Latest experiments...happiness and sadness

[David Chase]

On 2012-10-16, at 8:53 PM, Charles Oliver Nutter <headius at headius.com> wrote:
> 
> So *almost* everything is inlining, but one path (I believe it's the
> failure path from GWT after talking with Christian) is not reached.
> Because Hotspot's EA can't do partial EA, any unfollowed paths that
> would receive the allocated object have to be considered escapes, and
> so anywhere we're doing guarded logic (either in indy or in Java code,
> like Fixnum overflow checks) the unfollowed paths prevent EA from
> happening. Boo-hoo.

> Thoughts?

I'm very new to this (have not even looked at the source code to Hotspot yet), but is it possible
to push the allocation/boxing to paths that are believed to be rarely taken?  This is not unlike
region-based register allocation, where register allocation is limited to what are believe to be
the hot regions, and worry about region exits later -- if necessary, you can always spill there. 

David