[llvm] [VPlan] Introduce explicit ExtractFromEnd recipes for live-outs. (PR #100658)

[via llvm-commits]

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@@ -8452,7 +8452,104 @@ static void addUsersInExitBlock(
            return P && Inductions.contains(P);
          })))
       continue;
-    Plan.addLiveOut(&ExitPhi, V);
+
+    auto MiddleVPBB =
+        cast<VPBasicBlock>(Plan.getVectorLoopRegion()->getSingleSuccessor());
+    VPBuilder B(MiddleVPBB);
+    if (auto *Terminator = MiddleVPBB->getTerminator()) {
+      auto *Condition = dyn_cast<VPInstruction>(Terminator->getOperand(0));
+      assert((!Condition || Condition->getParent() == MiddleVPBB) &&
+             "Condition expected in MiddleVPBB");
+      B.setInsertPoint(Condition ? Condition : Terminator);
+    }
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ayalz wrote:

Can B be set once, before entering the loop over ExitBB's phis?

https://github.com/llvm/llvm-project/pull/100658