Backport #557 (#570)

Backport https://github.com/QuEraComputing/kirin/pull/557/files

Author: rafaelha

src/kirin/dialects/ilist/rewrite/inline_getitem.py

@@ -25,6 +25,9 @@ def rewrite_Statement(self, node: ir.Statement) -> abc.RewriteResult:
         if not isinstance(index_const := node.index.hints.get("const"), const.Value):
             return abc.RewriteResult()
 
+        if not node.result.uses:
+            return abc.RewriteResult()
+
         index = index_const.data
         if isinstance(index, int) and (
             0 <= index < len(stmt.args) or -len(stmt.args) <= index < 0

src/kirin/rewrite/getitem.py

@@ -19,6 +19,9 @@ def rewrite_Statement(self, node: ir.Statement) -> RewriteResult:
         if not isinstance(index_value := node.index.hints.get("const"), const.Value):
             return RewriteResult()
 
+        if not node.result.uses:
+            return RewriteResult()
+
         stmt = node.obj.owner
         index = index_value.data
         if isinstance(index, int) and (

test/dialects/test_ilist.py

@@ -207,7 +207,8 @@ def test_inline_getitem_slice():
         [
             qreg := ilist.New(values=values),
             slice_value := py.Constant(slice(2, 5, 1)),
-            py.GetItem(obj=qreg.result, index=slice_value.result),
+            res := py.GetItem(obj=qreg.result, index=slice_value.result),
+            func.Return(res.result),
         ]
     )
     slice_value.result.hints["const"] = const.Value(slice(2, 5, 1))
@@ -219,7 +220,8 @@ def test_inline_getitem_slice():
         [
             qreg := ilist.New(values=values),
             slice_value := py.Constant(slice(2, 5, 1)),
-            ilist.New(values=(values[2], values[3], values[4])),
+            res := ilist.New(values=(values[2], values[3], values[4])),
+            func.Return(res.result),
         ]
     )
     assert test_block.is_equal(expected_block)