At Tue, 27 Sep 2005 12:00:09 +1000, Bruce Badger wrote:
> On 9/27/05, Erik de Castro Lopo <[EMAIL PROTECTED]> wrote:
> > There are large classes of problems where running speed is an
> > important issue. Static typing does make for faster run times
> > and in cases where that moves your program from being too
> > slow to being fast enough, that is not a premature optimisation.
> 
> Modern VMs (e.g. many of the Smalltalk VMs) dynamically compile code,
> i.e. they JIT.  
[...]
> In fact, the very best of the JITing VMs can get performance that
> exceeds that attainable by static compilation - because there is
> more information available at run time to base the tuning decisions
> upon.

If a program's use changes over its invocation, and the JIT
continually shifts its optimisation targets, then I can see the
potential benefit of this approach.  I don't believe, however, that
there are many programs that have this dynamic behaviour.

You can gain the same runtime knowledge in a statically compiled C
program by compiling with gcc's -ffprofile-arcs, running over some
typical use cases (will write a bunch of .gcda files) and then
recompiling with -fbranch-probabilities.

-- 
 - Gus
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