[#74021] add source comment at the beginning of the SAIF file

include/verilated_saif_c.cpp

@@ -186,6 +186,7 @@ void VerilatedSaif::openNextImp(bool incFilename) {
 }
 
 void VerilatedSaif::initializeSaifFileContents() {
+    printStr("// Generated by verilated_saif\n");
     printStr("(SAIFILE\n");
     printStr("(SAIFVERSION \"2.0\")\n");
     printStr("(DIRECTION \"backward\")\n");

nodist/verilator_saif_diff

@@ -73,7 +73,9 @@ class SAIFParser:
         file_contents = ''
 
         with open(saif_filename, 'r', encoding="utf8") as saif_file:
-            file_contents = saif_file.read()
+            content = saif_file.readlines()
+            filtered_lines = [line for line in content if not line.strip().startswith('//')]
+            file_contents = ''.join(filtered_lines)
 
         tokens = file_contents.replace('(', ' ( ').replace(')', ' ) ').split()
         num_of_tokens = len(tokens)