[llvm] [AMDGPU] Restrict promote alloca on pointers across address spaces (PR #119762)

[Matt Arsenault via llvm-commits]

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@@ -198,3 +167,39 @@ entry:
   %tmp = load ptr addrspace(3), ptr addrspace(5) %alloca, align 8
   ret ptr addrspace(3) %tmp
 }
+
+; Will not vectorize because we are doing a load/store of a pointer across
+; address spaces of varying pointer sizes.
+define ptr @alloca_load_store_ptr64_full_ivec(ptr %arg) {
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arsenm wrote:

This is just a regression, there's no reason this can't be handled 

https://github.com/llvm/llvm-project/pull/119762