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    SubjectRe: Structure vs purism ?


    On 21 Jan 1999, Harald Wagener wrote:

    > Helge Hafting <helge.hafting@daldata.no> writes:
    >
    > >
    > >
    > > [...]
    > > > Just under 1000 goto's. Some of which are trivial. Goto's to one-liners,
    > > > which are easily tidied. Other files are real snakes-nests. Following the
    > > > trail of goto's as they double back on themselves is no fun for the brain,
    > > > even less so for a CPU, as modern features such as branch prediction are
    > > > misused. (Remember the branch prediction tables are a set size, and can
    > > > only store results of a few jumps).
    > >
    > > As far as I know - no branch prediction is invoked for a goto,
    > > because the jump is unconditional - and fast.
    > >
    > > Tidying up is generally a good thing, but make sure you don't
    > > ruin any "fast-path" optimizations by doing so.
    > > (That's where the common code path is a small place that fits in
    > > the cpu cache, while all exceptional cases are treated elsewhere. Goto's
    > > might be useful for doing that.
    >
    > Another thing is that _sometimes_ gotos are an elegant way to impelemt
    > transaction protocol lookalikes without too much fuzz...

    State machines are far more easily implemented using gotos, and I
    expect that this is another valid use for gotos in Linux.


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