gcc/testsuite/gfortran.dg/loop_interchange_1.f90

   1 ! { dg-do compile }
   2 ! { dg-additional-options "-O -Wfrontend-loop-interchange" }
   3 PROGRAM TEST_DO_SPEED
   4   IMPLICIT NONE
   5
   6   REAL, ALLOCATABLE :: A(:,:,:), B(:,:,:), C(:,:,:)
   7   REAL :: TIC
   8   INTEGER :: T0, T1, T2
   9   INTEGER :: I, J, K
  10   INTEGER, PARAMETER :: L = 512, M = 512, N = 512
  11
  12   ALLOCATE( A(L,M,N), B(L,M,N), C(L,M,N) )
  13   CALL RANDOM_NUMBER(A)
  14   CALL RANDOM_NUMBER(B)
  15
  16   CALL SYSTEM_CLOCK( T0, TIC)
  17
  18   DO CONCURRENT( K=1:N, J=1:M, I=1:L) ! { dg-warning "Interchanging loops" }
  19     C(I,J,K) = A(I,J,K) +B(I,J,K)
  20   END DO
  21 END
  22