From: bjl@loki.pttrnl.nl (Ben Lippolt) Subject: Re: tlA: /bin/arch solved. Date: Sun, 26 Jul 1992 06:44:13 GMT
as@prg.ox.ac.uk (Andrew Stevens) writes:
>In article <bjl.711923672@freyr> B.J.Lippolt@research.ptt.nl writes:
>>Is there a way to distinguish between a 386 and a 486? I have a 486,
>>but 'uname -m' says 'i386'. But when I compile with 'gcc -m486' I'll
>>get code which doesn't run on a 386.
>Surely this is not the case. As I understood it the user-level instruction
>sets of the 386 and 486 are identical. The -m486 flag just tweaks
>code generation to use instruction sequences better suited to the 486's
>instruction timings instead of sequences best suited to 386 instruction
>timings.
Thanks for your explanation. I was under the impression that the 486 had
some extra instructions which the 386 didn't had.
Does this mean that if I compile with -m486 and run the code on a 386 it
will be slightly less efficient than without -m486?
Ben Lippolt