ARMv8 cleanliness

Article: Microservers must Specialize to Survive
By: Linus Torvalds (torvalds.delete@this.linux-foundation.org), February 17, 2013 10:54 am
Room: Moderated Discussions
⚛ (0xe2.0x9a.0x9b.delete@this.gmail.com) on February 17, 2013 10:49 am wrote:
> >
> > In contrast, multiple CC registers are just stupid.
>
> Isn't it true that the following code could run faster with 2 CC registers:
>
> if a==b && c==d { ... }

No. For multiple reasons.

(a) The above isn't nearly as common as the single test one, so even if it was faster, it's not worth worrying about. But it's not faster even for the combined case:

(b) multiple cc registers need extra bits in the instruction to specify which cc. End result: either you have huge instructions and your I$ sucks (Itanium), or more commonly you have one primary cc, and need special instructions for the other ones. In either case, it adds complexity.

(c) The above isn't nearly as common as the single test one, so even if it was faster, it's not worth worrying about. But it's not even faster.

(d) you can do it with a single CC and trivial optimizations. For example, in this case, you can do it with two subtracts and one 'or', and then checking the result of the 'or' for being zero. So your example could be trivially done with three instructions, and the 'or' just sets the CC bits implicitly.

(e) even though you can do it with pure arithmetic and just a single CC setting instruction (which is not uncommon), it's not even usually *worth* it. The obvious "just do two compares and two jumps" is likely the optimal code sequence, much better than trying to combine conditionals. Why? Branches usually predict well, and branch prediction makes conditional branches free (and even "better than free", because you can speculate and re-order across them, unlike data dependencies.

(f) multiple CC's means you also have to spend more effort on renaming them. x86 gets some of this with it's "single" register (it's really three sets of bits: the "status flags" end up being split into two by the fact that "Carry" is special with some instructions setting it but not others, and then you have the special system bits). But powerpc has the same exact problem, with its eight sets of 4-bit groups. So x86 has extra complexity for its own historical accidents, but the powerpc people added their stupidities on purpose!

Btw, that (e) thing is a big issue. Playing games with combined conditionals is usually just a huge waste of time - even if you were to save an instruction (which you generally don't), you do so at the cost of making the critical data-dependency chain longer and the code this slower.

Put another way: one point of combining conditionals is to remove conditional branches by replacing them with data flow, but conditional branches are just about the cheapest instruction you can have when they predict well. So not only do you need multiple conditionals to begin with, they all have to be unlikely! And please do note the "all" part. That's what makes the use of them such a spectacular failure. There simply aren't enough places for them to matter, and the places where they *do* matter can be written (admittedly often with slightly more complexity) with just a single CC and conditional moves/sets anyway.

End result: multiple CC's are just a f*cking stupid idea. Yes, you can find cases where they help, but they are much rarer than you'd think. The fact that branch prediction works really well is one primary downfall of them, but the thing is, even if you ignore that one, most of the time there is little disadvantage to a single CC, and arithmetic either on the sources (like in your very own example, as I showed you!) or on conditional moves will not be noticeably worse even with a single CC.

The only really valid reason for multiple CC seems to be "I'm a failed architecture, and I will do things in-order, and multiple CC's allow me to do lots of explicit scheduling in software by the compiler".

And quite frankly, anybody who believes that is a good reason for them should join the Itanium team and try to take over the world. At least the PowerPC people had *some* excuse for believing that 25 years ago. They were wrong too, but they didn't have tons of history to show them wrong.

Seriously. Multiple CC's is completely idiotic. Thinking that in-order machines and relying on the compiler to schedule instructions makes sense for performance is f*cking moronic.

Linus
< Previous Post in ThreadNext Post in Thread >
TopicPosted ByDate
Article Online: Microservers must Specialize to SurviveDavid Kanter2013/01/28 12:47 PM
  Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/29 03:42 AM
    Article Online: Microservers must Specialize to SurviveMichael S2013/01/29 05:09 AM
      Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/29 06:01 AM
        Article Online: Microservers must Specialize to SurviveDavid Kanter2013/01/29 12:35 PM
          Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/29 01:42 PM
            Article Online: Microservers must Specialize to SurviveDavid Kanter2013/01/29 11:12 PM
              Article Online: Microservers must Specialize to SurviveMichael S2013/01/30 01:06 AM
              Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/30 08:58 AM
              Article Online: Microservers must Specialize to SurviveDoug S2013/01/30 11:38 AM
                FRU type and granularity selectionPaul A. Clayton2013/01/30 01:29 PM
                  FRU type and granularity selectionrwessel2013/01/30 03:00 PM
                    FRU type and granularity selectionEtienne2013/01/31 02:26 AM
                Article Online: Microservers must Specialize to SurviveMaynard Handley2013/02/13 01:46 PM
                  Article Online: Microservers must Specialize to SurviveDavid Kanter2013/02/16 02:16 PM
                    Article Online: Microservers must Specialize to SurviveDoug S2013/02/17 11:24 AM
        Article Online: Microservers must Specialize to SurviveJohan2013/02/01 12:40 AM
          Article Online: Microservers must Specialize to SurvivePer Hesselgren2013/02/01 02:06 AM
            Article Online: Microservers must Specialize to SurvivePer Hesselgren2013/02/01 02:13 AM
    Article Online: Microservers must Specialize to Survivebakaneko2013/01/29 05:49 AM
      Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/29 06:19 AM
        Article Online: Microservers must Specialize to Survivebakaneko2013/01/29 08:47 AM
          Article Online: Microservers must Specialize to Survivebakaneko2013/01/29 01:18 PM
            Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/29 05:14 PM
              Article Online: Microservers must Specialize to SurviveDavid Kanter2013/01/29 10:51 PM
                Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/30 07:34 AM
                  Article Online: Microservers must Specialize to Surviveanon2013/01/31 05:45 AM
                    Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/31 11:25 AM
                      Article Online: Microservers must Specialize to Surviveanon2013/01/31 11:47 AM
                        Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/31 12:36 PM
                          Article Online: Microservers must Specialize to Surviveanon2013/01/31 03:59 PM
                            Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/31 04:37 PM
                              Article Online: Microservers must Specialize to Surviveanon2013/01/31 05:47 PM
                                Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/31 06:16 PM
                                  Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/31 06:36 PM
                                    Article Online: Microservers must Specialize to Surviveanon2013/02/01 12:47 AM
                                      Article Online: Microservers must Specialize to SurviveRichard Cownie2013/02/01 03:26 AM
                                        Article Online: Microservers must Specialize to Surviveanon2013/02/01 04:56 AM
                                          Article Online: Microservers must Specialize to SurviveRichard Cownie2013/02/01 05:35 AM
                                            Article Online: Microservers must Specialize to SurviveMichael S2013/02/01 06:07 AM
                                            Article Online: Microservers must Specialize to Surviveanon2013/02/01 07:08 AM
                                              Article Online: Microservers must Specialize to SurviveRichard Cownie2013/02/01 07:49 AM
                                                Article Online: Microservers must Specialize to Surviveanon2013/02/01 08:36 AM
                                                  Article Online: Microservers must Specialize to SurviveRichard Cownie2013/02/01 09:11 AM
                                                    Article Online: Microservers must Specialize to Surviveanon2013/02/01 05:57 PM
                                                      Article Online: Microservers must Specialize to Surviverwessel2013/02/02 12:42 AM
                                                      Article Online: Microservers must Specialize to SurviveRichard Cownie2013/02/02 05:41 AM
                                                        Article Online: Microservers must Specialize to SurviveRicardo B2013/02/02 01:14 PM
                                                          Article Online: Microservers must Specialize to SurviveRichard Cownie2013/02/02 01:50 PM
                                                            Article Online: Microservers must Specialize to SurviveRicardo B2013/02/02 03:05 PM
                                                              Article Online: Microservers must Specialize to SurviveMichael S2013/02/02 03:20 PM
                                                              Article Online: Microservers must Specialize to SurviveRichard Cownie2013/02/02 04:05 PM
                                                                ASP estimatesRichard Cownie2013/02/02 05:07 PM
                                                                  ASP estimatesRicardo B2013/02/02 05:48 PM
                                                                    ASP estimatesRichard Cownie2013/02/02 06:04 PM
                                                                      ASP estimatesanon2013/02/02 09:19 PM
                                                                        ASP estimatesRichard Cownie2013/02/03 05:06 AM
                                                                          ASP estimates...cache?Per Hesselgren2013/02/03 11:08 AM
                                                                      ASP estimatesMichael S2013/02/03 01:51 AM
                                                                        ASP estimatesRichard Cownie2013/02/03 05:10 AM
                                                                          ASP estimatesDaniel Bizo2013/02/04 02:45 PM
                                                                            ASP estimatesRichard Cownie2013/02/04 04:01 PM
                                                                              ASP estimatesJS2013/02/05 03:25 AM
                                                                              ASP estimatesDaniel Bizo2013/02/05 05:31 AM
                                                                                ASP estimatesRichard Cownie2013/02/05 05:46 AM
                                                                  ARM OEMs get free silicon?someone2013/02/03 12:44 PM
                                                                    ARM OEMs get free silicon?Richard Cownie2013/02/03 07:28 PM
                                                                      ARM OEMs get free silicon?Doug S2013/02/04 10:08 AM
                                                                        ARM OEMs get free silicon?Richard Cownie2013/02/04 11:17 AM
                                                                          ARM OEMs get free silicon?geeker2013/02/06 11:16 AM
                                                                            ARM OEMs get free silicon?Gabriele Svelto2013/02/07 03:18 AM
                                                                              ARM OEMs get free silicon?izotop2013/02/07 05:11 AM
                                                                            ARM OEMs get free silicon?Richard Cownie2013/02/07 05:48 AM
                                                                Article Online: Microservers must Specialize to SurviveRicardo B2013/02/02 05:31 PM
                                                                  Article Online: Microservers must Specialize to SurviveRichard Cownie2013/02/02 05:55 PM
                                                                    Article Online: Microservers must Specialize to SurviveRicardo B2013/02/02 06:25 PM
                                                                      Article Online: Microservers must Specialize to SurviveRichard Cownie2013/02/02 06:50 PM
                                                                        Article Online: Microservers must Specialize to SurviveRicardo B2013/02/02 07:22 PM
                                                                        Article Online: Microservers must Specialize to SurviveBrendan2013/02/02 11:48 PM
                                                                        Article Online: Microservers must Specialize to SurviveMichael S2013/02/03 01:22 AM
                                                                    Article Online: Microservers must Specialize to Surviveanon2013/02/02 09:21 PM
                                                                      Article Online: Microservers must Specialize to SurviveMichael S2013/02/03 01:40 AM
                                                                        Article Online: Microservers must Specialize to Surviveanon2013/02/03 02:54 AM
                                                                      Overlooking the advantage (or not) of x86 in different marketsDoug S2013/02/03 12:54 PM
                                                                Article Online: Microservers must Specialize to Surviveanon2013/02/02 09:14 PM
                                                                  Article Online: Microservers must Specialize to Surviveanon2013/02/02 09:32 PM
                                                                    Article Online: Microservers must Specialize to SurviveRichard Cownie2013/02/03 05:24 AM
                                                        Article Online: Microservers must Specialize to Surviveanon2013/02/02 09:08 PM
                                          Article Online: Microservers must Specialize to SurviveMichael S2013/02/01 05:41 AM
                                            Article Online: Microservers must Specialize to Surviveanon2013/02/01 06:41 AM
                            Article Online: Microservers must Specialize to SurviveDoug S2013/02/01 03:41 PM
                              Article Online: Microservers must Specialize to Surviveanon2013/02/01 06:08 PM
                                Article Online: Microservers must Specialize to SurviveDoug S2013/02/02 01:38 PM
                                  Article Online: Microservers must Specialize to SurviveRicardo B2013/02/02 02:03 PM
              Article Online: Microservers must Specialize to Survivebakaneko2013/01/30 12:16 AM
        Article Online: Microservers must Specialize to Surviveanon2013/01/29 10:34 PM
    Article Online: Microservers must Specialize to Survivesomeone2013/01/29 07:58 AM
      Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/29 08:28 AM
      Article Online: Microservers must Specialize to SurviveMichael S2013/01/29 08:42 AM
      Article Online: Microservers must Specialize to SurviveMark Roulo2013/01/29 05:08 PM
        Article Online: Microservers must Specialize to Surviverwessel2013/01/29 09:15 PM
          Article Online: Microservers must Specialize to SurviveRichard Cownie2013/01/30 01:39 PM
            Article Online: Microservers must Specialize to Surviverwessel2013/01/30 02:54 PM
          Or compare to *desktop* ASPsMark Roulo2013/01/30 02:51 PM
            Or compare to *desktop* ASPsrwessel2013/01/30 03:07 PM
            Or compare to *desktop* ASPsCeleron2013/01/30 04:49 PM
            Or compare to *desktop* ASPsDoug S2013/01/30 08:50 PM
              Or compare to *desktop* ASPsrwessel2013/01/30 10:04 PM
              when thoughput matters, ultra-cheap Intel CPUs are not attractiveMichael S2013/01/31 01:59 AM
                when thoughput matters, ultra-cheap Intel CPUs are not attractiveDoug S2013/01/31 11:00 AM
                  when thoughput matters, ultra-cheap Intel CPUs are not attractiveMichael S2013/01/31 01:04 PM
                    Price/perf curve on intel.Jouni Osmala2013/01/31 10:28 PM
                    when thoughput matters, ultra-cheap Intel CPUs are not attractiveDoug S2013/02/01 03:45 PM
                      when thoughput matters, ultra-cheap Intel CPUs are not attractiverwessel2013/02/02 12:54 AM
              Or compare to *desktop* ASPsGabriele Svelto2013/01/31 02:33 AM
    Article Online: Microservers must Specialize to SurviveDoug S2013/01/29 09:36 AM
      Article Online: Microservers must Specialize to SurviveDavid Kanter2013/01/29 12:52 PM
        Article Online: Microservers must Specialize to SurviveARMandLeg2013/01/29 02:31 PM
        Article Online: Microservers must Specialize to SurviveNo2013/01/29 02:32 PM
          Article Online: Microservers must Specialize to SurviveMichael S2013/01/29 03:36 PM
            Article Online: Microservers must Specialize to SurviveDoug S2013/01/29 06:25 PM
        Article Online: Microservers must Specialize to SurviveDoug S2013/01/29 06:20 PM
          Article Online: Microservers must Specialize to SurviveEduardoS2013/01/30 02:48 AM
  Article Online: Microservers must Specialize to SurvivePer Hesselgren2013/01/29 08:08 AM
  Article Online: Microservers must Specialize to Survivecarop2013/01/29 01:55 PM
    Article Online: Microservers must Specialize to SurviveDavid Kanter2013/01/29 10:33 PM
      Article Online: Microservers must Specialize to SurviveGabriele Svelto2013/01/31 02:51 AM
    Article Online: Microservers must Specialize to Survivebakaneko2013/01/30 12:32 AM
      Cache capacity benefits (babbling a bit)Paul A. Clayton2013/01/30 12:42 PM
        Cache size experiments may have been done on ARMsMark Roulo2013/01/30 01:14 PM
          Way and line locking and associativityPaul A. Clayton2013/01/30 02:08 PM
            Way and line locking and associativityMark Roulo2013/01/30 02:37 PM
        Cache capacity benefits may have been done in simulationPatrick Chase2013/01/30 06:25 PM
          Simulation has benefits but is SLOWPaul A. Clayton2013/01/30 08:08 PM
            Simulation has benefits but is SLOWPatrick Chase2013/01/30 09:36 PM
              Simulation has benefits but is SLOWRichard Cownie2013/02/01 11:32 AM
                Simulation has benefits but is SLOWPatrick Chase2013/02/01 12:06 PM
                Simulation has benefits but is SLOWnone2013/02/01 12:13 PM
      Article Online: Microservers must Specialize to Survivesoupdragon2013/01/31 11:02 AM
    Article Online: Microservers must Specialize to SurvivePatrick Chase2013/01/30 11:26 AM
  4x or 10x advantageS. Rao2013/01/30 04:35 PM
    4x or 10x advantagerwessel2013/01/30 05:32 PM
      4x or 10x advantageS. Rao2013/02/03 09:32 PM
        4x or 10x advantageDavid Kanter2013/02/03 10:09 PM
        4x or 10x advantagerwessel2013/02/03 11:08 PM
          x86_64Richard Cownie2013/02/04 04:52 PM
            x86_64Michael S2013/02/05 01:51 AM
              x86_64Richard Cownie2013/02/05 03:33 AM
                x86_64EduardoS2013/02/05 03:41 AM
                  x86_64sJ2013/02/05 04:52 AM
                  x86_64Richard Cownie2013/02/05 05:47 AM
                x86_64someone2013/02/05 08:22 AM
                  x86_64Richard Cownie2013/02/05 08:44 AM
              "Just recompile"Mark Roulo2013/02/05 07:40 AM
                "Just recompile"Michael S2013/02/05 09:35 AM
                  "Just recompile"Mark Roulo2013/02/05 09:55 AM
  Virtualization and custom interconnectsGabriele Svelto2013/01/31 04:05 AM
  x86 penalty depends on performance and microarchitecturePatrick Chase2013/02/01 09:11 PM
    x86 penalty depends on performance and microarchitecturempx2013/02/02 03:31 AM
      x86 penalty depends on performance and microarchitecturePatrick Chase2013/02/02 08:27 AM
        Heterogenous multicore in serversPaul A. Clayton2013/02/02 09:25 AM
    x86 penalty depends on performance and microarchitectureanon2013/02/02 04:04 AM
      x86 penalty depends on performance and microarchitecturePatrick Chase2013/02/02 08:42 AM
        x86 penalty depends on performance and microarchitecturePatrick Chase2013/02/02 08:58 AM
        x86 penalty depends on performance and microarchitecturePatrick Chase2013/02/02 09:26 AM
        x86 penalty depends on performance and microarchitectureanon2013/02/02 04:49 PM
          x86 penalty depends on performance and microarchitecturePer Hesselgren2013/02/03 12:44 AM
            x86 penalty depends on performance and microarchitectureMichael S2013/02/03 01:59 AM
          x86 penalty depends on performance and microarchitecturePatrick Chase2013/02/03 01:27 PM
            x86 penalty depends on performance and microarchitectureanon2013/02/03 01:58 PM
              x86 penalty depends on performance and microarchitecturePatrick Chase2013/02/03 02:35 PM
                x86 penalty depends on performance and microarchitecturePatrick Chase2013/02/03 02:39 PM
                x86 penalty depends on performance and microarchitectureanon2013/02/03 05:08 PM
                  x86 penalty depends on performance and microarchitecturePatrick Chase2013/02/03 07:05 PM
                    x86 penalty depends on performance and microarchitectureanon2013/02/03 08:52 PM
                      x86 penalty depends on performance and microarchitectureDavid Kanter2013/02/03 10:23 PM
                        U shape curve on performance...Jouni Osmala2013/02/04 12:07 AM
                          U shape curve on performance...none2013/02/04 02:03 AM
                            U shape curve on performance...Michael S2013/02/04 06:55 AM
                              U shape curve on performance...Patrick Chase2013/02/04 09:14 AM
                                U shape curve on performance...Michael S2013/02/04 01:43 PM
                                  U shape curve on performance...Patrick Chase2013/02/04 03:06 PM
                            Microcode can be usefulPaul A. Clayton2013/02/04 07:08 AM
                          U shape curve on performance...Michael S2013/02/04 06:48 AM
                          U shape curve on performance...Patrick Chase2013/02/04 09:05 AM
                            It only works if ... ??Paul A. Clayton2013/02/04 11:20 AM
                              It only works if ... ??Patrick Chase2013/02/04 11:48 AM
                                It only works if ... ??Patrick Chase2013/02/04 12:02 PM
                                It only works if ... ??Patrick Chase2013/02/04 12:08 PM
                                  It only works if ... ??Patrick Chase2013/02/04 12:15 PM
                                  It only works if ... ??anon2013/02/04 04:45 PM
                            I don't follow...Megol2013/02/05 09:16 AM
                      x86 penalty depends on performance and microarchitecturerwessel2013/02/03 11:28 PM
            spec95 vs Spec2kMichael S2013/02/04 01:27 AM
              spec95 vs Spec2kPer Hesselgren2013/02/04 03:42 AM
              spec95 vs Spec2kbakaneko2013/02/04 03:48 AM
                correct linksMichael S2013/02/04 05:10 AM
              spec95 vs Spec2kPatrick Chase2013/02/04 10:47 AM
                spec95 vs Spec2kPatrick Chase2013/02/04 10:55 AM
                  spec95 vs Spec2kMichael S2013/02/04 12:39 PM
                    spec95 vs Spec2kPatrick Chase2013/02/04 01:07 PM
                    spec95 vs Spec2knone2013/02/04 03:28 PM
                      spec95 vs Spec2kMichael S2013/02/05 01:35 AM
                spec95 vs Spec2kMichael S2013/02/04 12:50 PM
                spec95 vs Spec2k (hair-splitting)Kira2013/02/04 02:26 PM
    x86 penalty depends on performance and microarchitecturenone2013/02/02 04:33 AM
      x86 penalty depends on performance and microarchitecturePatrick Chase2013/02/02 09:11 AM
        x86 penalty depends on performance and microarchitecturenone2013/02/02 09:43 AM
          Cortex A9 ROBPatrick Chase2013/02/02 12:13 PM
            Cortex A9 ROBPatrick Chase2013/02/02 01:01 PM
              Cortex A9 ROBnone2013/02/04 03:12 PM
                Cortex A9 ROBPatrick Chase2013/02/04 03:43 PM
                  Cortex A9 ROBnone2013/02/04 03:58 PM
    ARM diversity might be an advantagePaul A. Clayton2013/02/02 10:10 AM
      ARM diversity might be an advantagePatrick Chase2013/02/03 03:29 PM
        ARMv8 cleanlinessanon2013/02/03 05:11 PM
          ARMv8 cleanlinessPatrick Chase2013/02/03 06:40 PM
            Does AArch64 not support table node page sizes?Paul A. Clayton2013/02/03 08:40 PM
              Does AArch64 not support table node page sizes?Patrick Chase2013/02/03 09:14 PM
                Does AArch64 not support table node page sizes?none2013/02/04 01:55 AM
              LPAE supports 2MiB and 1 GiB blocksPaul A. Clayton2013/02/03 09:52 PM
            ARMv8 cleanlinessanon2013/02/03 09:06 PM
              ARMv8 cleanlinessrwessel2013/02/03 11:37 PM
                ARMv8 cleanlinessMichael S2013/02/04 12:50 AM
              ARMv8 cleanlinessEtienne2013/02/04 07:01 AM
                Similar to Thumb If-Then instructionPaul A. Clayton2013/02/04 07:43 AM
                  Similar to Thumb If-Then instructionEtienne2013/02/05 06:22 AM
                ARMv8 cleanlinessJouni Osmala2013/02/04 10:15 PM
                  ARMv8 cleanlinessEtienne2013/02/05 05:57 AM
                    ARMv8 cleanlinessJouni Osmala2013/02/05 06:59 AM
                      ARMv8 cleanlinessEtienne2013/02/05 07:55 AM
              ARMv8 cleanlinessMaynard Handley2013/02/13 02:53 PM
                ARMv8 cleanlinessGabriele Svelto2013/02/14 12:37 AM
                ARMv8 cleanlinessEtienne2013/02/14 05:00 AM
                  ARMv8 cleanlinessrwessel2013/02/14 03:03 PM
                ARMv8 cleanlinessSeni2013/02/14 06:45 AM
                  ARMv8 cleanlinessrwessel2013/02/14 03:14 PM
                    ARMv8 cleanlinessLinus Torvalds2013/02/14 03:44 PM
                      ARMv8 cleanlinessGabriele Svelto2013/02/15 01:28 AM
                        ARMv8 cleanlinessEduardoS2013/02/15 09:45 AM
                        ARMv8 cleanlinessMax2013/02/15 12:24 PM
                          ARMv8 cleanlinessWilco2013/02/15 04:46 PM
                            ARMv8 cleanlinessLinus Torvalds2013/02/15 05:34 PM
                              ARMv8 cleanlinessWilco2013/02/17 12:47 PM
                                ARMv8 cleanlinessLinus Torvalds2013/02/17 03:08 PM
                                  ARMv8 cleanlinessWilco2013/02/18 04:14 PM
                                    ARMv8 cleanlinessanon2013/02/19 12:56 AM
                                      ARMv8 cleanlinessWilco2013/02/19 01:20 PM
                                    ARMv8 cleanlinessLinus Torvalds2013/02/19 09:13 AM
                                      ARMv8 cleanlinessWilco2013/02/19 01:10 PM
                                        ARMv8 cleanlinessLinus Torvalds2013/02/19 05:16 PM
                                          ARMv8 cleanlinessLinus Torvalds2013/02/19 05:41 PM
                                            ARMv8 cleanlinessWilco2013/02/25 05:05 AM
                                              ARMv8 cleanlinessLinus Torvalds2013/02/25 05:22 PM
                                                ARMv8 cleanlinessnone2013/02/26 12:31 AM
                                                  ARMv8 cleanlinessMichael S2013/02/26 04:05 AM
                                                ARMv8 cleanlinessDavid Hess2013/02/26 10:01 PM
                                                  ARMv8 cleanlinessLinus Torvalds2013/02/27 10:22 AM
                                                    ARMv8 cleanlinessDavid Hess2013/03/01 12:58 PM
                                                      What is wrong with ARM?Paul A. Clayton2013/03/01 05:56 PM
                                                        What is wrong with ARM?David Hess2013/03/01 06:49 PM
                                                          What is wrong with ARM?Michael S2013/03/02 04:11 PM
                                                            What is wrong with ARM?David Hess2013/03/03 10:32 PM
                                                              What is wrong with ARM?Michael S2013/03/04 01:05 AM
                                                        What is wrong with ARM?David Hess2013/03/07 05:30 PM
                                                          Thank you very much!Paul A. Clayton2013/03/07 06:59 PM
                                                            Thank you very much!David Hess2013/03/07 10:22 PM
                                                              Thank you very much!gallier22013/03/08 12:43 AM
                                                                Thank you very much!David Hess2013/03/08 10:24 AM
                                                                  Thank you very much!Ungo2013/03/08 03:37 PM
                                                                    Thank you very much!David Hess2013/03/08 07:47 PM
                                                            Thank you very much!Ricardo B2013/03/08 04:07 AM
                                                              ARM lackings a historical accident?Paul A. Clayton2013/03/08 07:54 AM
                                                                ARM lackings a historical accident?Ricardo B2013/03/08 02:33 PM
                                                          What is wrong with ARM?Michael S2013/03/08 05:25 AM
                                                            What is wrong with ARM?David Hess2013/03/08 11:37 AM
                                                            What is wrong with ARM?dmsc2013/03/12 02:47 PM
                                                          What is wrong with ARM?dmsc2013/03/12 02:43 PM
                                                      ARMv8 cleanlinessMichael S2013/03/02 04:06 PM
                                                    ParityAndi Kleen2013/03/03 12:47 PM
                                                      ParityLinus Torvalds2013/03/03 02:06 PM
                                                        ParityAndi Kleen2013/03/03 06:15 PM
                                            Except the borrow bitMatthew D2013/02/25 11:07 PM
                                              Except the borrow bitrwessel2013/02/25 11:42 PM
                                              Except the borrow bitLinus Torvalds2013/02/26 10:13 AM
                                                are ZSCO flags really fundamental?Michael S2013/02/27 03:24 PM
                                                  are ZSCO flags really fundamental?Linus Torvalds2013/02/27 04:41 PM
                                                    are ZSCO flags really fundamental?Michael S2013/02/28 12:39 AM
                                                    are ZSCO flags really fundamental?2013/03/01 09:23 AM
                                                  are ZSCO flags really fundamental?EduardoS2013/02/27 10:07 PM
                                                    are ZSCO flags really fundamental?Michael S2013/02/28 03:58 AM
                                                  are ZSCO flags really fundamental?rwessel2013/02/27 11:29 PM
                                                    are ZSCO flags really fundamental?rwessel2013/02/27 11:32 PM
                                                    Bit numbering on big endian machinesKonrad Schwarz2013/02/28 12:49 AM
                                                      Bit numbering on big endian machinesrwessel2013/02/28 01:32 AM
                                          ARMv8 cleanlinessWilco2013/02/25 04:54 AM
                                            ARMv8 cleanlinessEduardoS2013/02/25 05:24 AM
                                              ARMv8 cleanlinessWilco2013/02/25 06:36 AM
                                                ARMv8 cleanlinessEduardoS2013/02/25 12:06 PM
                                                  ARMv8 cleanlinessWilco2013/02/25 04:24 PM
                                                    ARMv8 cleanlinessEduardoS2013/02/25 04:55 PM
                                                    Utility of data loss exceptionsPaul A. Clayton2013/02/25 07:18 PM
                                                      Utility of data loss exceptionsrwessel2013/02/26 12:00 AM
                                                        Excessively expensive mode changingPaul A. Clayton2013/02/26 05:15 AM
                                                      Utility of data loss exceptionsEduardoS2013/02/26 01:55 AM
                                                        Utility of data loss exceptionsTREZA2013/02/26 03:53 AM
                                                          Utility of data loss exceptionsEduardoS2013/02/26 04:37 AM
                                                      Utility of data loss exceptionsEtienne2013/02/26 05:01 AM
                                            1b vs. 4b not a huge difference?Paul A. Clayton2013/02/25 08:57 AM
                                  Possible benefit of multi-bit CCPaul A. Clayton2013/02/23 07:09 AM
                                ARMv8 cleanlinessrwessel2013/02/17 11:01 PM
                                  ARMv8 cleanlinessWilco2013/02/18 04:33 PM
                                    ARMv8 cleanlinessEduardoS2013/02/18 07:18 PM
                                      ARMv8 cleanlinessWilco2013/02/25 05:19 AM
                      ARMv8 cleanlinessTREZA2013/02/15 03:21 AM
                      ARMv8 cleanliness2013/02/17 09:49 AM
                        ARMv8 cleanlinessLinus Torvalds2013/02/17 10:54 AM
                          ARMv8 cleanlinessLinus Torvalds2013/02/17 10:58 AM
                          ARMv8 cleanlinessnone2013/02/17 03:36 PM
                        ARMv8 cleanlinessTREZA2013/02/17 10:59 AM
                          ARMv8 cleanlinessWilco2013/02/17 11:30 AM
                            and-compare and or-comparePaul A. Clayton2013/02/17 04:28 PM
                              early branch resolutionanon2013/02/18 01:05 AM
                                My ignorance about compilers is vasterPaul A. Clayton2013/02/18 12:30 PM
                                early branch resolutionanon2013/02/18 04:12 PM
                              early branch resolution?EBFE2013/02/19 12:03 AM
                                Early resolution: some but limited potentialPaul A. Clayton2013/02/19 04:52 PM
                                  Early resolution: some but limited potentialhobold2013/02/20 01:02 PM
                                    PPC750 was an inspirationPaul A. Clayton2013/02/23 07:09 AM
                          ARMv8 cleanlinessTREZA2013/02/17 12:53 PM
                            ARMv8 cleanlinessExophase2013/02/17 03:49 PM
                        ARMv8 cleanlinessWilco2013/02/17 11:07 AM
                        ARMv8 cleanlinessbakaneko2013/02/17 11:43 AM
                        ARMv8 cleanlinessJouni Osmala2013/02/17 12:10 PM
                          -1 comparison true seems betterPaul A. Clayton2013/02/17 05:07 PM
                  ARMv8 cleanlinessEtienne2013/07/17 01:58 AM
      ARM server benchmark- why Apache?Per Hesselgren2013/02/04 11:13 PM
        ARM server benchmark- why Apache?anon2013/02/04 11:38 PM
          ARM server benchmark- why Apache?Per Hesselgren2013/02/05 12:25 AM
            ARM server benchmark- why Apache?Michael S2013/02/05 01:13 AM
          ARM server benchmark- why Apache?Michael S2013/02/05 12:51 AM
          I think that was debunked alreadyDavid Kanter2013/02/05 06:36 PM
        ARM server benchmark- why Apache?bakaneko2013/02/06 01:37 AM
          ARM server benchmark- why Apache?Michael S2013/02/06 02:43 AM
            Marketing to PHBs?Paul A. Clayton2013/02/06 05:40 AM
            ARM server benchmark- why Apache?bakaneko2013/02/06 06:08 AM
Reply to this Topic
Name:
Email:
Topic:
Body: No Text
How do you spell green?