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;
; Ullrich von Bassewitz, 07.08.1998
;
; CC65 runtime: division for signed ints
;
; When negating values, we will ignore the possibility here, that one of the
; values is $8000, in which case the negate will fail.
.export tosdiva0, tosdivax
.import popsargsudiv16, negax
.importzp ptr1, tmp1, tmp2
tosdiva0:
ldx #0
tosdivax:
jsr popsargsudiv16 ; Get arguments from stack, adjust sign
; and do the division
ldx ptr1+1 ; Load high byte of result
; Adjust the sign of the result. tmp1 contains the high byte of the left
; operand, tmp2 contains the high byte of the right operand.
lda tmp1
eor tmp2
bpl Pos ; Jump if sign of result positive
; Result is negative
lda ptr1 ; Load low byte of result
jmp negax ; Adjust the sign
; Result is positive
Pos: lda ptr1 ; Load low byte of result
rts
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