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Argument	char		 int		long
Number	     1-byte ptr       2-byte ptr	float		 generic ptr 	--------------------------------------------------------------------------------------
   1		R7		R6 & R7		R4-R7		    R1-R3 
   2		R5		R4 & R5		R4-R7		    R1-R3 
   3		R3		R2 & R3			            R1-R3 
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