[fpc-devel] I'll be straight

Marģers . margers.roked at inbox.lv
Sat Feb 9 13:42:33 CET 2019

fillchar is one useful function, but should be
avoided from use in time critical code by any
cost. Only reasonable way to improve fillchar is
to make it internal function, where fpc can
decide, depending on parameters, what will be best
solution for filling mem with specified value. But
it  will also slow down compilation time. Not sure
fpc core team will accept that kind improvement.

Optimized code for speed most likely became less
readable and less maintainable. It's misfortune of

----- Reply to message -----
Subject: Re: [fpc-devel] I'll be straight
Date: 2019. gada 9. februāris 10:35:51
From:  J. Gareth Moreton <gareth at moreton-family.com>
To:  FPC developers' list
<fpc-devel at lists.freepascal.org>
> Thanks Michael,

> In the last patch that Jonas almost immediately
closed, the speed savings were inconclusive
because the number of cycles saved is probably
only a few dozen, but I would argue it makes the
code a bit more reasonable too because it replaces
things like loc[low(loc)] with loc[0] and fillchar
with a for-loop that initialises each element of
an array to zero (it's slightly faster because the
element size is a multiple of 16, while fillchar
is general-purpose and spends a lot of time
jumping around and even performing a
multiplication before it starts filling things
up).  I guess seeing it marked as "won't fix"
within 20 minutes was a moment of horror.

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