space profiling

[Stephen Weeks]

> I  just  realized that the space profiling is definitely going to have a real
> problem with overflowing the bins.  If I have a hot loop allocating  lots  of
> junk,  it  isn't  hard  for one location to be responsible for more than 2^32
> bytes of allocation. 

I agree.

> This seems like another  argument  for  going  for  the
> procedure call, and having the linked list use 64 bits worth of counter (plus
> 32 bits for the link).  This way you are safe from wrapping.

Couldn't we just go to 64 bit bins?