;       Small C+ Math Library
;       sqrt(a) function, compiled C..hence the size!
;       Compiled using some inline optimizations (gchar etc)

;       Fine tuned by hand...so don't recompile!
;       Tuned to: only keep one zero constant
;       Pointer stuff made nicer..
;
;       But still not working!


        XLIB    sqrt

        XREF    dload
        XREF    dpush
        XREF    deq
        XREF    dlt
        XREF    dstore
        XREF    dldpsh
        LIB     l_pint
        LIB     l_gint
        XREF    ddiv
        XREF    dadd


.sqrt
        ld      hl,-12
        add     hl,sp
        ld      sp,hl
        ld      hl,14
        add     hl,sp
; call dload, dpush -> dldpsh
        call    dldpsh
        ld      hl,i_1+0
        call    dload
        call    deq
        ld      a,h
        or      l
        jp      z,i_2
        ld      hl,i_1+0
        call    dload
        ld      hl,12
        add     hl,sp
        ld      sp,hl
        ret


.i_2
        ld      hl,14
        add     hl,sp
; call dload, dpush -> dldpsh
        call    dldpsh
        ld      hl,i_1+0
        call    dload
        call    dlt
        ld      a,h
        or      l
        jp      z,i_3
        ld      hl,i_1+0
        call    dload
        ex      de,hl
        ld      hl,12
        add     hl,sp
        ld      sp,hl
        ex      de,hl
        ret


.i_3
        ld      hl,4
        add     hl,sp
        push    hl
        ld      hl,16
        add     hl,sp
        pop     de
        call    l_pint
        ld      hl,6
        add     hl,sp
        pop     de
        pop     bc
        push    hl
        push    de
        ld      hl,6
        add     hl,sp
        push    hl
        ld      hl,i_1+6
        call    dload
        pop     hl
        call    dstore
;Fetch second into off stack optimized
        pop     bc
        pop     hl
        push    hl
        push    bc

        ld      de,5
        add     hl,de
        push    hl
        ld      hl,6
        add     hl,sp
        call    l_gint
        ld      de,5
        add     hl,de
        ld      a,(hl)
;right shift xor 64     ;exponent
        srl     a
        xor     64
        pop     hl
        ld      (hl),a
        ld      hl,5
        pop     bc
        push    hl
.i_4
;Decrement int at top of stack (from j--)
        pop     hl
        dec     hl
        push    hl
        ld      a,h
        or      l
        jp      z,i_5
        ld      hl,6
        add     hl,sp
        push    hl
; call dload, dpush -> dldpsh
        call    dldpsh
        ld      hl,22
        add     hl,sp
; call dload, dpush -> dldpsh
        call    dldpsh
        ld      hl,20
        add     hl,sp
        call    dload
        call    ddiv
        call    dadd
        pop     hl
        call    dstore
;Fetch second into off stack optimized
        pop     bc
        pop     hl
        push    hl
        push    bc
        ld      de,5
        add     hl,de
        dec     (hl)
        jp      i_4
.i_5
        ld      hl,6
        add     hl,sp
        call    dload
        ld      hl,12
        add     hl,sp
        ld      sp,hl
        ret


.i_1
        defb    0,0,0,0,0,0
        defb    18,-125,-64,-54,65,-128