[llvm] 791523b - [LV] Set loop metadata after VPlan execution (NFC).

[Florian Hahn via llvm-commits]

Author: Florian Hahn
Date: 2022-01-03T09:59:50Z
New Revision: 791523bae6153b13bb41ba05c9fc89e502cc4a1a

URL: https://github.com/llvm/llvm-project/commit/791523bae6153b13bb41ba05c9fc89e502cc4a1a
DIFF: https://github.com/llvm/llvm-project/commit/791523bae6153b13bb41ba05c9fc89e502cc4a1a.diff

LOG: [LV] Set loop metadata after VPlan execution (NFC).

Setting the loop metadata for the vector loop after VPlan execution
allows generating the full loop body during VPlan execution. This is in
preparation for D113224.

Added: 
    

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

Removed: 
    


################################################################################
diff  --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index bb5691842111..a277ee37d12c 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -3547,25 +3547,6 @@ BasicBlock *InnerLoopVectorizer::completeLoopSkeleton(Loop *L,
          "Inconsistent vector loop preheader");
   Builder.SetInsertPoint(&*LoopVectorBody->getFirstInsertionPt());
 
-  Optional<MDNode *> VectorizedLoopID =
-      makeFollowupLoopID(OrigLoopID, {LLVMLoopVectorizeFollowupAll,
-                                      LLVMLoopVectorizeFollowupVectorized});
-  if (VectorizedLoopID.hasValue()) {
-    L->setLoopID(VectorizedLoopID.getValue());
-
-    // Do not setAlreadyVectorized if loop attributes have been defined
-    // explicitly.
-    return LoopVectorPreHeader;
-  }
-
-  // Keep all loop hints from the original loop on the vector loop (we'll
-  // replace the vectorizer-specific hints below).
-  if (MDNode *LID = OrigLoop->getLoopID())
-    L->setLoopID(LID);
-
-  LoopVectorizeHints Hints(L, true, *ORE, TTI);
-  Hints.setAlreadyVectorized();
-
 #ifdef EXPENSIVE_CHECKS
   assert(DT->verify(DominatorTree::VerificationLevel::Fast));
   LI->verify(*DT);
@@ -7971,6 +7952,27 @@ void LoopVectorizationPlanner::executePlan(ElementCount BestVF, unsigned BestUF,
   BestVPlan.prepareToExecute(ILV.getOrCreateTripCount(nullptr), State);
   BestVPlan.execute(&State);
 
+  // Keep all loop hints from the original loop on the vector loop (we'll
+  // replace the vectorizer-specific hints below).
+  MDNode *OrigLoopID = OrigLoop->getLoopID();
+
+  Optional<MDNode *> VectorizedLoopID =
+      makeFollowupLoopID(OrigLoopID, {LLVMLoopVectorizeFollowupAll,
+                                      LLVMLoopVectorizeFollowupVectorized});
+
+  Loop *L = LI->getLoopFor(State.CFG.PrevBB);
+  if (VectorizedLoopID.hasValue())
+    L->setLoopID(VectorizedLoopID.getValue());
+  else {
+    // Keep all loop hints from the original loop on the vector loop (we'll
+    // replace the vectorizer-specific hints below).
+    if (MDNode *LID = OrigLoop->getLoopID())
+      L->setLoopID(LID);
+
+    LoopVectorizeHints Hints(L, true, *ORE);
+    Hints.setAlreadyVectorized();
+  }
+
   // 3. Fix the vectorized code: take care of header phi's, live-outs,
   //    predication, updating analyses.
   ILV.fixVectorizedLoop(State);