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;
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; Ullrich von Bassewitz, 05.08.1998
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;
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; int abs (int x);
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; and
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; CC65 runtime: negation on ints
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;
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.export negax
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.export _abs
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_abs: cpx #$00 ; Test hi byte
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bpl L1 ; Don't touch if positive
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negax: clc
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eor #$FF
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adc #1
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pha
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txa
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eor #$FF
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|
adc #0
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|
tax
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|
pla
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L1: rts
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|