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    SubjectRe: [PATCH] Multiple & vs. && and | vs. || bugs in 2.4.20
    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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