Re: 2.2.18Pre Lan Performance Rocks!

From: Ingo Molnar (mingo@elte.hu)
Date: Tue Oct 31 2000 - 19:32:21 EST


On Tue, 31 Oct 2000, Jeff V. Merkey wrote:

> > One could create a 'kernel' that does:
> > for(;;)
> > {
> > proc0();
> > proc1();
> > proc2();
> > proc3();
> > etc();
> > }
>
> would be coded like this (no C compiler):
>
> proc0:
>
> proc1:
>
> proc2:
>
> proc3:
>
> etc:
>
> label:
> jmp proc0

oh, and what happens if it turns out that some other place wants to call
proc3 as well? Recode the assembly - cool! Not.

> I just avoided 5 x 20 bytes of pushes and pops on the stack ad optimized
> for a simple fall through case.

FYI, GCC does not generate 5 x 20 bytes of pushes and pops. In fact in the
above specific case it will not generate a single push (automatically -
you dont have to worry about it).

        Ingo

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