Hi,
On Sun, 2 Mar 2003, Ulrich Drepper wrote:
> > - if (!urb->status & !acm->throttle) {
> > + if (!urb->status && !acm->throttle) {
>
> [...]
>
> Observe the extra 'jne' and the fact that the value of 'throttle'
> element cannot be loaded until after the conditional jump. Not even
> out of order execution can arrange that.
But speculative execution can arrange that (providing the cpu predicted
the jump target correctly).
> To summarize, I'd probably not be amused if you would change any of my
> code which takes advantage of such programming finess.
If that was really intentional, I would assume to see something like this:
if (!(urb->status | acm->throttle)) {
bye, Roman
-
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This archive was generated by hypermail 2b29 : Fri Mar 07 2003 - 22:00:18 EST