38 lines
571 B
ArmAsm
38 lines
571 B
ArmAsm
;
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; 2023, Rumbledethumps
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;
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; CC65 will promote variadic char arguments to int. It will not demote longs.
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; int __cdecl__ xreg(char device, char channel, unsigned char address, ...);
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.export _xreg
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.importzp c_sp
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.import addysp, _ria_call_int
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.include "rp6502.inc"
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.code
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.proc _xreg
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; save variadic size in X
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tya
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tax
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@copy: ; copy stack
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dey
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lda (c_sp),y
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sta RIA_XSTACK
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tya
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bne @copy
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; recover variadic size and move c_sp
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txa
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tay
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jsr addysp
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; run RIA operation
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lda #RIA_OP_XREG
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jmp _ria_call_int
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.endproc
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