re PR rtl-optimization/56833 (Valid register is over written by postreload pass)

re PR rtl-optimization/56833 (Valid register is over written by postreload pass)

        PR rtl-optimization/56833
        * postreload.c (move2add_record_mode): New function.
        (move2add_record_sym_value, move2add_valid_value_p): Likewise.
        (move2add_use_add2_insn): Use move2add_record_sym_value.
        (move2add_use_add3_insn): Likewise.
        (reload_cse_move2add): Use move2add_valid_value_p and
        move2add_record_mode.  Invalidate call-clobbered and REG_INC
        affected regs by setting reg_mode to VOIDmode.
        (move2add_note_store): Don't pretend the inside of a SUBREG is
        the actual destination.  Invalidate single/leading registers by
        setting reg_mode to VOIDmode.
        Use move2add_record_sym_value, move2add_valid_value_p and
        move2add_record_mode.

From-SVN: r199353