[llvm] 15770a1 - [VPlan] Remove dead recipes in entry when merging regions. (NFC)

[Florian Hahn via llvm-commits]

Author: Florian Hahn
Date: 2025-03-04T08:26:27Z
New Revision: 15770a1e9d0983ee59a8850f2ddd7b57e46dcc5a

URL: https://github.com/llvm/llvm-project/commit/15770a1e9d0983ee59a8850f2ddd7b57e46dcc5a
DIFF: https://github.com/llvm/llvm-project/commit/15770a1e9d0983ee59a8850f2ddd7b57e46dcc5a.diff

LOG: [VPlan] Remove dead recipes in entry when merging regions. (NFC)

Also remove recipes in the entry of the region that will be removed.
This makes sure we don't leave any dead users around. NFC at the moment,
but avoids causing issues in the future.

Added: 
    

Modified: 
    llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp b/llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp
index 3d1de68c83747..6944bfcb5352b 100644
--- a/llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp
+++ b/llvm/lib/Transforms/Vectorize/VPlanTransforms.cpp
@@ -290,6 +290,11 @@ static bool mergeReplicateRegionsIntoSuccessors(VPlan &Plan) {
       Phi1ToMove.moveBefore(*Merge2, Merge2->begin());
     }
 
+    // Remove the dead recipes in Region1's entry block.
+    for (VPRecipeBase &R :
+         make_early_inc_range(reverse(*Region1->getEntryBasicBlock())))
+      R.eraseFromParent();
+
     // Finally, remove the first region.
     for (VPBlockBase *Pred : make_early_inc_range(Region1->getPredecessors())) {
       VPBlockUtils::disconnectBlocks(Pred, Region1);