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[r3931]

ir/opt/ldstopt.h

@@ -25,7 +25,25 @@
  *
  * Removes redundand non-volatile Loads and Stores.
  * May introduce Bad nodes if exceptional control flow
- * is removed.
+ * is removed. The following cases are optimized:
+ *
+ * Load without result: A Load which has only a memory use
+ *   is removed.
+ *
+ * Load after Store: A Load after a Store is removed, if
+ *   the Load doesn't have an exception handler or is in
+ *   the same block as the Store.
+ *
+ * Load after Load: A Load after a Load is removed, if the
+ *   Load doesn't have an exception handler or is in the
+ *   same block as the previous Load.
+ *
+ * Store before Store: A Store immediately before another
+ *   Store in the same block is removed, if the Store doesn't
+ *   have an exception handler.
+ *
+ * Store after Load: A Store after a Load is removed, if the
+ *   Store doesn't have an exception handler.
  */
 void optimize_load_store(ir_graph *irg);