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

[Shilei Tian via llvm-commits]

================
@@ -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
----------------
shiltian wrote:

`nounwind` is not needed

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