------- Comment #4 from rakdver at atrey dot karlin dot mff dot cuni dot cz 2007-03-26 18:00 ------- Subject: Re: [4.3 Regression] rtl loop invariant is broken
> > I guess the cost of loading zero is cheaper then? > > Cheaper than loading 0xDEADBEEF but not cheap enough not to pull out of the > loop. All the "easy" (one instruction) constants are not pulled out. > > Really I think rtl loop invariant should pull everything it can pull out of > the > loop and then let the RA "fix" up the loop when it runs out of registers. I would agree, if we had RA capable of that (which I am not quite sure whether we do or not, although this seems simple enough), or better, RA doing better job under high register pressure. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=31360
