[AArch64] getCopyFromPartsVector "Cannot narrow, it would be a lossy transformation" assertion lowering a `<3 x float>` argument

Live Reproducer: https://godbolt.org/z/h115oeY4s

Compiling the following LLVM IR with llc asserts Assertion ... "Cannot narrow, it would be a lossy transformation" in getCopyFromPartsVector.
The trigger is a function whose ninth vector argument is <3 x float> and is returned directly.

target triple = "aarch64-unknown-linux-gnu"

define <3 x float> @repro(<3 x i32> %a0, <3 x i32> %a1, <3 x i32> %a2,
                           <3 x i32> %a3, <3 x i32> %a4, <3 x i32> %a5,
                           <3 x i32> %a6, <3 x i32> %a7, <3 x float> %a8) {
  ret <3 x float> %a8
}

llc command:

llc repro.ll

Error output:

llc: /root/llvm-project/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:423:
llvm::SDValue getCopyFromPartsVector(llvm::SelectionDAG&, const llvm::SDLoc&, const llvm::SDValue*, unsigned int, llvm::MVT, llvm::EVT, const llvm::Value*, llvm::SDValue, std::optional<unsigned int>):
Assertion `(PartEVT.getVectorElementCount().getKnownMinValue() > ValueVT.getVectorElementCount().getKnownMinValue())
           && (PartEVT.getVectorElementCount().isScalable() == ValueVT.getVectorElementCount().isScalable())
           && "Cannot narrow, it would be a lossy transformation"' failed.