DOS ain't dead

PCI phased out? (Announce)

posted by Rugxulo , Usono, 21.02.2011, 07:15

> >>> You don't need extra registers (use push/pop).
>
> >> Slower since less pipelinable than non stalling reg operations. And the
> >> more regs, the more unnecessary stalls can be avoid.
>
> > Slower? Barely (if at all). Push/pop has been fast, esp. since Pentium
> (two
> > in one clock). How many free registers is enough, 16? 256? 512? 1024?
>
> Actually, these cycle counts are misleading, PUSH/POP effective lag will be
> dominated by access times to the memory hierarchy, which are much higher
> than CPU cycles - even to/from L1 cache, where the stack top will likely
> find its place. Thus when there is pressure on the general registers, PUSH
> reg/POP reg will incur significant performance penalties and is not a free
> substitute for more CPU registers

I disagree. We may like more registers, but that's not realistic or else they would've done so by now. I hate to always bring up the past, but if we (and "real" pros) lived without it all these years, it can't be that unbearable.

> I find appalling that AMD/Intel did not build a way, be it awkward, to
> access the enlarged 64-bit registers in X86 mode, which would have been so
> immediately useful unlike the address size extensions that few
> people require. I'm sure you could easily think of ways to enhance the X86
> binary operation encoding to allow for 64 bit operations on the 8 legacy
> registers, and hardly less easily allow access to the new ones (R8->R15),
> maybe not all at the same time, all that with minimal compatibility
> problems in 32 bit mode. But no, they didn't even try ! Drat!

Perhaps they considered MMX/SSE as a workaround, who knows.

Complete thread:

• PCI phased out? - marcov, 09.02.2011, 12:51 (Announce)
  • PCI phased out? - RayeR, 09.02.2011, 16:24
    • PCI phased out? - marcov, 10.02.2011, 16:02
      • PCI phased out? - RayeR, 10.02.2011, 17:57
        • PCI phased out? - marcov, 10.02.2011, 21:10
          • PCI phased out? - RayeR, 11.02.2011, 00:25
            • PCI phased out? - marcov, 11.02.2011, 10:56
              • PCI phased out? - RayeR, 12.02.2011, 02:34
                • PCI phased out? - marcov, 12.02.2011, 12:45
                  • PCI phased out? - Rugxulo, 12.02.2011, 21:28
                    • PCI phased out? - DOS386, 13.02.2011, 06:02
                      • PCI phased out? - RayeR, 13.02.2011, 16:11
                        • PCI phased out? - DOS386, 14.02.2011, 09:27
                    • PCI phased out? - marcov, 14.02.2011, 10:29
                    • NTVDM speed (or lack thereof) - Ninho, 15.02.2011, 12:26
                      • NTVDM speed (or lack thereof) - Rugxulo, 15.02.2011, 14:26
                        • NTVDM speed (or lack thereof) - marcov, 15.02.2011, 14:33
                        • NTVDM speed (or lack thereof) - Ninho, 15.02.2011, 20:27
                          • NTVDM speed (or lack thereof) - Rugxulo, 15.02.2011, 23:21
                            • NTVDM speed (or lack thereof) - marcov, 16.02.2011, 09:24
                            • NTVDM speed (or lack thereof) - Ninho, 16.02.2011, 20:04
                          • NTVDM speed (or lack thereof) - RayeR, 16.02.2011, 01:50
                            • NTVDM speed (or lack thereof) - Rugxulo, 16.02.2011, 02:24
                              • NTVDM speed (or lack thereof) - RayeR, 16.02.2011, 10:41
                              • NTVDM speed (or lack thereof) - rr, 17.02.2011, 20:33
                  • PCI phased out? - RayeR, 14.02.2011, 15:45
                    • PCI phased out? - marcov, 15.02.2011, 13:40
                      • PCI phased out? - RayeR, 15.02.2011, 15:15
                        • PCI phased out? - marcov, 15.02.2011, 18:43
                          • PCI phased out? - RayeR, 15.02.2011, 19:46
                            • PCI phased out? - marcov, 16.02.2011, 10:36
                              • PCI phased out? - RayeR, 16.02.2011, 12:22
                                • PCI phased out? - marcov, 16.02.2011, 15:38
                                  • PCI phased out? - Rugxulo, 16.02.2011, 19:18
                                    • PCI phased out? - marcov, 16.02.2011, 21:22
                                      • PCI phased out? - Rugxulo, 17.02.2011, 02:28
                                        • EOD (was "PCI phased out?") - DOS386, 17.02.2011, 06:44
                                        • PCI phased out? - marcov, 17.02.2011, 19:44
                                          • PCI phased out? - Rugxulo, 18.02.2011, 08:39
                                            • PCI phased out? - marcov, 18.02.2011, 09:30
                                              • PCI phased out? - Rugxulo, 21.02.2011, 07:43
                                              • PCI phased out? - Rugxulo, 08.03.2011, 23:47
                                                • PCI phased out? - Rugxulo, 11.03.2011, 00:06
                                                  • PCI phased out? - roytam, 11.03.2011, 07:52
                                                • PCI phased out? - Rugxulo, 17.03.2011, 04:16
                                            • PCI phased out? - Ninho, 19.02.2011, 10:56
                                              • PCI phased out? - Rugxulo, 21.02.2011, 07:15
                                                • PCI phased out? - marcov, 21.02.2011, 14:09
                                                  • PCI phased out? - Laaca, 21.02.2011, 14:22
                                        • PCI phased out? - marcov, 21.02.2011, 14:47
                                          • PCI phased out? - roytam, 22.02.2011, 04:26
                                            • PCI phased out? - RayeR, 22.02.2011, 13:29
                                            • PCI phased out? - RayeR, 22.02.2011, 23:44
                                              • PCI phased out? - Ninho, 23.02.2011, 17:39
                                                • PCI phased out? - RayeR, 23.02.2011, 19:47
                                                  • PCI phased out? - Ninho, 23.02.2011, 19:56
                                                    • PCI phased out? - RayeR, 23.02.2011, 23:27
                                                    • PCI phased out? - RayeR, 24.02.2011, 14:37
                                          • PCI phased out? - Rugxulo, 16.03.2011, 04:58
                                  • PCI phased out? - RayeR, 18.02.2011, 14:28
                                    • PCI phased out? - marcov, 18.02.2011, 14:56
                        • PCI phased out? - roytam, 29.01.2015, 03:45