; ELEC 5200 - MIPS CPU TEST PROGRAM 

          org 	 00000000h
main:     jal      arith_test      ; logic/shift test 
end:      j        end             ; effectively halt machine 

; arith_test - arithmetic operation: D = A + B - C  
;              all numbers are 32-bit 2's complement integers 

arith_test:
          ori       $2, $0, 1           ; loop counter = 2 in r2 
          lui       $29, 1000h          ; point to data segment
          ori       $29, $29, 60h       ; point to A 
a_loop:   lw        $5, 0($29)          ; load A 
          lw        $6, 8($29)          ; load B 
          add       $5, $6, $5          ; A+B 
          lw        $7, 16($29)         ; load C 
          sub       $5, $5, $7          ; A+B-C 
          sw        $5, 24($29)         ; store result at D
          or        $5, $29, $6         ; test logical OR
          and       $5, $5, $7          ; test logical AND
          slt       $4, $5, $29         ; test slt
          sw        $5, 32($29)         ; store logical result at E
          addi      $2, $2, -1          ; loop counter 
          slti      $20, $2, 0          ; check loop counter 
          addi      $29, $29, 4         ; next data elements 
          beq       $20, $0, a_loop     ; branch
          jr        $31                 ; return 

; Test Data: Keep on word boundaries (all 32-bit words)
; NOTE: Given 1K-word memory ignores address bits A31-A13

	  org	    10000060h
A:      dd        5, -65
B:      dd        -34, 3
C:      dd        3, -70
D:      dd        0, 0
E:      dd        0, 0
	end