10
Assuming that R0 is a constant zero, as in the example in the last tutorial
(I'll also accept CLR Rn) (also, various spellings of "MOV#" are fine, and
I'll also accept an immediate add instruction):
MOV# 1001, R1
MOV# 1, R2
ADD R0, R0, R3 ; (R3 <- 0)
LOOP: SUB R1, R2, R1
BGT LOOP
ADD R3, R1, R3 ; (delayed branch slot)
HALT
The result will be in R3.
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