Strength ReductionInteger division by a Power of 2

• Untuned

IL = 0

DO I=1,ARRAY_SIZE

DO J=1,ARRAY_SIZE

IL = IL + A(J)/2

ENDDO

ILL(I) = IL

ENDDO

• Tuned

IL = 0

ILL = 0

DO I=1,ARRAY_SIZE

DO J=1,ARRAY_SIZE

IL = IL + ISHFT(A(J),-1)

ENDDO

ILL(I) = IL

ENDDO

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