Revert "[DAGCombiner] Add vector demanded elements support to computeKnownBits"
This seems to have increased LTO compile time bejond 2x of previous builds.
Do you have any more details you can give me on the regressions? A repro would be best, otherwise I'm just going to be poking in the dark on this one..... Looking through the build server logs there seems to be plenty of other times where this buildbot takes a lot longer to build, sometimes for a single build other times for many.
This might have been really unfortunate timing. We added a few faster machines, which screwed with the timeout calculation (which is based on the previous builds). We changed the job to only build on the faster machines now.
Sorry about that. Please land your change again.