------- Comment #2 from bonzini at gnu dot org 2009-04-16 08:04 ------- Subject: Re: [cond-optab] CSE does not put subregs into COMPAREs on many CC0 machines
> Is this a cond-optab regression or "just" an observation? Yes, it causes extra moves on code using unions. Where we have r20:SI=r19:SF#0 where X#0 = (subreg X 0) cc0=r20:SI is now r20:SI=r19:SF#0 cc0=cmp(r20:SI,0) and CSE is somehow not able to turn it into cc0=cmp(r19:SF#0,0) -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=39717
