[PyCDE] Import MLIR: provide hook to preprocess ops

[teqdruid]

Adds the ability for users to load the MLIR file and preprocess pre-lowering ops.

[Copilot]

Pull Request Overview

This PR adds a hook to System.import_mlir allowing users to preprocess or skip MLIR operations before lowering.
Key changes:

• Introduce a preprocess_op callback parameter in import_mlir
• Update the import loop to apply preprocess_op and skip None results
• Extend the existing test to verify skipping an extern module via preprocess_op

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
frontends/PyCDE/test/test_import_hw_modules.py	Remove unused IrModule import and add a preprocess_op test
frontends/PyCDE/src/pycde/system.py	Add preprocess_op parameter to import_mlir signature and implement preprocessing logic

Comments suppressed due to low confidence (1)

frontends/PyCDE/test/test_import_hw_modules.py:65

• The test references sys.argv but sys is not imported in this file. Add import sys at the top to avoid a NameError.

system = System([Top], output_directory=sys.argv[1])

[Copilot]

[nitpick] The function signature line for preprocess_op is very long and exceeds typical line-length recommendations. Consider breaking it into multiple lines or using a type alias for readability.

Suggested change

	preprocess_op: Optional[Callable[[ir.OpView],
	Optional[ir.OpView]]] = None,
	preprocess_op: PreprocessOpType = None,