------- Comment #25 from dnovillo at redhat dot com 2006-11-09 17:38 ------- Subject: Re: [4.3 Regression] Misscompilation of spec2006 gcc
Daniel Berlin wrote on 11/09/06 12:22: > Right, but the difference is, In the scheme i propose, you'd never > have overlapping live ranges of vuse/vdefs, and in mem-ssa, you do. > IE we wouldn't run into all the problems mem-ssa is going to bring in > this regard. No, that's not right. Overlapping live-ranges are not a problem until you hit a PHI node. That's where currently mem-ssa is having difficulties with. We can use those static partitions at key points during SSA renaming. Since the partitions are completely unrelated to the renamer, we can experiment with different partitioning schemes. It's actually even possible to arrive to a perfect partitioning scheme that doesn't introduce false positive dependencies. More details to follow. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29680
