Stack Frame Words

                code    "{", frame              ; Open a stack access context
                incd    rrRP
                putd    rrRP, rrFRAME
                mov     rrFRAME, rrSP
                decd    rrFRAME
                next

                code    "}", unframe            ; close a stack access context
                incd    rrFRAME
                mov     rrSP, rrFRAME
                getd    rrFRAME, rrRP
                decd    rrRP
                shl     rrTOS, 3
                radd    rrSP, rrTOS
                getd    rrTOS, rrSP-8           ; recovers TOS from { state
                next
                code    "s0", s0                ; push rrFRAME onto stack
                decd    rrSP
                putd    rrSP, rrTOS
                mov     rrTOS, rrFRAME
                next

                code    "s1", s1                ; push rrFRAME plus one cell
                decd    rrSP
                putd    rrSP, rrTOS
                mov     rrTOS, rrFRAME
                incd    rrTOS
                next

                code    "s2", s2                ; push rrFRAME plus two cells
                decd    rrSP
                putd    rrSP, rrTOS
                mov     rrTOS, rrFRAME
                add     rrTOS, 16
                next

                code    "s3", s3                ; push rrFRAME plus three cells
                decd    rrSP
                putd    rrSP, rrTOS
                mov     rrTOS, rrFRAME
                add     rrTOS, 24
                next

                code    "s4", s4                ; push rrFRAME plus four cells
                decd    rrSP
                putd    rrSP, rrTOS
                mov     rrTOS, rrFRAME
                add     rrTOS, 32
                next