[llvm] Intrinsic: introduce minimumnum and maximumnum for IR and SelectionDAG (PR #96649)

[Matt Arsenault via llvm-commits]

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@@ -8531,6 +8531,70 @@ SDValue TargetLowering::expandFMINIMUM_FMAXIMUM(SDNode *N,
   return MinMax;
 }
 
+SDValue TargetLowering::expandFMINIMUMNUM_FMAXIMUMNUM(SDNode *Node,
+                                                      SelectionDAG &DAG) const {
+  SDLoc dl(Node);
+  unsigned NewOp = Node->getOpcode() == ISD::FMINIMUMNUM ? ISD::FMINNUM_IEEE
+                                                         : ISD::FMAXNUM_IEEE;
+  EVT VT = Node->getValueType(0);
+
+  if (VT.isScalableVector())
+    report_fatal_error(
+        "Expanding fminimumnum/fmaximumnum for scalable vectors is undefined.");
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arsenm wrote:

It's not undefined. But I don't see how scalable vectors are relevant here. The code should work as-is, this just needs to use the same type for every operation 

https://github.com/llvm/llvm-project/pull/96649