[llvm] [IR][RFC] Add @llvm.mask.beforefirst intrinsic (PR #203874)

[Luke Lau via llvm-commits]

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@@ -6767,6 +6767,11 @@ void Verifier::visitIntrinsicCall(Intrinsic::ID ID, CallBase &Call) {
           "get_active_lane_mask: element type is not i1", Call);
     break;
   }
+  case Intrinsic::mask_beforefirst: {
+    Check(Call.getType()->getScalarType()->isIntegerTy(1),
+          "mask.beforefirst element type must be i1", Call);
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lukel97 wrote:

I believe that's already covered by the `llvm_anyvector_ty` declaration in Intrinsics.td, any non-vector type already gets rejected

https://github.com/llvm/llvm-project/pull/203874