[llvm] [Attributor] Add support for atomic operations in `AAAddressSpace` (PR #106927)

[Matt Arsenault via llvm-commits]

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@@ -86,3 +86,163 @@ define void @call_volatile_load_store_as_4(ptr addrspace(4) %p1, ptr addrspace(4
   call void @volatile_load_store_as_1(ptr %p2.cast)
   ret void
 }
+
+define internal void @can_infer_cmpxchg(ptr %word) {
+; CHECK-LABEL: define internal void @can_infer_cmpxchg(
+; CHECK-SAME: ptr [[WORD:%.*]]) #[[ATTR0:[0-9]+]] {
+; CHECK-NEXT:    [[TMP1:%.*]] = addrspacecast ptr [[WORD]] to ptr addrspace(1)
+; CHECK-NEXT:    [[CMPXCHG_0:%.*]] = cmpxchg ptr addrspace(1) [[TMP1]], i32 0, i32 4 monotonic monotonic, align 4
+; CHECK-NEXT:    [[TMP2:%.*]] = addrspacecast ptr [[WORD]] to ptr addrspace(1)
+; CHECK-NEXT:    [[CMPXCHG_1:%.*]] = cmpxchg ptr addrspace(1) [[TMP2]], i32 0, i32 5 acq_rel monotonic, align 4
+; CHECK-NEXT:    [[TMP3:%.*]] = addrspacecast ptr [[WORD]] to ptr addrspace(1)
+; CHECK-NEXT:    [[CMPXCHG_2:%.*]] = cmpxchg ptr addrspace(1) [[TMP3]], i32 0, i32 6 acquire monotonic, align 4
+; CHECK-NEXT:    [[TMP4:%.*]] = addrspacecast ptr [[WORD]] to ptr addrspace(1)
+; CHECK-NEXT:    [[CMPXCHG_3:%.*]] = cmpxchg ptr addrspace(1) [[TMP4]], i32 0, i32 7 release monotonic, align 4
+; CHECK-NEXT:    [[TMP5:%.*]] = addrspacecast ptr [[WORD]] to ptr addrspace(1)
+; CHECK-NEXT:    [[CMPXCHG_4:%.*]] = cmpxchg ptr addrspace(1) [[TMP5]], i32 0, i32 8 seq_cst monotonic, align 4
+; CHECK-NEXT:    [[TMP6:%.*]] = addrspacecast ptr [[WORD]] to ptr addrspace(1)
+; CHECK-NEXT:    [[CMPXCHG_5:%.*]] = cmpxchg weak ptr addrspace(1) [[TMP6]], i32 0, i32 9 seq_cst monotonic, align 4
+; CHECK-NEXT:    [[TMP7:%.*]] = addrspacecast ptr [[WORD]] to ptr addrspace(1)
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arsenm wrote:

It's not ideal this ends up creating the same addrspacecast for every instance 

https://github.com/llvm/llvm-project/pull/106927