fixed the bug not popping an argument in the _integer_inttostr primitive.

added a new primitive _processor_return_to_and_eval to support proper exception handling

stix/lib/stix.h

@@ -900,7 +900,7 @@ enum stix_log_mask_t
 
 	STIX_LOG_MNEMONIC = (1 << 8), /* bytecode mnemonic */
 	STIX_LOG_GC       = (1 << 9),
-	STIX_LOG_VM       = (1 << 10)
+	STIX_LOG_IC       = (1 << 10) /* instruction cycle, fetch-decode-execute */
 };
 typedef enum stix_log_mask_t stix_log_mask_t;