+int RegAXUsed (struct CodeSeg* S, unsigned Index);
+/* Check if the value in A or(!) the value in X are used. */
+
+int RegEAXUsed (struct CodeSeg* S, unsigned Index);
+/* Check if any of the four bytes in EAX are used. */
+
+unsigned GetKnownReg (unsigned Use, const struct RegContents* RC);
+/* Return the register or zero page location from the set in Use, thats
+ * contents are known. If Use does not contain any register, or if the
+ * register in question does not have a known value, return REG_NONE.
+ */
+
+cmp_t FindBoolCmpCond (const char* Name);
+/* Check if the given string is the name of one of the boolean transformer
+ * subroutine, and if so, return the condition that is evaluated by this
+ * routine. Return CMP_INV if the condition is not recognised.
+ */
+
+cmp_t FindTosCmpCond (const char* Name);
+/* Check if this is a call to one of the TOS compare functions (tosgtax).
+ * Return the condition code or CMP_INV on failure.
+ */
+