43 lines
499 B
ArmAsm
43 lines
499 B
ArmAsm
.define .sbi4
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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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! Subtract two 32 bits signed or unsigned integers.
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! Expects operands on stack
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! Yields result on stack
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.sbi4:
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pop h
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shld .retadr
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mov h,b
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mov l,c
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shld .bcreg
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lxi h,0
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dad sp !now hl points to the first operand
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mov d,h
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mov e,l
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inx d
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inx d
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inx d
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inx d !and de points to the second.
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mvi b,4
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xra a
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1: ldax d
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sbb m
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stax d
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inx d
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inx h
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dcr b
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jnz 1b
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sphl
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lhld .bcreg
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mov b,h
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mov c,l
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lhld .retadr
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pchl
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