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22 lines
522 B
Fortran
22 lines
522 B
Fortran
! Compute the dot product of two vectors w/ 4 entries with explicit loops.
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! Try changing the target architecture to AVX (-mavx)
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! and enabling optimisation (-O3) and compare the results.
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real function dot_prod(a, b)
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implicit none
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real, intent(in), dimension(4) :: a, b
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real, dimension(4) :: temp
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integer :: i
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do i = 1, 4
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temp(i) = a(i) * b(i)
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end do
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dot_prod = 0.
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do i = 1,4
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dot_prod = dot_prod + temp(i)
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end do
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return
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end function dot_prod
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