Re: tags in the 3 lowest bits

[Stefan Monnier]

> We could wrap malloc and free on such systems to force 8 byte alignment like
> this  (it's a little costly in memory, but no big deal):

The cost is zero for cons cells and floats (which are already wrapped to
ensure alignment, for other reasons), it's negligible for strings, markers,
and symbols, but it's a bit heavy for small arrays.

OTOH, small arrays are already inefficient (because each array, no matter
how small, is added to the memory-map (a binary tree) used for conservative
stack marking).  So maybe we should begin by changing the handling of small
arrays (similar to what is done for strings, although I'm not quite sure
what it would look like).


        Stefan