[TargetLowering][PowerPC] Don't unroll vector CLMUL when MUL is not supported. (#184238)

We can use the bittest lowering instead.
2026-03-03 17:25:54 -08:00 · 2026-03-03 17:25:54 -08:00 · 98c46261d9
commit 98c46261d9
parent 1c434928d2
2 changed files with 2338 additions and 2213 deletions
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@ -8464,10 +8464,6 @@ SDValue TargetLowering::expandCLMUL(SDNode *Node, SelectionDAG &DAG) const {
  unsigned BW = VT.getScalarSizeInBits();
  unsigned Opcode = Node->getOpcode();

-  // Scalarize if the vector multiplication is unlikely to work.
-  if (VT.isVector() && !isOperationLegalOrCustom(ISD::MUL, VT))
-    return DAG.UnrollVectorOp(Node);
-
  switch (Opcode) {
  case ISD::CLMUL: {
    // NOTE: If you change this expansion, please update the cost model
--- a/llvm/test/CodeGen/PowerPC/clmul-vector.ll
+++ b/llvm/test/CodeGen/PowerPC/clmul-vector.ll