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<h1> words/log2.asm </h1> |
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<pre> |
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; ( n1 -- n2 ) Arithmetics |
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; R( -- ) |
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; logarithm base 2 or highest set bitnumber |
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VE_LOG2: |
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.db $04, "log2",0 |
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.dw VE_HEAD |
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.set VE_HEAD = VE_LOG2 |
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XT_LOG2: |
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.dw PFA_LOG2 |
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PFA_LOG2: |
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movw zl, tosl |
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clr tosh |
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ldi temp0, 16 |
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mov tosl, temp0 |
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PFA_LOG2_1: |
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dec tosl |
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brmi PFA_LOG2_2 ; wrong data |
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lsl zl |
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rol zh |
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brcc PFA_LOG2_1 |
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rjmp DO_NEXT |
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PFA_LOG2_2: |
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dec tosh |
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rjmp DO_NEXT |
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