https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62173
--- Comment #19 from Ramana Radhakrishnan <ramana at gcc dot gnu.org> --- (In reply to Richard Biener from comment #18) > It's probably not correct to simply transfer range info from *idx to > iv->base. > Instead SCEV analysis needs to track the range of CHREC_LEFT when it analyzes > the SSA use-def chain. That's of course a much bigger change :/ > > The patch may still help in some cases - I suppose the original testcase is > reduced from sth else? Not sure if this is related to comment #c2 where the reference is to a 15% regression in bzip2 compress at O3. Sebastian could probably confirm. I don't think we can ignore the regression though, can we ? regards Ramana
