X file names normalizationAnon32020/07/17 01:15 AM
                                                  OS X file names normalizationJukka Larja2020/07/17 05:40 AM
                                                OS X file names normalizationgallier22020/07/17 02:19 AM
                                                  OS X file names normalizationLinus Torvalds2020/07/17 08:41 AM
                                                    OS X file names normalizationDummond D. Slow2020/07/17 08:54 AM
                                                      OS X file names normalizationLinus Torvalds2020/07/17 09:16 AM
                                                      OS X file names normalizationSimon Farnsworth2020/07/18 05:12 AM
                                              OS X file names normalizationAnon32020/07/17 01:04 AM
                                                OS X file names normalizationDoug S2020/07/17 09:15 AM
                              Alder Lake and AVX-512Maynard Handley2020/07/15 09:32 AM
                            File Systems and VC ProblemsRob Thorpe2020/07/15 06:24 AM
                    vectorization of utf8Robert David Graham2020/07/13 01:36 PM
                      vectorization of utf8anon22020/07/13 04:07 PM
                        vectorization of utf8Robert David Graham2020/07/13 07:36 PM
                          vectorization of utf8anon22020/07/13 10:23 PM
                        vectorization of utf8Maynard Handley2020/07/13 09:46 PM
                      vectorization of utf8Gabriele Svelto2020/07/15 02:27 AM
                    Alder Lake and AVX-512gallier22020/07/14 12:13 AM
              Alder Lake and AVX-512Jörn Engel2020/07/12 12:29 PM
                Alder Lake and AVX-512Linus Torvalds2020/07/12 01:08 PM
                  Alder Lake and AVX-512Jörn Engel2020/07/12 05:26 PM
                    Alder Lake and AVX-512-.-2020/07/12 06:11 PM
                      Alder Lake and AVX-512Jörn Engel2020/07/12 06:43 PM
            Alder Lake and AVX-512Jukka Larja2020/07/13 07:38 AM
              Alder Lake and AVX-512Jörn Engel2020/07/13 09:10 AM
                Alder Lake and AVX-512Michael S2020/07/13 10:02 AM
                  Alder Lake and AVX-512Jörn Engel2020/07/13 10:22 AM
                    Alder Lake and AVX-512Michael S2020/07/13 11:10 AM
                      Alder Lake and AVX-512Jörn Engel2020/07/13 03:03 PM
                Alder Lake and AVX-512Jukka Larja2020/07/14 05:53 AM
      Alder Lake and AVX-512Linus Torvalds2020/07/11 07:34 PM
        Alder Lake and AVX-512Brett2020/07/11 08:02 PM
          Alder Lake and AVX-512David Hess2020/07/13 11:36 AM
            Alder Lake and AVX-512anonymou52020/07/13 12:01 PM
              Alder Lake and AVX-512Brett2020/07/13 03:19 PM
        Alder Lake and AVX-512Geert2020/07/11 08:36 PM
          AMD's FPUChester2020/07/12 01:28 AM
            Is 3|5 lower than 4?Michael S2020/07/12 02:59 AM
              Is 3|5 lower than 4?Chester2020/07/12 04:54 AM
        Alder Lake and AVX-512Geoff Langdale2020/07/11 10:45 PM
          Alder Lake and AVX-512me2020/07/12 02:44 AM
          Alder Lake and AVX-512Michael S2020/07/12 03:09 AM
          Alder Lake and AVX-512Linus Torvalds2020/07/12 10:35 AM
            ~80% of details are wrong. So what one can expect from conclusions? :( (NT)Michael S2020/07/12 10:57 AM
              ~80% of details are wrong. So what one can expect from conclusions? :(anonymous22020/07/12 11:50 AM
            Alder Lake and AVX-512nobody in particular2020/07/12 11:25 AM
              Alder Lake and AVX-512Linus Torvalds2020/07/12 11:37 AM
                Alder Lake and AVX-512nobody in particular2020/07/12 11:43 AM
                  Alder Lake and AVX-512me2020/07/12 12:32 PM
                    Alder Lake and AVX-512Maynard Handley2020/07/12 07:51 PM
            Alder Lake and AVX-512UnmaskedUnderflow2020/07/12 11:33 AM
            AVX-512 vs SVE2-.-2020/07/12 05:22 PM
              AVX-512 vs SVE2noko2020/07/12 11:12 PM
                AVX-512 vs SVE2-.-2020/07/13 03:00 AM
            Alder Lake and AVX-512Geoff Langdale2020/07/12 07:18 PM
              Could you please stop top-posting (NT)Jukka Larja2020/07/13 07:45 AM
              Alder Lake and AVX-512Romain Dolbeau2020/07/15 12:00 AM
            Alder Lake and AVX-512Spiteful Sprites2020/07/13 03:59 AM
              Alder Lake and AVX-512nobody in particular2020/07/13 08:12 AM
                Alder Lake and AVX-512Spiteful Sprites2020/07/13 03:21 PM
                  Alder Lake and AVX-512Jouni Osmala2020/07/14 01:55 AM
                  RISC-V & commercial support (was: Alder Lake and AVX-512)Romain Dolbeau2020/07/15 12:11 AM
                    RISC-V & commercial support (was: Alder Lake and AVX-512)Romain Dolbeau2020/07/15 12:13 AM
              Alder Lake and AVX-512Linus Torvalds2020/07/13 10:10 AM
            AVX-512/SVE & HPC (was: Alder Lake and AVX-512)Romain Dolbeau2020/07/14 09:09 AM
              AVX-512/SVE & HPC (was: Alder Lake and AVX-512)anon2020/07/14 09:53 AM
                AVX-512/SVE & HPC (was: Alder Lake and AVX-512)Romain Dolbeau2020/07/14 10:27 AM
                  AVX-512/SVE & HPC (was: Alder Lake and AVX-512)Maynard Handley2020/07/14 11:52 AM
                  AVX-512/SVE & HPC (was: Alder Lake and AVX-512)Doug S2020/07/14 12:43 PM
                  AVX-512/SVE & HPC (was: Alder Lake and AVX-512)anon2020/07/14 02:01 PM
              AVX-512/SVE & HPC (was: Alder Lake and AVX-512)Linus Torvalds2020/07/14 11:00 AM
                AVX-512/SVE & HPC (was: Alder Lake and AVX-512)Romain Dolbeau2020/07/14 10:42 PM
                  Configurable cache line size?Doug S2020/07/15 09:56 AM
                    Configurable cache line size?dmcq2020/07/15 02:43 PM
                    Configurable cache line size?Romain Dolbeau2020/07/15 10:37 PM
                    Configurable cache line size?NoSpammer2020/07/16 12:27 AM
                    Configurable cache line size?Pixie2020/07/16 09:55 AM
                      Configurable cache line size?Etienne2020/07/17 12:03 AM
                        Configurable cache line size?Hugo Décharnes2020/07/18 01:11 AM
                  Cache line sizeMark Roulo2020/07/15 05:10 PM
                    Cache line sizeanon2020/07/15 05:46 PM
                  AVX-512/SVE & HPC (was: Alder Lake and AVX-512)Gabriele Svelto2020/07/17 01:30 AM
                    AVX-512/SVE & HPC (was: Alder Lake and AVX-512)dmcq2020/07/17 02:34 AM
                      AVX-512/SVE & HPC (was: Alder Lake and AVX-512)zArchJon2020/07/17 12:16 PM
            Macro-instructions to the rescue2020/07/24 11:56 AM
              Some fundamentals haven't changedChester2020/07/24 02:59 PM
                Some fundamentals haven't changed2020/07/24 03:24 PM
                  Some fundamentals haven't changeddmcq2020/07/25 06:58 AM
                    Some fundamentals haven't changed2020/07/25 10:05 AM
                    Some fundamentals haven't changedBrett2020/07/25 01:16 PM
                      Some fundamentals haven't changedBrett2020/07/25 01:27 PM
                      What belt is.Heikki Kultala2020/07/26 06:49 AM
                        What belt is.Michael S2020/07/26 09:00 AM
                          What belt is.Brett2020/07/26 10:46 PM
                            What belt is.Michael S2020/07/26 11:52 PM
                              What belt is.Brett2020/07/27 06:25 AM
                                What belt is.Doug S2020/07/27 12:31 PM
                                  What belt is.Andrew Clough2020/07/28 05:11 AM
                                    What belt is.dmcq2020/07/28 07:17 AM
                                      Mill Compiler still MIA?Geoff Langdale2020/07/28 04:04 PM
                                        If they release the compiler, how they will blame the still-in-development compiler for the lacklust (NT)Anon2020/07/28 04:20 PM
                                          If they release the compiler, how they will blame the still-in-development compiler for the lacklustAnon2020/07/28 04:20 PM
                                        Apparently they're busy writing a kernel...Anon2020/07/29 02:03 AM
                                          Apparently they're busy writing a kernel...dmcq2020/07/29 02:39 AM
                        What belt is.2020/07/26 10:44 AM
                          What belt is.anonymous22020/07/26 11:02 AM
                            What belt is.Doug S2020/07/26 02:26 PM
                              What belt is.2020/07/26 03:02 PM
        gooduseruser2020/07/12 09:06 AM
      Alder Lake and AVX-512-.-2020/07/11 08:03 PM
        Alder Lake and AVX-512-.-2020/07/11 08:07 PM
      Alder Lake and AVX-512j2020/07/12 11:29 PM
        Alder Lake and AVX-512Michael S2020/07/13 12:12 AM
          Alder Lake and AVX-512j2020/07/13 01:58 AM
            Alder Lake and AVX-512dmcq2020/07/13 03:53 PM
              Alder Lake and AVX-512Michael S2020/07/13 11:57 PM
                Alder Lake and AVX-512Maynard Handley2020/07/14 09:26 AM
                Alder Lake and AVX-512dmcq2020/07/14 11:33 AM
                  Alder Lake and AVX-512dmcq2020/07/14 02:43 PM
                    Alder Lake and AVX-512Michael S2020/07/14 11:55 PM
                      Alder Lake and AVX-512dmcq2020/07/15 01:19 AM
                        Alder Lake and AVX-512Michael S2020/07/15 01:34 AM
                          Alder Lake and AVX-512dmcq2020/07/15 02:03 AM
                            Alder Lake and AVX-512Michael S2020/07/15 08:43 AM
                              Alder Lake and AVX-512dmcq2020/07/15 08:54 AM
                                Alder Lake and AVX-512Michael S2020/07/15 10:35 AM
                                  Alder Lake and AVX-512dmcq2020/07/15 02:18 PM
                                    GV100 + POWER9Michael S2020/07/16 12:17 AM
                                      GV100 + POWER9dmcq2020/07/16 07:58 AM
                                        GV100 + POWER9dmcq2020/07/16 08:10 AM
                        Alder Lake and AVX-512dmcq2020/07/15 01:48 AM
    Alder Lake and AVX-512o2020/07/12 02:08 AM
    Alder Lake and AVX-5122020/07/12 10:07 AM
      Alder Lake and AVX-5122020/07/12 10:32 AM
      Alder Lake and AVX-512Linus Torvalds2020/07/12 10:39 AM
        Alder Lake and AVX-5122020/07/12 11:47 AM
        Alder Lake and AVX-512Michael S2020/07/12 12:18 PM
          x87 crapHeikki Kultala2020/07/12 12:30 PM
            x87 crapMichael S2020/07/12 12:37 PM
              x87 crapHeikki kultala2020/07/12 01:11 PM
                x87 crapMichael S2020/07/12 01:50 PM
                  Sparc and PA-RISC vs pentium FP performanceHeikki Kultala2020/07/13 12:14 AM
                    Sparc and PA-RISC vs pentium FP performanceanonymous22020/07/13 09:48 AM
          Alder Lake and AVX-512Doug S2020/07/12 02:33 PM
            Alder Lake and AVX-512Michael S2020/07/12 03:10 PM
    Alder Lake and AVX-512David Kanter2020/07/12 04:01 PM
      Alder Lake and AVX-512anon2020/07/12 04:40 PM
      ~0% of users do much FP outside of GPUs for games (NT)anonymous22020/07/12 04:47 PM
        ~0% of users do much FP outside of GPUs for gamesMaynard Handley2020/07/12 11:26 PM
        not trueChester2020/07/12 11:37 PM
          not trueMichael S2020/07/13 12:29 AM
            not trueChester2020/07/13 12:59 AM
              not trueanonymous22020/07/13 09:32 AM
                not trueMaynard Handley2020/07/13 01:30 PM
                  not trueChester2020/07/14 04:47 AM
            not trueDoug S2020/07/13 11:30 AM
              not trueAnon2020/07/13 12:16 PM
                not trueMaynard Handley2020/07/13 01:39 PM
              not trueMaynard Handley2020/07/13 01:38 PM
          not trueLinus Torvalds2020/07/13 10:27 AM
            not trueDummond D. Slow2020/07/13 01:10 PM
              not trueMaynard Handley2020/07/13 01:49 PM
                not trueDummond D. Slow2020/07/13 02:38 PM
            not true (about FP, not avx-512)Chester2020/07/17 09:37 AM
  Alder Lake and AVX-512Travis Downs2020/07/11 05:45 PM
    Alder Lake and AVX-512-.-2020/07/11 05:57 PM
      Alder Lake and AVX-512-.-2020/07/12 03:26 PM
Reply to this Topic
Name:
Email:
Topic:
Body: No Text
How do you spell avocado?