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;
; Ullrich von Bassewitz, 17.08.1998
;
; CC65 runtime: division for signed long ints
;
; When negating values, we will ignore the possibility here, that one of the
; values if $80000000, in which case the negate will fail.
.export tosdiv0ax, tosdiveax
.import poplsargs, udiv32, negeax
.importzp sreg, ptr1, tmp1, tmp2
tosdiv0ax:
ldy #$00
sty sreg
sty sreg+1
tosdiveax:
jsr poplsargs ; Get arguments from stack, adjust sign
jsr udiv32 ; Do the division, result is in (ptr1:sreg)
ldx ptr1+1 ; Load byte 1 of result
; Adjust the sign of the result
lda tmp1 ; Get sign of left operand
eor tmp2 ; Calculate sign of result
bpl Pos ; Jump if result positive
; Result is negative
lda ptr1 ; Load byte 0
jmp negeax ; Negate value
; Result is positive
Pos: lda ptr1
rts
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