[llvm] [NVPTX] Check Before inserting AddrSpaceCastInst in NVPTXLoweringAlloca (PR #106127)

[Artem Belevich via llvm-commits]

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@@ -17,7 +17,21 @@ define void @kernel() {
   ret void
 }
 
+define void @alloc_already_in_addrspace5() {
+; LABEL: @lower_alloca_addrspace5
+; PTX-LABEL: .visible .func alloc_already_in_addrspace5(
+  %A = alloca i32, addrspace(5)
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Artem-B wrote:

The test is OK. Extra comments are helpful, but it's even better if the test is self-documenting. 
E.g. renaming the test above to `alloca_in_explicit_local_as` would do the trick.

https://github.com/llvm/llvm-project/pull/106127