* rtl.h (RTX_FLAG): New macro.
* emit-rtl.c (copy_most_rtx): Use macros to access rtx flags.
* final.c (alter_subreg): Use macro to access rtx flag.
* integrate.c (copy_rtx_and_substitute): Use new access macro.
* print-rtl.c (print_rtx): Use new access macro.
* cse.c (insert): Check rtx code before accessing flag.