> pardon silly question, but... why, on 64bit machine, P9 uses 32bit ints and
> longs?
>
> my impression is, int was supposed to match machine's preferred (best
> performance etc.) integeral datatype, and long was supposed to be enough to
> hold a pointer? (i.e., sizeof(long) >= sizeof(void*))
charles could provide a more complete answer, but
http://en.wikipedia.org/wiki/C_data_types
is a good summary of the general rules. long is only
>= 32 bits. there are no other restrictions. it does
not have to be big enough to hold a pointer.
while the original idea for int was that it was the natural
word size, things are no longer quite that simple. int
must be >= 16 bits, so if you were to do c on, say, a
15 bit machine, int would need to be simulated to be
standard, but i doubt anyone would bother slaving to
the standard so.
and on a x86_64 what is the "natural size" of an integer?
since it's not risc, there is no penalty for doing 32-bit calcuations.
heck, the docs call a 4-byte integer a "double word" and
an 8-byte integer a "quad word". i suppose you could make
an argument for 16-bit int on intel!
- erik
