[llvm] [mlir][bufferization] Don't clone on unknown ownership and verify function boundary ABI (PR #66626)

[Martin Erhart via llvm-commits]

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@@ -55,8 +55,38 @@ def BufferDeallocationOpInterface :
           ownership indicator when needed, it should be implemented using this
           method (which is especially important if operations are created that
           cannot be easily canonicalized away anymore).
+          Ownership indicators have to be materialized when
+            * needed for the condition operands of a `bufferization.dealloc` op
+            * passed along MemRefs to successor blocks via additional forwarded
+              operands of terminator ops
+            * passing them as additional operands to nested regions (e.g.,
+              init_args of `scf.for`)
+            * passing them as additional operands to a call operation when
+              `private-function-dynamic-ownership` is enabled
+            * a copy is made conditionally on the current ownership, etc.
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maerhart wrote:

I meant 'copy' when I wrote it, but then removed the cloning, so it's outdated now. Will remove this BP.

https://github.com/llvm/llvm-project/pull/66626