2009-11-04 19:41:54 +00:00
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; Ullrich von Bassewitz, 2009-11-04
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; CC65 library: 32by16 => 16 signed division
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;
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2013-05-09 11:56:54 +00:00
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.export _cc65_idiv32by16r16
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2009-11-04 19:41:54 +00:00
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.import idiv32by16r16, incsp4
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.include "zeropage.inc"
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;---------------------------------------------------------------------------
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; 32by16 division.
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.proc _cc65_idiv32by16r16
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pha ; Save rhs
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; Copy from stack to zeropage. This assumes ptr1 and ptr2 are adjacent.
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ldy #3
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@L1: lda (sp),y
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sta ptr1,y
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dey
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bpl @L1
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lda #4
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clc
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adc sp
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sta sp
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bcc @L2
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inc sp+1
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@L2: pla ; Old rhs
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jmp idiv32by16r16
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.endproc
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