std.range.zip performance

[spir]

On 02/16/2011 03:36 AM, Andrei Alexandrescu wrote:
> Initial: 58 seconds.
>
> Eliminated the switch in popFront: 53s.
>
> Replaced emplace with assignment: 23s.
>
> Specialized emplace for non-struct types, reinserted: 23s.
>
> Eliminated the loop in empty (replaced with return ranges[0].empty;): 17s.
>
> I'm sure there are ways to further improve this, but there are a few
> difficulties. Each pass through the loop the code must transport values from
> the two arrays into a specific format and then distribute them for further
> calculation. Then, upon each popFront two words must be touched because arrays
> hold pointer+length, not pointer+pointer (as probably would be better since
> ranges are around).
>
>
> Nice analysis!

Bearophile, is clay's zip func lazy. Else, it could explain part of its 
performance, don't you think?

Denis