vendor/llvm-project/llvmorg-15.0.0-rc2-40-gfbd2950d8d0d

1 files changed, 13 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 238b074089aa..91bc7dbad1d0 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -10109,8 +10109,19 @@ bool LoopVectorizePass::processLoop(Loop *L) {
     if (Hints.getForce() == LoopVectorizeHints::FK_Enabled)
       LLVM_DEBUG(dbgs() << " But vectorizing was explicitly forced.\n");
     else {
-      LLVM_DEBUG(dbgs() << "\n");
-      SEL = CM_ScalarEpilogueNotAllowedLowTripLoop;
+      if (*ExpectedTC > TTI->getMinTripCountTailFoldingThreshold()) {
+        LLVM_DEBUG(dbgs() << "\n");
+        SEL = CM_ScalarEpilogueNotAllowedLowTripLoop;
+      } else {
+        LLVM_DEBUG(dbgs() << " But the target considers the trip count too "
+                             "small to consider vectorizing.\n");
+        reportVectorizationFailure(
+            "The trip count is below the minial threshold value.",
+            "loop trip count is too low, avoiding vectorization",
+            "LowTripCount", ORE, L);
+        Hints.emitRemarkWithHints();
+        return false;
+      }
     }
   }