2000-05-28 13:40:48 +00:00
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; Ullrich von Bassewitz, 05.08.1998
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; CC65 runtime: sub ints
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.export tossuba0, tossubax
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2000-11-27 23:37:53 +00:00
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.import addysp1
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2000-05-28 13:40:48 +00:00
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.importzp sp, ptr1
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;
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; AX = TOS - AX
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;
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tossuba0:
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ldx #0
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tossubax:
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sta ptr1
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stx ptr1+1
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2000-11-27 23:37:53 +00:00
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.ifpc02
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lda (sp),y ; Get lo byte
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ldy #1 ; Hi index
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.else
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ldy #0
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lda (sp),y ; Lo byte
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iny ; Hi index
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.endif
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sec
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2000-05-28 13:40:48 +00:00
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sbc ptr1
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sta ptr1 ; save lo byte
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lda (sp),y
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sbc ptr1+1
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tax
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lda ptr1
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jmp addysp1 ; drop TOS, set condition codes
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