[LV] Explicitly disable in-loop reductions for AnyOf and FindIV. nfc (#163541)

Currently, in-loop reductions for AnyOf and FindIV are not supported.
They were implicitly blocked. This happened because
RecurrenceDescriptor::getReductionOpChain could not detect their
recurrence chain. The reason is that RecurrenceDescriptor::getOpcode was
set to Instruction::Or, but the recurrence chains of AnyOf and FindIV do
not actually contain an Instruction::Or.

This patch explicitly disables in-loop reductions for AnyOf and FindIV
instead of relying on getReductionOpChain to implicitly prevent them.

1 files changed, 6 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 9f0d6fcb237e..58fcab40d589 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -6591,9 +6591,14 @@ void LoopVectorizationCostModel::collectInLoopReductions() {
     if (RdxDesc.getRecurrenceType() != Phi->getType())
       continue;
 
+    // In-loop AnyOf and FindIV reductions are not yet supported.
+    RecurKind Kind = RdxDesc.getRecurrenceKind();
+    if (RecurrenceDescriptor::isAnyOfRecurrenceKind(Kind) ||
+        RecurrenceDescriptor::isFindIVRecurrenceKind(Kind))
+      continue;
+
     // If the target would prefer this reduction to happen "in-loop", then we
     // want to record it as such.
-    RecurKind Kind = RdxDesc.getRecurrenceKind();
     if (!PreferInLoopReductions && !useOrderedReductions(RdxDesc) &&
         !TTI.preferInLoopReduction(Kind, Phi->getType()))
       continue;