[llvm] [mlir] [AMDGPU][Verifier] Check address space of `alloca` instruction (PR #135820)

[Shilei Tian via llvm-commits]

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@@ -4395,6 +4395,11 @@ void Verifier::visitAllocaInst(AllocaInst &AI) {
     verifySwiftErrorValue(&AI);
   }
 
+  if (TT.isAMDGPU()) {
+    Check(AI.getAddressSpace() == AMDGPUAS::PRIVATE_ADDRESS,
+          "alloca on amdgpu must be in addrspace(5)", &AI);
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shiltian wrote:

> I think llc and opt do default to the correct data layout based on triple nowadays, but it's possible llvm-as doesn't do this, as a low level tool.

Yes, `llvm-as` does not. In the previous version where I used DL, I did have to add a `A5` data layout to the test case of the command line.

https://github.com/llvm/llvm-project/pull/135820