Re: cloning a basic type efficiently

"Mathias Gaunard" wrote


Thanks for the typo and style corrections - some of which were new to me -
and some were because I must have been asleep! (New was the fact that the
existence of a user defined constructor only blocks the compiler making a
copy constructor if one of the user constructors is a copy constructor.)

However, my main concern is performance - At least on g++ and VS2003/5 and
on a very tight loop - I get a 10 times speed down when not using the
native
types. On bigger loops I still get a factor of 3-4 speed up by not using
the
classes. I would have hoped for identical code. Perhaps there is a way of
achieving this and I am still getting some subtle thing wrong that forces
compilers to write intermediate results to memory instead of using
registers
etc. Changing the references to calls by value also has no significant
effect.