2000-10-25 19:53:22 +00:00
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;
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; Ullrich von Bassewitz, 25.10.2000
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;
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; CC65 runtime: Decrement the stackpointer by value in y
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;
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.export subysp
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.importzp sp, tmp1
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.proc subysp
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sty tmp1 ; Save the value
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lda sp ; Get lo byte
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sec
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sbc tmp1 ; Subtract y value
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sta sp ; Put result back
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bcs @L1
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dec sp+1
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2001-03-24 16:15:01 +00:00
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@L1: rts ; Done
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2000-10-25 19:53:22 +00:00
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.endproc
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2001-03-24 16:15:01 +00:00
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