Re: Structure vs purism ?

Harald Wagener (hollow@Informatik.Uni-Bremen.DE)
21 Jan 1999 18:50:39 +0100


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...

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