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

[via llvm-commits]

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@@ -8647,13 +8647,17 @@ static MapVector<PHINode *, VPValue *> collectUsersInExitBlock(
   // from scalar loop only.
   if (MiddleVPBB->getNumSuccessors() != 2)
     return {};
-  MapVector<PHINode *, VPValue *> ExitingValuesToFix;
-  BasicBlock *ExitBB =
-      cast<VPIRBasicBlock>(MiddleVPBB->getSuccessors()[0])->getIRBasicBlock();
+  MapVector<VPIRInstruction *, VPValue *> ExitingValuesToFix;
+  VPBasicBlock *ExitVPBB = cast<VPIRBasicBlock>(MiddleVPBB->getSuccessors()[0]);
   BasicBlock *ExitingBB = OrigLoop->getExitingBlock();
-  for (PHINode &ExitPhi : ExitBB->phis()) {
-    Value *IncomingValue =
-        ExitPhi.getIncomingValueForBlock(ExitingBB);
+  for (VPRecipeBase &R : *ExitVPBB) {
+    auto *IR = dyn_cast<VPIRInstruction>(&R);
+    if (!IR)
+      continue;
+    auto *ExitPhi = dyn_cast<PHINode>(&IR->getInstruction());
+    if (!ExitPhi)
+      break;
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ayalz wrote:

Breaking because all remaining recipes are expected to be non phi's? Should the lcssa VPIRI's be considered phi recipes (as do loop header phi recipes) to help ensure they appear before non-phi recipes (VPIRI's) in the VP(IR)BB?

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