[llvm] [InferAddressSpaces] collect flat address expression from return value (PR #70610)

[Matt Arsenault via llvm-commits]

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@@ -4,10 +4,9 @@
 ;  this doesn't do something insane on non-canonical IR.
 
 ; CHECK-LABEL: @return_select_group_flat(
-; CHECK-NEXT: %cast0 = addrspacecast ptr addrspace(3) %group.ptr.0 to ptr
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arsenm wrote:

I think this also should check the signature of the function; need to make sure you aren't mutating it in a way that breaks uses 

https://github.com/llvm/llvm-project/pull/70610