diff --git a/suite/regress/x64_bigint.py b/suite/regress/x64_bigint.py
index a370f3b4bc0f764904fdde5d80f2fbdd7535e86f..187e47824561098320d29feeef8ed8359e41962b 100755
--- a/suite/regress/x64_bigint.py
+++ b/suite/regress/x64_bigint.py
@@ -1,6 +1,8 @@
 #!/usr/bin/python
 # Nguyen Anh Quynh, 2016
 
+# This tests alias instructions of MOV RDI, <big-int-numbers>
+
 # Fill in the information in the form below when you create a new regression
 
 # Github issue: #12
@@ -15,10 +17,17 @@ class TestX86(regress.RegressTest):
         # Initialize Keystone engine
         ks = Ks(KS_ARCH_X86, KS_MODE_64)
         # Assemble to get back insn encoding & statement count
-        # encoding, count = ks.asm("mov rdi, 0x1122334455")
+        encoding, count = ks.asm("mov rdi, 0x1122334455")
+        # Assert the result
+        self.assertEqual(encoding, [ 0x48, 0xBF, 0x55, 0x44, 0x33, 0x22, 0x11, 0x00, 0x00, 0x00 ])
+
         encoding, count = ks.asm("movabs rdi, 0x1122334455")
         # Assert the result
         self.assertEqual(encoding, [ 0x48, 0xBF, 0x55, 0x44, 0x33, 0x22, 0x11, 0x00, 0x00, 0x00 ])
 
+        encoding, count = ks.asm("movq rdi, 0x1122334455")
+        # Assert the result
+        self.assertEqual(encoding, [ 0x48, 0xBF, 0x55, 0x44, 0x33, 0x22, 0x11, 0x00, 0x00, 0x00 ])
+
 if __name__ == '__main__':
     regress.main()