/*
	This C language subroutine computes the 
	subtrahend of two floating point matricies.

		     
	z(i,j) = x(i,j) - y(i,j)
	
	
	The Run Time Library for the C Language.

	Gordon A. Sterling	(617) 461 - 3076
	DSP Development Tools Engineering

	Created on 5/25/90
	Updated on 5/94 by AS
	Updated on 1/95 by AS - separated by polymorphic functions

	#include <matrix.h>			   <Header>
	float matsub(float z[][], float x[][], float y[][], int r, int s);<Prototype>
*/

#include "lib_glob.h"
#include "mat_glob.h"

.SEGMENT/CODE	Code_Space_Name;
.FILE 		RTL_FILENAME;

.GLOBAL		___matsubPPD;

___matsubPPD:	
sub_core:	readparam4(R1);
	    	readparam5(R2);

ppd_sub:	dm_mdf=pma_i;
		R0=R1-1, dm_ptr=R12;		/*Test for vector*/
		IF EQ R2=PASS R1, R1=R2;	/*If so, switch regs*/
		R1=R1-1, pma_i=R8;
		IF EQ JUMP (PC, ppd_one);	/*Single point!*/
		R8=PASS R4, pm_ptr=R4;
		LCNTR=R2, DO ppd_sub_row UNTIL LCE;
			R2=DM(dm_ptr, dm_1), R4=PM(pma_i, pm_1);
			LCNTR=R1, DO ppd_sub_col UNTIL LCE;
				F0=F4-F2, R2=DM(dm_ptr, dm_1), R4=PM(pma_i, pm_1);
ppd_sub_col:			F0=F4-F2, PM(pm_ptr,pm_1)=R0;
ppd_sub_row:		PM(pm_ptr,pm_1)=R0;
ppd_done:	
		pma_i=dm_mdf;

finish_up:	R0=PASS R8, FETCH_RETURN	/*Set ptr for return*/

restore_state:	RETURN (DB);
		RESTORE_STACK
		RESTORE_FRAME

ppd_one:	R2=DM(dm_ptr, dm_1), R4=PM(pma_i, pm_1);
		JUMP (PC, finish_up) (DB);
		F0=F4-F2, pma_i=dm_mdf;
		PM(pm_ptr, pm_1)=R0;

.ENDSEG;