Far and near pointers on the 80286 and later
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From: Jonathan de Boyne Pollard on 22 Mar 2010 06:09 > > > I have detested the old x86 segmented architecture for about three > decades. > Where "about" is "less than", given the release year of the 80286? (-: >> x86_64 doesn't even support segmentation. >> > And good riddance!!! What took them so long?! :-) > Trying to do things the "right" way (as I suspect many people in this thread would label it) with IA64 and having most of the world (possibly also including many people in this thread) ignore the results. (-:
From: Bill Davidsen on 22 Mar 2010 12:09 Jonathan de Boyne Pollard wrote: >> >> >> I have detested the old x86 segmented architecture for about three >> decades. >> > Where "about" is "less than", given the release year of the 80286? (-: > >>> x86_64 doesn't even support segmentation. >>> >> And good riddance!!! What took them so long?! :-) >> > Trying to do things the "right" way (as I suspect many people in this > thread would label it) with IA64 and having most of the world (possibly > also including many people in this thread) ignore the results. (-: > These quotes must be from posts missed or expired on the system I use, what was the "x86_64 doesn't even support segmentation" in reference to, or is this confusion between x86_64 and ia64 support, or ???
From: Scott Lurndal on 22 Mar 2010 15:06 Jonathan de Boyne Pollard <J.deBoynePollard-newsgroups(a)NTLWorld.COM> writes: >> >> >> I have detested the old x86 segmented architecture for about three >> decades. >> >Where "about" is "less than", given the release year of the 80286? (-: > >>> x86_64 doesn't even support segmentation. >>> >> And good riddance!!! What took them so long?! :-) >> >Trying to do things the "right" way (as I suspect many people in this >thread would label it) with IA64 and having most of the world (possibly >also including many people in this thread) ignore the results. (-: > No. AMD designed the 64-bit extensions, not Intel. So IA64 had nothing to do with it. And segmentation hasn't been used by any production operating system on ia32 since the 386; made perfect sense for AMD to dump it in 64-bit modes. scott
From: Jonathan de Boyne Pollard on 22 Mar 2010 18:04 > >>>> >>>> x86_64 doesn't even support segmentation. >>>> >>> And good riddance!!! What took them so long?! :-) >>> >> Trying to do things the "right" way (as I suspect many people in this >> thread would label it) with IA64 and having most of the world >> (possibly also including many people in this thread) ignore the >> results. (-: >> > No. AMD designed the 64-bit extensions, not Intel. So IA64 had nothing > to do with it. > You make the point for me, would you but realize it. Intel was spending its time and effort doing things the "right" way, which is why it took "so long" for x86-64 to become widespread across the board. > And segmentation hasn't been used by any production operating system > on ia32 since the 386; [...] > Untrue. It has been used on all of them. In addition to the obvious requirements at the systems programming level, some of them permit (or even require!) applications softwares to know of it. Multithreaded applications programming on 32-bit OS/2 and (x86) Win32 can involve the explicit use of the FS register by applications softwares, for example.
From: Seebs on 22 Mar 2010 19:09
On 2010-03-22, Jonathan de Boyne Pollard <J.deBoynePollard-newsgroups(a)NTLWorld.COM> wrote: > You make the point for me, would you but realize it. Intel was spending > its time and effort doing things the "right" way, which is why it took > "so long" for x86-64 to become widespread across the board. Time from first distribution of x86-64 to at least two major vendors shipping parts in large quantities: ??? Time from first distribution of IA64 to at least two major vendors shipping parts in large quantities: ??? I wouldn't say that x86-64 took long to become widespread, compared with IA64. I'm also not at all sure that IA64 counts as doing things the "right" way. So far, the largest impact I've seen from IA64 is that it's increased confusion because people keep thinking it means x86-64. > Untrue. It has been used on all of them. In addition to the obvious > requirements at the systems programming level, some of them permit (or > even require!) applications softwares to know of it. Multithreaded > applications programming on 32-bit OS/2 and (x86) Win32 can involve the > explicit use of the FS register by applications softwares, for example. I was not aware of any remaining uses of the segmented address space stuff in modern BSD or Linux on x86. So far as I can tell, they jump into the flat memory model and stay there. -s -- Copyright 2010, all wrongs reversed. Peter Seebach / usenet-nospam(a)seebs.net http://www.seebs.net/log/ <-- lawsuits, religion, and funny pictures http://en.wikipedia.org/wiki/Fair_Game_(Scientology) <-- get educated! |