diff --git a/osaca/parser/parser_AArch64.py b/osaca/parser/parser_AArch64.py
index c21bd30..714192d 100644
--- a/osaca/parser/parser_AArch64.py
+++ b/osaca/parser/parser_AArch64.py
@@ -390,12 +390,10 @@ class ParserAArch64(BaseParser):
 
     def process_directive_operand(self, operand):
         return DirectiveOperand(
-                name=operand["name"],
-                parameter_id=operand["parameters"],
-                comment_id=operand["comment"]
-                if "comment" in operand
-                else None,
-            )
+            name=operand["name"],
+            parameter_id=operand["parameters"],
+            comment_id=operand["comment"] if "comment" in operand else None,
+        )
 
     def process_register_operand(self, operand):
         return RegisterOperand(
@@ -435,7 +433,9 @@ class ParserAArch64(BaseParser):
                     scale = 2 ** int(memory_address["index"]["shift"][0]["value"])
         if index is not None:
             index = RegisterOperand(
-                name=index["name"], prefix_id=index["prefix"] if "prefix" in index else None
+                name=index["name"], prefix_id=index["prefix"] if "prefix" in index else None,
+                shift=index["shift"] if "shift" in index else None,
+                shift_op=index["shift_op"] if "shift_op" in index else None
             )
         new_dict = MemoryOperand(
             offset_ID=offset,
diff --git a/osaca/parser/parser_x86att.py b/osaca/parser/parser_x86att.py
index ee390a5..7ca2dec 100644
--- a/osaca/parser/parser_x86att.py
+++ b/osaca/parser/parser_x86att.py
@@ -305,17 +305,13 @@ class ParserX86ATT(BaseParser):
 
     def process_register(self, operand):
         return RegisterOperand(
-                prefix_id=operand["prefix"]
-                if "prefix" in operand
-                else None,
-                name=operand["name"],
-                shape=operand["shape"] if "shape" in operand else None,
-                lanes=operand["lanes"] if "lanes" in operand else None,
-                index=operand["index"] if "index" in operand else None,
-                predication=operand["predication"]
-                if "predication" in operand
-                else None,
-            )
+            prefix_id=operand["prefix"] if "prefix" in operand else None,
+            name=operand["name"],
+            shape=operand["shape"] if "shape" in operand else None,
+            lanes=operand["lanes"] if "lanes" in operand else None,
+            index=operand["index"] if "index" in operand else None,
+            predication=operand["predication"] if "predication" in operand else None,
+        )
 
     def process_directive(self, directive):
         directive_new = DirectiveOperand(name=directive["name"], parameter_id=[])
@@ -367,7 +363,6 @@ class ParserX86ATT(BaseParser):
             name=label["name"], comment_id=label["comment"] if "comment" in label else None
         )
 
-
     def process_immediate(self, immediate):
         """Post-process immediate operand"""
         if "identifier" in immediate:
diff --git a/osaca/parser/register.py b/osaca/parser/register.py
index 4391d5c..ad84b5c 100644
--- a/osaca/parser/register.py
+++ b/osaca/parser/register.py
@@ -21,6 +21,8 @@ class RegisterOperand(Operand):
         destination=False,
         pre_indexed=False,
         post_indexed=False,
+        shift=False,
+        shift_op=False
     ):
         super().__init__(name, source, destination)
         self._width_id = width_id
@@ -35,6 +37,8 @@ class RegisterOperand(Operand):
         self._predication = predication
         self._pre_indexed = pre_indexed
         self._post_indexed = post_indexed
+        self._shift = shift
+        self._shift_op = shift_op
 
     @property
     def width(self):
@@ -44,6 +48,22 @@ class RegisterOperand(Operand):
     def width(self, width):
         self._width_id = width
 
+    @property
+    def shift(self):
+        return self._shift
+
+    @shift.setter
+    def shift(self, shift):
+        self._shift = shift
+
+    @property
+    def shift_op(self):
+        return self._shift_op
+
+    @shift_op.setter
+    def shift_op(self, shift_op):
+        self._shift_op = shift_op
+
     @property
     def predication(self):
         return self._predication
diff --git a/tests/test_parser_AArch64.py b/tests/test_parser_AArch64.py
index ce810aa..7fe8afb 100755
--- a/tests/test_parser_AArch64.py
+++ b/tests/test_parser_AArch64.py
@@ -216,13 +216,7 @@ class TestParserAArch64(unittest.TestCase):
                 MemoryOperand(
                     offset_ID=None,
                     base_id=RegisterOperand(prefix_id="x", name="11"),
-                    index_id={
-                        "prefix": "w",
-                        "name": "10",
-                        "shift_op": "sxtw",
-                        "immediate": {"value": "2"},
-                        "shift": [{"value": "2"}],
-                    },
+                    index_id=RegisterOperand(prefix_id="w", name="10", shift_op="sxtw", shift=[{"value": "2"}]),
                     scale_id=4,
                 ),
             ],