; Performance
; A looper program for timing measurements

; for i := 0 to n
;   for j := 0 to m
;      nop
;   write "a"

; R1   constant 1
; R2   n  number of iterations for outer loop
; R3   m  number of iterations for inner loop
; R4   i, outer loop counter:  0 ... n
; R5   j, inner loop counter   0 ... m
; R6   constant 2, trap write code
; R7   address of string to write
; R8   number of characters to write

     lea    R1,1[R0]      ; R1 = constant 1, loop increment
     load   R2,n[R0]      ; R2 = outer loop limit
     load   R3,m[R0]      ; R3 = inner loop limit
     lea    R6,2[R0]      ; R6 := 2 = trap write code
     lea    R7,out[R0]    ; R7 = address of output string
     lea    R8,1[R0]      ; R8 = length of output string

     add    R4,R0,R0      ; i := 0, initialize outer loop counter
outerloop
     cmp    R4,R2         ; i >= n
     jumpge done[R0]      ; if i >= n then goto done

     add    R5,R0,R0      ; j := 0, initialize inner loop counter
innerloop
     cmp    R5,R3         ; j >= m
     jumpge innerdone[R0] ; if j >= m then goto innerdone
     add    R5,R5,R1      ; j := j + 1
     jump   innerloop[R0] ; goto innerloop

innerdone
     trap   R6,R7,R8      ; write "a"
     add    R4,R4,R1      ; i := i + 1
     jump   outerloop[R0] ; goto outer loop

done
     trap   R0,R0,R0      ; terminate

n    data    10          ; outer loop iterations
m    data  1000          ; inner loop iterations
out  data    97          ; character code for 'a'