Fix circular import error. issue #549 (#550)

Fixes bug in issue #549: circular import error when importing
`kirin.dialects.py`.

Small edits to `src/kirin/dialects/func/closurefield.py` and
`src/kirin/dialects/func/lambdalifting.py`.
Delaying import.

Author: zhenrongliew

src/kirin/dialects/func/__init__.py

@@ -20,6 +20,4 @@
 
 from . import (
     _julia as _julia,
-    closurefield as closurefield,
-    lambdalifting as lambdalifting,
 )

src/kirin/dialects/func/rewrite/__init__.py

@@ -0,0 +1,2 @@
+from .closurefield import ClosureField as ClosureField
+from .lambdalifting import LambdaLifting as LambdaLifting

src/kirin/dialects/func/closurefield.py renamed to src/kirin/dialects/func/rewrite/closurefield.py

@@ -1,8 +1,9 @@
 from kirin import ir
-from kirin.dialects import py, func
+from kirin.passes import TypeInfer
 from kirin.rewrite.abc import RewriteRule, RewriteResult
 
-from ._dialect import dialect
+from ..stmts import Invoke, GetField
+from .._dialect import dialect
 
 
 @dialect.canonicalize
@@ -13,7 +14,7 @@ class ClosureField(RewriteRule):
     """
 
     def rewrite_Statement(self, node: ir.Statement) -> RewriteResult:
-        if not isinstance(node, func.Invoke):
+        if not isinstance(node, Invoke):
             return RewriteResult(has_done_something=False)
         method = node.callee
         if not method.fields:
@@ -22,12 +23,11 @@ def rewrite_Statement(self, node: ir.Statement) -> RewriteResult:
         changed = self._lower_captured_fields(method)
         if changed:
             method.fields = ()
-        from kirin.passes import TypeInfer
 
         rewrite_result = TypeInfer(dialects=method.dialects).unsafe_run(method)
         return RewriteResult(has_done_something=changed).join(rewrite_result)
 
-    def _get_field_index(self, getfield_stmt: func.GetField) -> int | None:
+    def _get_field_index(self, getfield_stmt: GetField) -> int | None:
         fld = getfield_stmt.attributes.get("field")
         if fld:
             return getfield_stmt.field
@@ -43,7 +43,7 @@ def _lower_captured_fields(self, method: ir.Method) -> bool:
         for region in method.code.regions:
             for block in region.blocks:
                 for stmt in list(block.stmts):
-                    if not isinstance(stmt, func.GetField):
+                    if not isinstance(stmt, GetField):
                         continue
                     idx = self._get_field_index(stmt)
                     if idx is None:
@@ -53,6 +53,8 @@ def _lower_captured_fields(self, method: ir.Method) -> bool:
                     if isinstance(captured, ir.Method):
                         continue
                     # Replace GetField with Constant.
+                    from kirin.dialects import py
+
                     const_stmt = py.Constant(captured)
                     const_stmt.insert_before(stmt)
                     if stmt.results and const_stmt.results:

src/kirin/dialects/func/lambdalifting.py renamed to src/kirin/dialects/func/rewrite/lambdalifting.py

@@ -1,8 +1,10 @@
 from kirin import ir
-from kirin.dialects import py, func
+from kirin.passes import TypeInfer
+from kirin.dialects import py
 from kirin.rewrite.abc import RewriteRule, RewriteResult
 
-from ._dialect import dialect
+from ..stmts import Lambda, Function, GetField
+from .._dialect import dialect
 
 
 @dialect.canonicalize
@@ -12,17 +14,17 @@ class LambdaLifting(RewriteRule):
     """
 
     def rewrite_Statement(self, node: ir.Statement) -> RewriteResult:
+        from kirin.dialects import py
+
         if not isinstance(node, py.Constant):
             return RewriteResult(has_done_something=False)
         method = self._get_method_from_constant(node)
         if method is None:
             return RewriteResult(has_done_something=False)
-        if not isinstance(method.code, func.Lambda):
+        if not isinstance(method.code, Lambda):
             return RewriteResult(has_done_something=False)
         self._promote_lambda(method)
 
-        from kirin.passes import TypeInfer
-
         rewrite_result = TypeInfer(dialects=method.dialects).unsafe_run(method)
         return RewriteResult(has_done_something=True).join(rewrite_result)
 
@@ -34,7 +36,7 @@ def _get_method_from_constant(self, const_stmt: py.Constant) -> ir.Method | None
             return pyattr_data.data
         return None
 
-    def _get_field_index(self, getfield_stmt: func.GetField) -> int | None:
+    def _get_field_index(self, getfield_stmt: GetField) -> int | None:
         fld = getfield_stmt.attributes.get("field")
         if fld:
             return getfield_stmt.field
@@ -44,26 +46,28 @@ def _get_field_index(self, getfield_stmt: func.GetField) -> int | None:
     def _promote_lambda(self, method: ir.Method) -> None:
         new_method = method.similar()
         assert isinstance(
-            new_method.code, func.Lambda
+            new_method.code, Lambda
         ), "expected method.code to be func.Lambda before promotion"
 
         captured_fields = method.fields
         if captured_fields:
             for stmt in new_method.code.body.blocks[0].stmts:
-                if not isinstance(stmt, func.GetField):
+                if not isinstance(stmt, GetField):
                     continue
                 idx = self._get_field_index(stmt)
                 if idx is None:
                     continue
                 captured = new_method.fields[idx]
+                from kirin.dialects import py
+
                 const_stmt = py.Constant(captured)
                 const_stmt.insert_before(stmt)
                 if stmt.results and const_stmt.results:
                     stmt.results[0].replace_by(const_stmt.results[0])
                 stmt.delete()
                 new_method.code
 
-        fn = func.Function(
+        fn = Function(
             sym_name=new_method.code.sym_name,
             slots=new_method.code.slots,
             signature=new_method.code.signature,

test/dialects/func/test_closurefield.py

@@ -3,6 +3,7 @@
 from kirin import rewrite
 from kirin.prelude import basic
 from kirin.dialects import py, func
+from kirin.dialects.func.rewrite import closurefield
 
 
 def test_rewrite_closure_inner_lambda():
@@ -26,7 +27,7 @@ def main_lambda(z: int):
         inner_getfield_stmt, func.GetField
     ), "expected GetField before rewrite"
 
-    rewrite.Walk(func.closurefield.ClosureField()).rewrite(main_lambda.code)
+    rewrite.Walk(closurefield.ClosureField()).rewrite(main_lambda.code)
 
     inner_getfield_stmt = inner_lambda.regions[0].blocks[0].stmts.at(0)
     assert isinstance(
@@ -47,6 +48,6 @@ def boo(y):
         return boo(4)
 
     before = bar.code.regions[0].blocks[0].stmts.at(0)
-    rewrite.Walk(func.closurefield.ClosureField()).rewrite(bar.code)
+    rewrite.Walk(closurefield.ClosureField()).rewrite(bar.code)
     after = bar.code.regions[0].blocks[0].stmts.at(0)
     assert before is after

test/dialects/func/test_lambdalifting.py

@@ -1,6 +1,7 @@
 from kirin import ir, rewrite
 from kirin.prelude import basic
 from kirin.dialects import py, func
+from kirin.dialects.func.rewrite import lambdalifting
 
 
 def test_rewrite_inner_lambda():
@@ -20,7 +21,7 @@ def inner(x: int):
         pyconstant_stmt.value.data.code, func.Lambda
     ), "expected a lambda Method in outer body"
 
-    rewrite.Walk(func.lambdalifting.LambdaLifting()).rewrite(outer.code)
+    rewrite.Walk(lambdalifting.LambdaLifting()).rewrite(outer.code)
     assert isinstance(
         pyconstant_stmt.value.data.code, func.Function
     ), "expected a Function in outer body"
@@ -45,7 +46,7 @@ def inner2(x: int):
     assert isinstance(
         pyconstant_stmt.value.data.code, func.Lambda
     ), "expected a lambda Method in outer body"
-    rewrite.Walk(func.lambdalifting.LambdaLifting()).rewrite(outer2.code)
+    rewrite.Walk(lambdalifting.LambdaLifting()).rewrite(outer2.code)
     assert isinstance(
         pyconstant_stmt.value.data.code, func.Function
     ), "expected a Function in outer body"