diff --git a/boot.c b/boot.c
index 85cc5d0..3d41e6e 100644
--- a/boot.c
+++ b/boot.c
@@ -884,22 +884,40 @@ int parse_add_expr() {
     return lhs;
 }
 
-int parse_cmp_expr() {
+int parse_shift_expr() {
     int lhs = parse_add_expr();
     while (1) {
         next_token();
-        if (token_type == TOKEN_LT) {
+        if (token_type == TOKEN_LSHIFT) {
             int rhs = parse_add_expr();
+            lhs = asm_rr("sll", lhs, rhs);
+        } else if (token_type == TOKEN_RSHIFT) {
+            int rhs = parse_add_expr();
+            lhs = asm_rr("sra", lhs, rhs);
+        } else {
+            unget_token();
+            break;
+        }
+    }
+    return lhs;
+}
+
+int parse_cmp_expr() {
+    int lhs = parse_shift_expr();
+    while (1) {
+        next_token();
+        if (token_type == TOKEN_LT) {
+            int rhs = parse_shift_expr();
             lhs = asm_rr("slt", lhs, rhs);
         } else if (token_type == TOKEN_GT) {
-            int rhs = parse_add_expr();
+            int rhs = parse_shift_expr();
             lhs = asm_rr("sgt", lhs, rhs);
         } else if (token_type == TOKEN_LE) {
-            int rhs = parse_add_expr();
+            int rhs = parse_shift_expr();
             int sgt = asm_rr("sgt", lhs, rhs);
             lhs = asm_r("seqz", sgt);
         } else if (token_type == TOKEN_GE) {
-            int rhs = parse_add_expr();
+            int rhs = parse_shift_expr();
             int slt = asm_rr("slt", lhs, rhs);
             lhs = asm_r("seqz", slt);
         } else {