Question about BITSET_WORD

Hi,

I'm new to this list, so sorry if it is not the correct place.

I've started to looked at the source code of mesa and I wonder why in 
src/util/bitset.h we have:

     #define BITSET_WORD unsigned int

This is as-is since at least 2015, probably 2011.

Would it make sense to have it as a long, at least on 64 bits arch?
(the linux kernel uses bitmaps as unsigned long)

I don't think that it should be a noticeable speed-up, but at least on 
Linux it could save some cycles when doing some OR or AND and co on 
bitmaps on a 64 bits cpu.

Just my 2c.

Christophe JAILLET