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| From | Bartc <bc@freeuk.com> |
|---|---|
| Newsgroups | comp.lang.c |
| Subject | Re: no stack |
| Date | 2015-03-22 12:16 +0000 |
| Organization | A noiseless patient Spider |
| Message-ID | <membpv$4na$1@dont-email.me> (permalink) |
| References | <347790b0-5f11-4008-b254-5b5d5229a387@googlegroups.com> <mem82b$o3u$1@dont-email.me> <b118532f-fcb7-4c44-9394-4706316f3fbd@googlegroups.com> |
On 22/03/2015 11:46, fir wrote: > >>> 3) smaller >> >> Not really. Now each access to a local variable needs a 32 or 64-bit >> absolute address, instead of an 8-bit offset. Plus you need static >> memory space for all the local variables of *all* functions in the >> application at the same time, whether or not they are active. >> > there would be needed ram for all okal variables stored as static but this is no > big amout i think, how many you could have it in average 100klines program, > few thousands of ints/floats probably > (of mostly uninitialised ram) > > probably you will got some spare of code on all those pushes and pops/stack pointer manipulations > > as to offset when storing locals as statick you could also use 8 bit offset > why no, you could also use it probably more than in stack version, as you probably could offset all args/variables in whole program with say 16 bit offset > as this is completely static An 8-bit offset to what? Some sort of global static-local data register that now needs preserving across external function calls? Or something that is loaded on entry to each function? Plus, a 16-bit offset might not be possible (I think x86 offers 8-bit or 32-bit offsets). Also, you might be forgetting about local structs and arrays, which may take up a lot of space (remember this might be all the local variables of 1000 functions). Of course you might be right and everyone else is wrong. But since compilers generally don't work like this, you'd have to do something yourself. (I strongly suspect that if using static locals was faster, then gcc would do just that. Perhaps it does.) >> You've got that back to front. Having local variables on a stack is more >> versatile. > > in what way? i didnt see it.. static adressing is imo much simpler (also less > confusing for programmers - though probably it will bring some important changes in the sea worth rethinking (disasembly would look different etc)) I don't understand your point. What machine addressing is being used is of no concern to someone coding in C. If they're worried, then that can manually use 'static' for locals if they wish. But this is wrong: 'static' shouldn't be used an an optimisation tool, but for data that is persistent. And have two kinds of functions - recursive and non-recursive - itself introduces extra complexity. -- bartc
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no stack fir <profesor.fir@gmail.com> - 2015-03-22 02:09 -0700
Re: no stack wssimms@gmail.com - 2015-03-22 02:52 -0700
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 03:04 -0700
Re: no stack Richard Heathfield <rjh@cpax.org.uk> - 2015-03-22 13:15 +0000
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 07:37 -0700
Re: no stack Lőrinczy Zsigmond <nospam@for.me> - 2015-03-22 11:10 +0100
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 03:30 -0700
Re: no stack jacob navia <jacob@jacob.remcomp.fr> - 2015-03-22 11:15 +0100
Re: no stack jacob navia <jacob@jacob.remcomp.fr> - 2015-03-22 11:23 +0100
Re: no stack jacob navia <jacob@jacob.remcomp.fr> - 2015-03-22 11:24 +0100
Re: no stack jacob navia <jacob@jacob.remcomp.fr> - 2015-03-22 11:41 +0100
Re: no stack Keith Thompson <kst-u@mib.org> - 2015-03-22 12:18 -0700
Re: no stack Melzzzzz <mel@zzzzz.com> - 2015-03-22 20:25 +0100
Re: no stack Stephen Sprunk <stephen@sprunk.org> - 2015-03-23 12:17 -0500
Re: no stack James Kuyper <jameskuyper@verizon.net> - 2015-03-23 13:22 -0400
Re: no stack Bartc <bc@freeuk.com> - 2015-03-22 11:13 +0000
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 04:29 -0700
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 04:33 -0700
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 04:39 -0700
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 04:46 -0700
Re: no stack Bartc <bc@freeuk.com> - 2015-03-22 12:16 +0000
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 05:25 -0700
Re: no stack Bartc <bc@freeuk.com> - 2015-03-22 12:59 +0000
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 07:15 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-22 15:39 +0100
Re: no stack Bartc <bc@freeuk.com> - 2015-03-22 19:47 +0000
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-23 02:18 -0700
Re: no stack Bartc <bc@freeuk.com> - 2015-03-23 11:21 +0000
Re: no stack Richard Heathfield <rjh@cpax.org.uk> - 2015-03-23 11:35 +0000
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-23 07:07 -0700
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-23 07:28 -0700
Re: no stack Bartc <bc@freeuk.com> - 2015-03-23 14:56 +0000
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-23 08:13 -0700
Re: no stack Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-03-22 13:01 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-23 13:14 +0100
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 05:30 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-22 14:15 +0100
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 04:49 -0700
Re: no stack Melzzzzz <mel@zzzzz.com> - 2015-03-22 12:37 +0100
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 05:06 -0700
Re: no stack Melzzzzz <mel@zzzzz.com> - 2015-03-22 13:23 +0100
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 05:48 -0700
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 08:51 -0700
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-23 07:39 -0700
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-23 07:54 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-22 14:45 +0100
Re: no stack Richard Heathfield <rjh@cpax.org.uk> - 2015-03-22 14:20 +0000
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-22 15:43 +0100
Re: no stack Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-03-22 13:09 -0700
Re: no stack Bartc <bc@freeuk.com> - 2015-03-22 20:38 +0000
Re: no stack Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-03-22 13:54 -0700
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-23 02:08 -0700
Re: no stack Ben Bacarisse <ben.usenet@bsb.me.uk> - 2015-03-23 12:07 +0000
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-23 07:13 -0700
Re: no stack Kaz Kylheku <kaz@kylheku.com> - 2015-03-22 20:59 +0000
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 07:35 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-22 16:27 +0100
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-22 05:10 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-22 13:56 +0100
Re: no stack John Bode <jfbode1029@gmail.com> - 2015-03-24 09:01 -0700
Re: no stack Keith Thompson <kst-u@mib.org> - 2015-03-24 12:30 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-25 09:16 +0100
Re: no stack Tim Rentsch <txr@alumni.caltech.edu> - 2015-03-25 09:00 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-25 17:33 +0100
Re: no stack James Kuyper <jameskuyper@verizon.net> - 2015-03-25 13:35 -0400
Re: no stack Tim Rentsch <txr@alumni.caltech.edu> - 2015-03-25 16:22 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-26 08:54 +0100
Re: no stack Keith Thompson <kst-u@mib.org> - 2015-03-26 08:48 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-26 23:00 +0100
Re: no stack Tim Rentsch <txr@alumni.caltech.edu> - 2015-03-28 09:15 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-28 18:17 +0100
Re: no stack Malcolm McLean <malcolm.mclean5@btinternet.com> - 2015-03-28 12:36 -0700
Re: no stack Richard Damon <Richard@Damon-Family.org> - 2015-03-28 17:33 -0400
Re: no stack Tim Rentsch <txr@alumni.caltech.edu> - 2015-03-30 08:04 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-04-07 00:39 +0200
Re: no stack fir <profesor.fir@gmail.com> - 2015-03-26 01:21 -0700
Re: no stack Keith Thompson <kst-u@mib.org> - 2015-03-25 10:57 -0700
Re: no stack David Brown <david.brown@hesbynett.no> - 2015-03-25 21:55 +0100
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