llvm-project

edb690dc - Reapply "[VPlan] Add canonical IV during construction (NFC)."

Reapply "[VPlan] Add canonical IV during construction (NFC)." This reverts commit d431921677ae923d189ff2d6f188f676a2964ed8. Missing gtests have been updated. Original message: This addresses an existing TODO and simply moves the current code to add canonical IV recipes to the initial skeleton construction, at the same place where the corresponding region will be introduced.