[clang] [CIR] Add assume_separate_storage operation (PR #149696)

[Henrich Lauko via cfe-commits]

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@@ -3004,6 +3004,26 @@ def CIR_AssumeOp : CIR_Op<"assume"> {
   }];
 }
 
+def CIR_AssumeSepStorageOp : CIR_Op<"assume_separate_storage",
+                                    [SameTypeOperands]> {
+  let summary =
+      "Tell the optimizer that two pointers point to different allocations";
+  let description = [{
+    The `cir.assume.separate_storage` operation takes two pointers as arguments,
----------------
xlauko wrote:

```suggestion
    The `cir.assume_separate_storage` operation takes two pointers as arguments,
```

https://github.com/llvm/llvm-project/pull/149696