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28 lines
600 B
ArmAsm
28 lines
600 B
ArmAsm
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; Ullrich von Bassewitz, 2011-07-10
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; CC65 library: 16x8 => 32 unsigned multiplication
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;
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.export _cc65_umul16x8r32
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.import umul8x16r24, popax
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.include "zeropage.inc"
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;---------------------------------------------------------------------------
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; 16x8 => 32 unsigned multiplication routine. We use 8x16 => 24 and clear
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; the high byte of the result
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.proc _cc65_umul16x8r32
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sta ptr1
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lda #0
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sta sreg+1 ; Clear high byte of result
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jsr popax
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jmp umul8x16r24
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.endproc
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