diff --git a/tools/disassembler/disassembler.c b/tools/disassembler/disassembler.c
index 678589e..17e6350 100644
--- a/tools/disassembler/disassembler.c
+++ b/tools/disassembler/disassembler.c
@@ -906,7 +906,8 @@ void disassemble(const char *filename, options_t config) {
 
             if (!strcmp(litf->fun, "MAIN")) {
                 printf("MAIN:\n");
-                printf("%s", litf->str);
+                printf("%s", str_replace_substr_all(litf->str, ".lit FUNCTION ", ".lit FUNCTION (code=FUN_) "));
+
                 dis_disassemble_section(&prg, prg->pc, prg->len, 0, false, config);
                 free(litf->fun);
                 free(litf->str);
@@ -915,8 +916,10 @@ void disassemble(const char *filename, options_t config) {
                 continue;
             }
 
-            printf("FUNCTION_%s:\n", litf->fun);
-            printf("%s", litf->str);
+            printf("FUN_%s:\n", litf->fun);
+            char sbtr[strlen(litf->fun) +  19];
+            sprintf(sbtr, ".lit FUNCTION (code=FUN_%s_) ", litf->fun);
+            printf("%s", str_replace_substr_all(litf->str, ".lit FUNCTION ", sbtr));
 
             queue_node_t *fqf = function_queue_front;
             while (fqf != NULL) {
diff --git a/tools/disassembler/disassembler_utils.c b/tools/disassembler/disassembler_utils.c
index 4ccc72c..fdfd8fe 100644
--- a/tools/disassembler/disassembler_utils.c
+++ b/tools/disassembler/disassembler_utils.c
@@ -58,3 +58,35 @@ void str_append(char **str, const char *app) {
     *str = realloc(*str, (strlen(*str) + strlen(app) + 1) * sizeof(char));
     memcpy((*str) + strlen(*str), app, strlen(app) + 1);
 }
+
+char* str_replace_substr_all(char *mainstr, char *substr, char *newstr) {
+    int lenmain, lensub, i, j, lennew, startindex = -1, c;
+    lenmain = strlen(mainstr);
+    lensub = strlen(substr);
+    lennew = strlen(newstr);
+    char *result = (char*) malloc(sizeof(char) * (lenmain + 200));
+    for (c = 0, i = 0; i < lenmain; i++) {
+        if (lenmain - i >= lensub && *(mainstr + i) == *(substr)) {
+            startindex = i;
+            for (j = 1; j < lensub; j++)
+                if (*(mainstr + i + j) != *(substr + j)) {
+                    startindex = -1;
+                    break;
+                }
+            if (startindex != -1) {
+                for (j = 0; j < lennew; j++, c++) {
+                    *(result + c) = *(newstr + j);
+                }
+                i = i + lensub - 1;
+            } else {
+                *(result + c) = *(mainstr + i);
+                c++;
+            }
+        } else {
+            *(result + c) = *(mainstr + i);
+            c++;
+        }
+    }
+    *(result + c) = '\0';
+    return result;
+}
diff --git a/tools/disassembler/disassembler_utils.h b/tools/disassembler/disassembler_utils.h
index ef0a95a..205c7e0 100644
--- a/tools/disassembler/disassembler_utils.h
+++ b/tools/disassembler/disassembler_utils.h
@@ -21,5 +21,6 @@ void dis_enqueue(void *x, queue_node_t **queue_front, queue_node_t **queue_rear,
 void dis_dequeue(queue_node_t **queue_front, queue_node_t **queue_rear, uint32_t *len);
 
 void str_append(char **str, const char *app);
+char* str_replace_substr_all(char *mainstr, char *substr, char *newstr);
 
 #endif /* UTILS_H_ */