29 lines
419 B
ArmAsm
29 lines
419 B
ArmAsm
.define Sli2
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.sect .text
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.sect .rom
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.sect .data
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.sect .bss
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.sect .text
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! This subroutine shifts a signed or unsigned interger to the
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! left n times.
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! N is in register X.
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! The returned value is in registerpair AX.
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Sli2:
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txa
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bne 1f
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jmp Pop ! zero shift, return input
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1: tay
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jsr Pop ! get integer
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stx Ytmp ! save lowbyte
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2: asl Ytmp
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rol a ! shift left
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dey
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bne 2b
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ldx Ytmp ! get lowbyte
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rts
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