#ifdef show_comments
! These comments are not intended to be retained during preprocessing; i.e. do not define "show_comments"
!!----------------------------------------------------------------------
!! NEMO/OCE 4.0 , NEMO Consortium (2018)
!! Software governed by the CeCILL license (see ./LICENSE)
!!----------------------------------------------------------------------
! This header file contains preprocessor definitions and macros used in the do-loop substitutions introduced
! between version 4.0 and 4.2. The primary aim of these macros is to assist in future applications of tiling
! to improve performance. This is expected to be achieved by alternative versions of these macros in selected
! locations. The initial introduction of these macros simply replaces all identifiable nested 2D- and 3D-loops
! with single line statements (and adjusts indenting accordingly). Do loops are identifiable if they comform
! to either:
!                                       DO jk = ....
!   DO jj = ....                           DO jj = ...
!      DO ji = ....                           DO ji = ...
!         .                   OR                 .  
!         .                                      .
!     END DO                                  END DO
!   END DO                                 END DO
!                                       END DO
! and white-space variants thereof.
!
! Additionally, only loops with recognised jj and ji loops limits are treated; these are:
! Lower limits of 1, 2 or fs_2
! Upper limits of jpi, jpim1 or fs_jpim1 (for ji) or jpj, jpjm1 or fs_jpjm1 (for jj)
!
! The macro naming convention takes the form: DO_2D_BT_LR where: 
!   B is the Bottom offset from the PE's inner domain;
!   T is the Top    offset from the PE's inner domain;
!   L is the Left   offset from the PE's inner domain;
!   R is the Right  offset from the PE's inner domain
!
! So, given an inner domain of 2,jpim1 and 2,jpjm1, a typical example would replace:
! 
!   DO jj = 2, jpj
!      DO ji = 1, jpim1
!         .
!         .
!      END DO
!   END DO
!
! with:
!
!   DO_2D_01_10
!      .
!      .
!   END_2D
! 
! similar conventions apply to the 3D loops macros. jk loop limits are retained through macro arguments and are not restricted. This
! includes the possibility of strides for which an extra set of DO_3DS macros are defined.
!
! In the definitions below the inner PE domain is defined by start indices of (kIs, kJs) and end indices of (kIe, KJe)
!
#endif
#define kIs     2
#define kJs     2
#define kIsm1   1
#define kJsm1   1

#define kIe     jpim1
#define kJe     jpjm1
#define kIep1   jpi
#define kJep1   jpj

#define DO_2D_00_00   DO jj = kJs, kJe   ;   DO ji = kIs, kIe
#define DO_2D_00_01   DO jj = kJs, kJe   ;   DO ji = kIs, kIep1
#define DO_2D_00_10   DO jj = kJs, kJe   ;   DO ji = kIsm1, kIe
#define DO_2D_00_11   DO jj = kJs, kJe   ;   DO ji = kIsm1, kIep1
 
#define DO_2D_01_00   DO jj = kJs, kJep1   ;   DO ji = kIs, kIe
#define DO_2D_01_01   DO jj = kJs, kJep1   ;   DO ji = kIs, kIep1
#define DO_2D_01_10   DO jj = kJs, kJep1   ;   DO ji = kIsm1, kIe
#define DO_2D_01_11   DO jj = kJs, kJep1   ;   DO ji = kIsm1, kIep1
 
#define DO_2D_10_00   DO jj = kJsm1, kJe   ;   DO ji = kIs, kIe
#define DO_2D_10_10   DO jj = kJsm1, kJe   ;   DO ji = kIsm1, kIe
#define DO_2D_10_11   DO jj = kJsm1, kJe   ;   DO ji = kIsm1, kIep1
 
#define DO_2D_11_00   DO jj = kJsm1, kJep1   ;   DO ji = kIs, kIe
#define DO_2D_11_01   DO jj = kJsm1, kJep1   ;   DO ji = kIs, kIep1
#define DO_2D_11_10   DO jj = kJsm1, kJep1   ;   DO ji = kIsm1, kIe
#define DO_2D_11_11   DO jj = kJsm1, kJep1   ;   DO ji = kIsm1, kIep1


#define DO_3D_00_00(ks,ke)   DO jk = ks, ke   ;   DO_2D_00_00
#define DO_3D_00_10(ks,ke)   DO jk = ks, ke   ;   DO_2D_00_10
 
#define DO_3D_01_01(ks,ke)   DO jk = ks, ke   ;   DO_2D_01_01
 
#define DO_3D_10_00(ks,ke)   DO jk = ks, ke   ;   DO_2D_10_00
#define DO_3D_10_10(ks,ke)   DO jk = ks, ke   ;   DO_2D_10_10
#define DO_3D_10_11(ks,ke)   DO jk = ks, ke   ;   DO_2D_10_11
 
#define DO_3D_11_11(ks,ke)   DO jk = ks, ke   ;   DO_2D_11_11

#define DO_3DS_00_00(ks,ke,ki)   DO jk = ks, ke, ki   ;   DO_2D_00_00
#define DO_3DS_01_01(ks,ke,ki)   DO jk = ks, ke, ki   ;   DO_2D_01_01
#define DO_3DS_10_10(ks,ke,ki)   DO jk = ks, ke, ki   ;   DO_2D_10_10
#define DO_3DS_11_11(ks,ke,ki)   DO jk = ks, ke, ki   ;   DO_2D_11_11

#define END_2D   END DO   ;   END DO
#define END_3D   END DO   ;   END DO   ;   END DO