[llvm] [LV][EVL] Support in-loop reduction using tail folding with EVL. (PR #90184)

[Mel Chen via llvm-commits]

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@@ -1611,6 +1648,29 @@ void VPReductionRecipe::print(raw_ostream &O, const Twine &Indent,
     O << " (with final reduction value stored in invariant address sank "
          "outside of loop)";
 }
+
+void VPReductionEVLRecipe::print(raw_ostream &O, const Twine &Indent,
+                                 VPSlotTracker &SlotTracker) const {
+  O << Indent << "REDUCE ";
+  printAsOperand(O, SlotTracker);
+  O << " = ";
+  getChainOp()->printAsOperand(O, SlotTracker);
+  O << " +";
+  if (isa<FPMathOperator>(getUnderlyingInstr()))
+    O << getUnderlyingInstr()->getFastMathFlags();
+  O << " reduce." << Instruction::getOpcodeName(RdxDesc.getOpcode()) << " (";
+  getVecOp()->printAsOperand(O, SlotTracker);
+  O << ", ";
+  getEVL()->printAsOperand(O, SlotTracker);
+  if (getCondOp()) {
+    O << ", ";
+    getCondOp()->printAsOperand(O, SlotTracker);
+  }
+  O << ")";
+  if (RdxDesc.IntermediateStore)
+    O << " (with final reduction value stored in invariant address sank "
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Mel-Chen wrote:

f1c0f9338ca9bca68ba02efb01ca44550c64e375

https://github.com/llvm/llvm-project/pull/90184