Re: any chance of 2.6.0-test*?

[Oliver Neukum <oliver _at_ xxxxxxxxxxx>]

Am Montag, 13. Januar 2003 00:11 schrieb Rob Wilkens:
> On Sun, 2003-01-12 at 17:52, Aaron Lehmann wrote:
> > On Sun, Jan 12, 2003 at 05:34:58PM -0500, Rob Wilkens wrote:
> > > You're wrong.  You wouldn't have to jump over them any more than you
> > > have to jump over the "goto" statement.
> >
> > The goto is a conditional jump. You propose replacing it with a
> > conditional jump past the error handling code predicated on the
> > opposite condition. Where's the improvement?
>
> The goto is absolutely not a conditional jump.  The if that precedes it
> is conditional.  The goto is not.  The if is already there.

Oh, well.
Apologies first, my assembler is rusty.

if (a == NULL)
	goto err_out;

bad compiler ->
tst $D0 ; evaluate a == NULL
bne L1 ; this is the if
bra err_out ; this is the goto
L1:

good compiler ->
tst $D0
beq err_out ; obvious optimisation

	Oliver

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