ISA cont. #

RISC – reduced instruction set computer #

Some RISC style assembly to calculate \( A = B \cdot (C + D) \)

LD R1, (C)      ; R1 <- M[C]
LD R2, (D)      ; R2 <- M[D]
ADD R3, R1, R2  ; R3 <- R1 + R2
LD R4, (B)      ; R4 <- M[B]
MUL R5, R3, R4  ; R5 <- R3 * R4
ST (A), R5      ; M[A] <- R5

Design example: Accumulator ISA #