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! { dg-do run }
module e_52_2_mod
contains
subroutine init (v1, v2, N)
integer :: i, N
real :: v1(N), v2(N)
do i = 1, N
v1(i) = i + 2.0
v2(i) = i - 3.0
end do
end subroutine
subroutine init_again (v1, v2, N)
integer :: i, N
real :: v1(N), v2(N)
do i = 1, N
v1(i) = i - 3.0
v2(i) = i + 2.0
end do
end subroutine
subroutine check (p, N)
integer :: i, N
real, parameter :: EPS = 0.00001
real :: diff, p(N)
do i = 1, N
diff = p(i) - (i * i + (i + 2.0) * (i - 3.0))
if (diff > EPS .or. -diff > EPS) call abort
end do
end subroutine
logical function maybe_init_again (v, N)
real :: v(N)
integer :: i, N
do i = 1, N
v(i) = i
end do
maybe_init_again = .true.
end function
subroutine vec_mult (p, v1, v2, N)
real :: p(N), v1(N), v2(N)
integer :: i, N
logical :: changed
call init (v1, v2, N)
!$omp target data map(to: v1, v2) map(from: p)
!$omp target
!$omp parallel do
do i = 1, N
p(i) = v1(i) * v2(i)
end do
!$omp end target
changed = maybe_init_again (v1, N)
!$omp target update if(changed) to(v1(:N))
changed = maybe_init_again (v2, N)
!$omp target update if(changed) to(v2(:N))
!$omp target
!$omp parallel do
do i = 1, N
p(i) = p(i) + v1(i) * v2(i)
end do
!$omp end target
!$omp end target data
call check (p, N)
end subroutine
end module
program e_52_2
use e_52_2_mod, only : vec_mult
integer :: n
real, pointer :: p(:), v1(:), v2(:)
n = 1000
allocate (p(n), v1(n), v2(n))
call vec_mult (p, v1, v2, n)
deallocate (p, v1, v2)
end program
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