On Thu, Apr 25, 2013 at 10:32 PM, Johan Tibell <[email protected]>wrote:

> If you remember where it would be great to see an example.
>

I'm afraid I don't remember. I spend a lot of time optimising things down
to the last memory allocation, and this was one of those cases where I
could keep heap allocation constant by unboxing an unpacked field
repeatedly, whereas if I packed the field I was allocating a little on
every iteration of whatever the loop was.


> There's also NOUNPACK nowadays so you can opt out in these specific cases.
>

Oh yes, I have no problem with this becoming the default behaviour. All I
was doing was confirming that it is not always a win "in the wild".
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