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Re: [patch,libgfortran] PR48298 DTIO implementation for Internal Units
On Wed, Sep 14, 2016 at 08:46:00AM -0700, Jerry DeLisle wrote:
>
> Well so much for my hopes. I have done some large loop tests with two strings
> inside the loop. One is KIND=1 and one is KIND=4.
>
> I see a 15% slowdown. My guess is its in the treap search and stack overhead.
>
I suspect you'll find that the slowdown will depend
on what you are writing into the string. Try formatting
a REAL(16), which is a software 128-bit floating implementation.
IMHO, a working, complete, implementation of DTIO is worth
any slowdown. Someone worried about speed can try to
optimize/change the nascent stack algorithm.
Knuth: "We should forget about small efficiencies, say about 97%
of the time: premature optimization is the root of all evil. Yetr
we should not pass up our opportunities in that critical 3%"
Or http://c2.com/cgi/wiki?MakeItWorkMakeItRightMakeItFast
--
Steve