33 lines
548 B
ArmAsm
33 lines
548 B
ArmAsm
.define Rmi2
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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 returns the remainder of a twobyte signed division.
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! The sign of the result is as specified in the emtest.
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Rmi2:
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ldy #0
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sty NBYTES ! for the sign of the result
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stx ARTH
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sta ARTH+1 ! first operand
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jsr Pop
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stx ARTH+2
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sta ARTH+3 ! second operand
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ldy #0
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sty UNSIGN ! its signed arithmetic
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jsr Div
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lsr ARTH+5
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ror ARTH+4 ! result must be shifted one time
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ldx ARTH+4
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lda ARTH+5
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ldy NBYTES
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beq 1f ! result must be positive
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jmp Ngi2
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1: rts
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