[llvm] [X86][GlobalISel] Use GIntrinsic during custom intrinsic selection (PR #83498)

[Matt Arsenault via llvm-commits]

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@@ -1843,7 +1843,7 @@ bool X86InstructionSelector::selectIntrinsicWSideEffects(
   assert(I.getOpcode() == TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS &&
          "unexpected instruction");
 
-  if (I.getOperand(0).getIntrinsicID() != Intrinsic::trap)
+  if (cast<GIntrinsic>(I).getIntrinsicID() != Intrinsic::trap)
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arsenm wrote:

generic intrinsics should not use G_INTRINSIC, this shouldn't have been reachable 

https://github.com/llvm/llvm-project/pull/83498