Forth Exception Frames

                code    "{|", eframe            ; open exception frame
                add     rrRP, 24
                putd    rrRP-16, rrEXP
                putd    rrRP-8, rrFRAME
                putd    rrRP, rrSP
                mov     rrFRAME, rrSP
                decd    rrFRAME
                mov     rrEXP, rrRP
                next

                code    "|}", eunframe          ; close exception frame
                mov     rrRP, rrEXP
                incd    rrFRAME
                mov     rrSP, rrFRAME
                getd    rrSP, rrRP
                getd    rrFRAME, rrRP-8
                getd    rrEXP,  rrRP-16
                sub     rrRP, 24
                next