[llvm] [AArch64] Add @llvm.experimental.vector.match (PR #101974)

[Ricardo Jesus via llvm-commits]

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@@ -8137,6 +8137,42 @@ void SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I,
              DAG.getNode(ISD::EXTRACT_SUBVECTOR, sdl, ResultVT, Vec, Index));
     return;
   }
+  case Intrinsic::experimental_vector_match: {
+    SDValue Op1 = getValue(I.getOperand(0));
+    SDValue Op2 = getValue(I.getOperand(1));
+    SDValue Mask = getValue(I.getOperand(2));
+    EVT Op1VT = Op1.getValueType();
+    EVT Op2VT = Op2.getValueType();
+    EVT ResVT = Mask.getValueType();
+    unsigned SearchSize = Op2VT.getVectorNumElements();
+
+    LLVMContext &Ctx = *DAG.getContext();
+    const auto &TTI =
+        TLI.getTargetMachine().getTargetTransformInfo(*I.getFunction());
+
+    // If the target has native support for this vector match operation, lower
+    // the intrinsic directly; otherwise, lower it below.
+    if (TTI.hasVectorMatch(cast<VectorType>(Op1VT.getTypeForEVT(Ctx)),
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rj-jesus wrote:

Yep, exactly, that was my rationale. I was thinking of using the intrinsic from LoopIdiomVectorize, so I thought the TTI hook would be the least intrusive method. Do you think it's worth adding a cost model either way?

https://github.com/llvm/llvm-project/pull/101974