[mlir][python] Include anchor op in PassManager constructor

This adds an extra argument for specifying the pass manager's anchor op,
with a default of `any`. Previously the anchor was always defaulted to
`builtin.module`.

Reviewed By: mehdi_amini

Differential Revision: https://reviews.llvm.org/D136406

Author: rkayaith

mlir/lib/Bindings/Python/Pass.cpp

@@ -56,11 +56,14 @@ void mlir::python::populatePassManagerSubmodule(py::module &m) {
   // Mapping of the top-level PassManager
   //----------------------------------------------------------------------------
   py::class_<PyPassManager>(m, "PassManager", py::module_local())
-      .def(py::init<>([](DefaultingPyMlirContext context) {
-             MlirPassManager passManager =
-                 mlirPassManagerCreate(context->get());
+      .def(py::init<>([](const std::string &anchorOp,
+                         DefaultingPyMlirContext context) {
+             MlirPassManager passManager = mlirPassManagerCreateOnOperation(
+                 context->get(),
+                 mlirStringRefCreate(anchorOp.data(), anchorOp.size()));
              return new PyPassManager(passManager);
            }),
+           py::arg("anchor_op") = py::str("any"),
            py::arg("context") = py::none(),
            "Create a new PassManager for the current (or provided) Context.")
       .def_property_readonly(MLIR_PYTHON_CAPI_PTR_ATTR,

mlir/test/python/pass_manager.py

@@ -28,6 +28,17 @@ def testCapsule():
     assert pm1 is not None  # And does not crash.
 run(testCapsule)
 
+# CHECK-LABEL: TEST: testConstruct
+@run
+def testConstruct():
+  with Context():
+    # CHECK: pm1: 'any()'
+    # CHECK: pm2: 'builtin.module()'
+    pm1 = PassManager()
+    pm2 = PassManager("builtin.module")
+    log(f"pm1: '{pm1}'")
+    log(f"pm2: '{pm2}'")
+
 
 # Verify successful round-trip.
 # CHECK-LABEL: TEST: testParseSuccess