On Sat, Jun 29, 2002 at 03:55:39PM -0400, Diego Novillo wrote:
On Sat, 29 Jun 2002, Aldy Hernandez wrote:
what's the slowness factor in the compiler now?
Bootstrap times are roughly 2x. Yes, it's disgraceful.
have you benchmarked this to find out where most of the time is being
spent?
is it in the simplification or in the ssa building? or both?
are we running ssa on the simplified trees only? are we doing the
ssa-on-rtl thing as well?
hmmmm, this seems like something worth looking into. i doubt anyone's
going to be too inclined to use these optimizations if there's a 2X
slowdown.
perhaps when we start disabling rtl optimizers and replacing them with
simple-tree optimizers we can see an increase in speed? or at least
a decrease that's not as bad :)
now that we have everything simpliable for C, perhaps we can implement
one entire optimization pass (constant propagation or PRE ?) entirely
on trees and disable the rtl counterparts. that should give us an idea
of how bad things are going to look ;-).