53 lines
603 B
ArmAsm
53 lines
603 B
ArmAsm
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.define Sri4, Sru4
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! The subroutine Sri4 shifts a signed fourbyte integer to the
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! right n times
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! N is in register X.
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! The subroutine Sru4 shifts an unsigned fourbyte integer to the
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! right n times.
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Sru4:
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txa
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tay
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bne 1f
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rts
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1: jsr Pop
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stx ARTH
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sta ARTH+1
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jsr Pop
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stx ARTH+2
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jmp 2f
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Sri4:
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txa
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tay
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bne 1f
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rts
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1: jsr Pop
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stx ARTH
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sta ARTH+1
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jsr Pop
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stx ARTH+2
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tax
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bmi 1f
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2: lsr a
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ror ARTH+2
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ror ARTH+1
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ror ARTH
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dey
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bne 2b
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beq 4f
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1: sec
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ror a
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ror ARTH+2
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ror ARTH+1
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ror ARTH
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3: dey
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bne 1b
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4: ldx ARTH+2
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jsr Push
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lda ARTH+1
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ldx ARTH
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jmp Push
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