Hi! Please Cc: me on combine patches; you sent it nine days ago, and I didn't see it until now.
On Wed, Mar 04, 2020 at 08:39:36AM +0000, Yangfei (Felix) wrote: > This is a simple fix for PR94026. > With this fix, combine will try make an extraction if we are in a equality > comparison and this is an AND > with a constant which is power of two minus one. Shift here should be an > constant. For example, combine > will transform (compare (and (lshiftrt x 8) 6) 0) to (compare (zero_extract > (x 2 9)) 0). Why is that a good thing? (There should be thorough tests on many archs, showing it helps on average, and it doesn't regress anything. I can do that for you, but not right now). The code needs more comments, and the commit message should say what is done and why you made those choices. In general, we should have *fewer* zero_extract, not more. Segher
