39 lines
752 B
ArmAsm
39 lines
752 B
ArmAsm
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; Ullrich von Bassewitz, 2009-11-04
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; CC65 library: 32by16 => 16 unsigned division
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;
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.export _cc65_udiv32by16r16
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.import udiv32by16r16m, incsp4
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.importzp ptr1, ptr2, ptr3, sp
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;---------------------------------------------------------------------------
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; 32by16 division.
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.proc _cc65_udiv32by16r16
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sta ptr3
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stx ptr3+1 ; Store 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: jmp udiv32by16r16m
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.endproc
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