[llvm] [RFC] IR: Define noalias.addrspace metadata (PR #102461)

[Rahul Joshi via llvm-commits]

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@@ -8021,6 +8021,43 @@ it will contain a list of ids, including the ids of the callsites in the
 full inline sequence, in order from the leaf-most call's id to the outermost
 inlined call.
 
+
+'``noalias.addrspace``' Metadata
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The ``noalias.addrspace`` metadata is used to identify memory
+operations which cannot access a range of address spaces. It is
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jurahul wrote:

Will/can alias analysis be extended to look at this and infer NoAlias/NoModRef where appropriate? I was thinking something like `AddressSpaceNoAliasAA` similar to `ScopeNoAliasAA` can be added to the default AA pipeline.

https://github.com/llvm/llvm-project/pull/102461