tree 8b7949376ec7bd0839f51072facdedc5bb89305d
parent 457042a4e0ddabd9824268336a1094ab9ab81dc3
author Nikita Popov <nikita.ppv@gmail.com> 1638026229 +0100
committer Copybara-Service <copybara-worker@google.com> 1638027767 -0800

[SCEV] Simplify invalidation after BE count calculation (NFCI)

After backedge taken counts have been calculated, we want to
invalidate all addrecs and dependent expressions in the loop,
because we might compute better results with the newly available
backedge taken counts. Previously this was done with a forgetLoop()
style use-def walk. With recent improvements to SCEV invalidation,
we can instead directly invalidate any SCEVs using addrecs in this
loop. This requires a great deal less subtlety to avoid invalidating
more than necessary, and in particular gets rid of the hack from
D113349. The change is similar to D114263 in spirit.

GitOrigin-RevId: c2550e342732d029c3a8ae1eff764d68b1abfc59