+extern void hist_read_rec (FILE *, const char *);
+extern void hist_write_hist (FILE *, const char *);
+extern void hist_assign_samples (void);
+extern void hist_print (void);
+
+/* Checks if ADDRESS is within the range of addresses for which
+ we have histogram data. Returns 1 if so and 0 otherwise. */
+extern int hist_check_address (unsigned address);
+
+/* Given a range of addresses for a symbol, find a histogram record
+ that intersects with this range, and clips the range to that
+ histogram record, modifying *P_LOWPC and *P_HIGHPC.