Gaetano Mendola <[EMAIL PROTECTED]> writes:
[ use list with master node and circular linking ]
now is very late here ( 04:17 AM ) so I wrote the wrong code ( not checked ) but show the idea of avoid "if".
This saves an "if" during addition of a list item, at the cost of greater expense during list traversal. (Instead of a loop termination test like "ptr != NULL", you need something like "ptr != master_node". This may not take an extra cycle, but only if you can afford to dedicate a register to holding the value of master_node within the loop. That hurts, especially on architectures with not very many registers.)
Well, if the same architecture have not so many register I guess don't have a double prefetch instruction queue and an "if" branch will hurt/destroy that queue, am I wrong ?
I'm going to post on comp.lang.c++.moderated and comp.std.c++ in order to have better argumentations
Anyway, we should build the code that way and then do profiling with and without support for constant-cost length().
I totally agree with you.
Regards Gaetano Mendola
---------------------------(end of broadcast)--------------------------- TIP 2: you can get off all lists at once with the unregister command (send "unregister YourEmailAddressHere" to [EMAIL PROTECTED])
