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Re: [perl #76438] peephole optimiser could prune more dead code

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Leon Timmermans
July 10, 2010 16:25
Re: [perl #76438] peephole optimiser could prune more dead code
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On Sat, Jul 10, 2010 at 9:16 PM, Ben Morrow <> wrote:
> Quoth (Leon Timmermans):
> Most of those forms of magic don't have meaningful side-effects, though,
> at least on mg_get. (That is, they may have side-effects, but it doesn't
> matter if they aren't invoked. Tainting is the obvious exception.) This
> is what really matters from the pov of optimisation.

If you're only ignoring get magic and not set magic, I guess it's
possible if you special-case special variables with get magic such as
$!. @_ elements should probably also be exempt or else passing a tied
argument will break very confusingly. I'm not entirely sure what the
consequences of ignoring substr, pos and $#array and autovivication
get magic. I suspect they'll work in the common case, but will break
in corner cases.


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