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; divt.s
;
; 2002-10-22, Greg King
;
; This signed-division function returns both the quotient and the remainder,
; in this structure:
;
; typedef struct {
; int rem, quot;
; } div_t;
;
; div_t __fastcall__ div (int numer, int denom);
;
.export _div
.import tosdivax, negax
.importzp sreg, ptr1, tmp1
_div: jsr tosdivax ; Division-operator does most of the work
ldy sreg ; low byte remainder from sreg
sta sreg ; store low byte quotient to sreg
lda sreg+1 ; high byte remainder from sreg
stx sreg+1 ; store high byte quotient to sreg
tax ; high byte remainder to x
tya ; low byte remainder to a
; Adjust the sign of the remainder.
; It must be the same as the sign of the dividend.
;
bit tmp1 ; Load high-byte of left argument
bpl Pos ; Jump if sign-of-result is positive
jmp negax ; Result is negative, adjust the sign
Pos: rts
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