[llvm] Attributor: Infer noalias.addrspace metadata for memory instructions (PR #136553)

[Shilei Tian via llvm-commits]

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@@ -12786,6 +12788,193 @@ struct AAAddressSpaceCallSiteArgument final : AAAddressSpaceImpl {
 };
 } // namespace
 
+/// ------------------------ No Alias Address Space  ---------------------------
+// This attribute assumes flat address space can alias all other address space
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shiltian wrote:

Honestly, I think this and AAAddressSpace's impl class can be merged such that one impl class can serve two AAs. Can you try and see that is feasible? I'd say 80% of the code is similar.

https://github.com/llvm/llvm-project/pull/136553