1 program main 2 use omp_lib 3 use openacc 4 implicit none 5 6 real,allocatable:: v1(:) 7 integer length, idx 8 9 call acc_set_device_num(2,acc_device_nvidia) 10 length = 1024!*1024!*1024 11 allocate(v1(length)) 12 v1(1:length) = 0.0 13 !使用data语句，将数据copy到device上 14 !$acc data copy(v1(1:length)) 15 call add1(v1, length) !子程序在device上执行 16 17 !print只能cpu实行，所以讲数据update到cpu上 18 !$acc update host(v1(1:5)) 19 print*, "v1(1) = ", v1(1:5) 20 !下面是在cpu上执行 21 do idx = 1,length 22 v1(idx) = v1(idx) + 10 23 enddo 24 print*, "v1(1) = ", v1(1:5) !直接打印出cpu上的结果 25 26 !将cpu上的执行结果update到device上 27 !$acc update device(v1(1:5)) 28 call add1(v1, length) 29 30 !上面子程序在device上执行完，update到本地输出 31 !$acc update host(v1(1:5)) 32 print*, "v1(1) = ", v1(1:5) 33 !结束 34 !$acc end data 35 36 deallocate(v1) 37 38 end program 39 40 subroutine add1(vec, length) 41 use openacc 42 implicit none 43 integer, intent(in)::length 44 real, intent(inout) :: vec(1:length) 45 integer idx 46 !$acc parallel loop present(vec(1:length)) 47 do idx = 1, length 48 vec(idx) = vec(idx) + idx 49 enddo 50 end subroutine