"Thomas F. Burdick" <[EMAIL PROTECTED]> writes: > Changing the type declaration for POS1 to (INTEGER 1 1000) and POS2 to > (INTEGER 1000 1000000) gives a 10% speedup on the Sun I'm working on. > *But*, the usefulness of precise type declarations shines when you > change the OPTIMIZE SAFETY declaration to 1. The version with FIXNUM > declarations experiences a 37% slowdown, whereas the version with > precise declarations stays the same: meaning that, at SAFETY=1, the > version with precise type declarations runs at 67% the speed of the > FIXNUM version. > > At SAFETY=0, I don't know what precise type declarations will buy you > on an architecture designed by drunken monkies, but I'd still give it > a try.
It helps at safety=1, but, as you suspected, little or nothing at safety=0. The disassembly for the innermost loop is slightly shorter (five instead of six instructions for the floating point addition). Nicolas.
