[llvm] [AMDGPU] New test for untested line in AMDGPUMarkLastScratchLoad (PR #185430)

[via llvm-commits]

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@@ -279,3 +279,308 @@ define amdgpu_cs void @max_11_vgprs_branch(ptr addrspace(1) %p, i32 %tmp) "amdgp
   store volatile i32 %v10, ptr addrspace(1) poison
   ret void
 }
+
+
+declare i32 @foo() nounwind
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ambergorzynski wrote:

I added `nounwind` in response to [this comment](https://github.com/llvm/llvm-project/pull/185430#discussion_r2907045520) - did I add it incorrectly or do you think it's unnecessary for the whole test?

https://github.com/llvm/llvm-project/pull/185430