+unsigned OptStore4 (CodeSeg* S);
+/* Search for the sequence
+ *
+ * sta xx
+ * stx yy
+ * lda xx
+ * ldx yy
+ *
+ * and remove the useless load, provided that the next insn doesn't use flags
+ * from the load.
+ */
+
+unsigned OptStore5 (CodeSeg* S);
+/* Search for the sequence
+ *
+ * lda foo
+ * ldx bar
+ * sta something
+ * stx something-else
+ *
+ * and replace it by
+ *
+ * lda foo
+ * sta something
+ * lda bar
+ * sta something-else
+ *
+ * if X is not used later. This replacement doesn't save any cycles or bytes,
+ * but it keeps the value of X, which may be reused later.
+ */
+