diff --git a/nemu/src/monitor/sdb/addrexp.y b/nemu/src/monitor/sdb/addrexp.y
index a77d83f..b783e3e 100644
--- a/nemu/src/monitor/sdb/addrexp.y
+++ b/nemu/src/monitor/sdb/addrexp.y
@@ -31,11 +31,6 @@ input
 
 expression
     : number { $$ = $1; }
-    | expression '>' '=' expression { $$ = ($1 >= $4); }
-    | expression '<' '=' expression { $$ = ($1 <= $4); }
-    | expression '=' '=' expression { $$ = ($1 == $4); }
-    | expression '!' '=' expression { $$ = ($1 == $4); }
-    | expression '>' expression { $$ = ($1 > $3); }
     | expression '<' expression { $$ = ($1 < $3); }
     | expression '+' expression { $$ = $1 + $3; }
     | expression '-' expression { $$ = $1 - $3; }