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Author: ylzsx

llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp

@@ -2585,6 +2585,11 @@ SDValue DAGTypeLegalizer::PromoteIntOp_ExpOp(SDNode *N) {
                              : RTLIB::getLDEXP(N->getValueType(0));
 
   if (LC == RTLIB::UNKNOWN_LIBCALL || !TLI.getLibcallName(LC)) {
+    // Scalarize vector FPOWI instead of promoting the type. This allows the
+    // scalar FPOWIs to be visited and converted to libcalls before promoting
+    // the type.
+    // FIXME: This should be done in LegalizeVectorOps/LegalizeDAG, but call
+    // lowering needs the unpromoted EVT.
     if (IsPowI && N->getValueType(0).isVector())
       return DAG.UnrollVectorOp(N);
     SmallVector<SDValue, 3> NewOps(N->ops());