[llvm] [DirectX] only allow intrinsics defined in DXIL.td (PR #128613)

[Farzon Lotfi via llvm-commits]

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@@ -770,8 +770,14 @@ class OpLowerer {
         continue;
       Intrinsic::ID ID = F.getIntrinsicID();
       switch (ID) {
-      default:
+      case Intrinsic::dx_resource_casthandle:
+      case Intrinsic::not_intrinsic:
         continue;
+      default: {
+        DiagnosticInfoUnsupported Diag(F, "Unknown intrinsic?");
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farzonl wrote:

The intrinsic name seems to already be encoded this is the error string i see `function llvm.vector.reduce.and.v4i32 i32 (<4 x i32>): Unknown intrinsic?`

https://github.com/llvm/llvm-project/pull/128613