Performance comparison

[Andrew Haley]

Jeff Sturm writes:
 > On Mon, 29 Jul 2002, Andrew Haley wrote:
 > > I'm sure that's the main reason.  Once we get global inlining working
 > > I expect to see a decent improvement.
 > 
 > Provided that increased register pressure doesn't ruin the benefits of
 > inlining.

I'm thinking of the many small methods that don't increase register
pressure at all.  The x86 is a nightmare in this regard, I grant you,
so it may not benefit so much.

 > The new register allocator may help, too.

 > It'd be nice to have a study on the effects of inlining real-world code
 > with GCC on multiple targets.  I haven't seen any, and chances are any
 > that already exist are obsolete anyway.  Meanwhile I've noticed a lot more
 > hand-waving arguments than real numbers.

Certainly the numbers I've seen for targets with deep pipelines (+
lotsa registers + speculation) suggest that global inlining can be a
very good thing.

Andrew.