[MLIR][Python] Expose the insertion point of pattern rewriter (#161001)

In [#160520](https://github.com/llvm/llvm-project/pull/160520), we
discussed the current limitations of PDL rewriting in Python (see [this
comment](https://github.com/llvm/llvm-project/pull/160520#issuecomment-3332326184)).
At the moment, we cannot create new operations in PDL native (python)
rewrite functions because the `PatternRewriter` APIs are not exposed.

This PR introduces bindings to retrieve the insertion point of the
`PatternRewriter`, enabling users to create new operations within Python
rewrite functions. With this capability, more complex rewrites e.g. with
branching and loops that involve op creations become possible.

---------

Co-authored-by: Maksim Levental <maksim.levental@gmail.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/mlir/lib/Bindings/Python/IRModule.h b/mlir/lib/Bindings/Python/IRModule.h
index edbd73e..e706be3b 100644
--- a/mlir/lib/Bindings/Python/IRModule.h
+++ b/mlir/lib/Bindings/Python/IRModule.h
@@ -841,6 +841,8 @@ public:
   PyInsertionPoint(const PyBlock &block);
   /// Creates an insertion point positioned before a reference operation.
   PyInsertionPoint(PyOperationBase &beforeOperationBase);
+  /// Creates an insertion point positioned before a reference operation.
+  PyInsertionPoint(PyOperationRef beforeOperationRef);
 
   /// Shortcut to create an insertion point at the beginning of the block.
   static PyInsertionPoint atBlockBegin(PyBlock &block);