extern int constrain_operands_cached (int);
extern int memory_address_p (enum machine_mode, rtx);
extern int strict_memory_address_p (enum machine_mode, rtx);
+extern int validate_replace_rtx_subexp (rtx, rtx, rtx, rtx *);
extern int validate_replace_rtx (rtx, rtx, rtx);
extern int validate_replace_rtx_part (rtx, rtx, rtx *, rtx);
extern int validate_replace_rtx_part_nosimplify (rtx, rtx, rtx *, rtx);