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#asm
;
;------------------------------------------------------------------
;       Small-C  Run-time Librray
;
;       V4d     As of July 16, 1980 (gtf)
;                  Added EXIT() function
;------------------------------------------------------------------
;
;Fetch a single byte from the address in HL and sign extend into HL
ccgchar: 
        ld a,(hl)
ccsxt:  
        ld l,a
        rlca
        sbc     a
        ld      h,a
        ret
;Fetch a full 16-bit integer from the address in HL
ccgint: 
        ld a,(hl)
        inc     hl
        ld      h,(hl)
        ld l,a
        ret
;Store a single byte from HL at the address in DE
ccpchar: 
        ld      a,l
        ld      (de),a
        ret
;Store a 16-bit integer in HL at the address in DE
ccpint: 
        ld      a,l
        ld      (de),a
        inc     de
        ld      a,h
        ld      (de),a
        ret
;Inclusive "or" HL and DE into HL
ccor:   
        ld      a,l
        or      e
        ld l,a
        ld      a,h
        or      d
        ld      h,a
        ret
;Exclusive "or" HL and DE into HL
ccxor:  
        ld      a,l
        xor     e
        ld l,a
        ld      a,h
        xor     d
        ld      h,a
        ret
;"And" HL and DE into HL
ccand:  
        ld      a,l
        and     e
        ld l,a
        ld      a,h
        and     d
        ld      h,a
        ret
;Test if HL = DE and set HL = 1 if true else 0
cceq:   
        call cccmp
        ret z
        dec     hl
        ret
;Test if DE ~= HL
ccne:   
        call cccmp
        ret nz
        dec     hl
        ret
;Test if DE > HL (signed)
ccgt:   
        ex de,hl
        call cccmp
        ret c
        dec     hl
        ret
;Test if DE <= HL (signed)
ccle:   
        call cccmp
        ret z
        ret c
        dec hl
        ret
;Test if DE >= HL (signed)
ccge:   
        call cccmp
        ret nc
        dec hl
        ret
;Test if DE < HL (signed)
cclt:   
        call cccmp
        ret c
        dec hl
        ret
; Signed compare of DE and HL
; Performs DE - HL and sets the conditions:
;       Carry reflects sign of difference (set means DE < HL)
;       Zero/non-zero set according to equality.
cccmp:
        ld      a,e
        sub     l
        ld      e,a
        ld      a,d
        sbc     h
        ld      hl,1
        jp      m,cccmp1
        or      e       ;"OR" resets carry
        ret
cccmp1: 
        or      e
        scf             ;set carry to signal minus
        ret
;Test if DE >= HL (unsigned)
ccuge:  
        call ccucmp
        ret nc
        dec hl
        ret     
;Test if DE < HL (unsigned)
ccult:  
        call ccucmp
        ret c
        dec hl
        ret
;Test if DE > HL (unsigned)
ccugt:  
        ex de,hl
        call ccucmp
        ret c
        dec hl
        ret
;Test if DE <= HL (unsigned)
ccule:  
        call ccucmp
        ret z
        ret c
        dec hl
        ret
;Routine to perform unsigned compare
;carry set if DE < HL
;zero/nonzero set accordingly
ccucmp: 
        ld      a,d
        cp      h
        jp      nz,$+5
        ld      a,e
        cp      l
        ld      hl,1
        ret
;Shift DE arithmetically right by HL and return in HL
ccasr:  
        ex      de,hl
        ld      a,h
        rla
        ld      a,h
        rra
        ld      h,a
        ld      a,l
        rra
        ld      l,a
        dec     e
        jp      nz,ccasr+1
        ret
;Shift DE arithmetically left by HL and return in HL
ccasl:  
        ex      de,hl
        add     hl,hl
        dec     e
        jp      nz,ccasl+1
        ret
;Subtract HL from DE and return in HL
ccsub:  
        ld      a,e
        sub     l
        ld l,a
        ld      a,d
        sbc     h
        ld      h,a
        ret
;Form the two's complement of HL
ccneg:  
        call cccom
        inc     hl
        ret
;Form the one's complement of HL
cccom:  
        ld      a,h
        cpl
        ld      h,a
        ld      a,l
        cpl
        ld l,a
        ret
;Multiply DE by HL and return in HL
ccmult: 
        ld      b,h
        ld      c,l
        ld      hl,0
ccmult1: 
        ld      a,c
        rrca
        jp      nc,$+4
        add     hl,de
        xor     a
        ld      a,b
        rra
        ld      b,a
        ld      a,c
        rra
        ld      c,a
        or      b
        ret z
        xor     a
        ld      a,e
        rla
        ld      e,a
        ld      a,d
        rla
        ld      d,a
        or      e
        ret z
        jp      ccmult1
;Divide DE by HL and return quotient in HL, remainder in DE
ccdiv:  
        ld      b,h
        ld      c,l
        ld      a,d
        xor     b
        push af
        ld      a,d
        or      a
        call m,ccdeneg
        ld      a,b
        or      a
        call m,ccbcneg
        ld      a,16
        push af 
        ex      de,hl
        ld      de,0
ccdiv1: 
        add hl,hl 
        call ccrdel
        jp      z,ccdiv2
        call cccmpbcde
        jp      m,ccdiv2
        ld      a,l
        or      1
        ld l,a
        ld      a,e
        sub     c
        ld      e,a
        ld      a,d
        sbc     b
        ld      d,a
ccdiv2: 
        pop af
        dec     a
        jp      z,ccdiv3
        push af
        jp      ccdiv1
ccdiv3: 
        pop af
        ret     p
        call ccdeneg
        ex de,hl
        call ccdeneg
        ex de,hl
        ret
ccdeneg: 
        ld      a,d
        cpl
        ld      d,a
        ld      a,e
        cpl
        ld      e,a
        inc     de
        ret
ccbcneg: 
        ld      a,b
        cpl
        ld      b,a
        ld      a,c
        cpl
        ld      c,a
        inc     bc
        ret
ccrdel: 
        ld      a,e
        rla
        ld      e,a
        ld      a,d
        rla
        ld      d,a
        or      e
        ret
cccmpbcde: 
        ld      a,e
        sub     c
        ld      a,d
        sbc     b
        ret

#endasm