[llvm] [VPlan] Add VPIRInstruction, use for exit block live-outs. (PR #100735)

[via llvm-commits]

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@@ -8695,17 +8698,18 @@ addUsersInExitBlock(VPlan &Plan,
   }
 
   // Introduce VPUsers modeling the exit values.
-  for (const auto &[ExitPhi, V] : ExitingValuesToFix) {
+  for (const auto &[IR, V] : ExitingValuesToFix) {
     // Pass live-in values used by exit phis directly through to the live-out.
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ayalz wrote:

Phi's in exit block that are fed by live-in values which bypass the original loop, seem redundant - should they be considered lcssa phi's? Can be checked later, independently.

https://github.com/llvm/llvm-project/pull/100735