Add support for scheme subcycling

scripts/common.py

@@ -22,6 +22,7 @@
 CCPP_ERROR_FLAG_VARIABLE = 'ccpp_error_flag'
 CCPP_ERROR_MSG_VARIABLE  = 'ccpp_error_message'
 CCPP_LOOP_COUNTER        = 'ccpp_loop_counter'
+CCPP_LOOP_EXTENT         = 'ccpp_loop_extent'
 CCPP_BLOCK_NUMBER        = 'ccpp_block_number'
 CCPP_BLOCK_COUNT         = 'ccpp_block_count'
 CCPP_BLOCK_SIZES         = 'ccpp_block_sizes'

scripts/mkstatic.py

@@ -14,7 +14,7 @@
 
 from common import encode_container
 from common import CCPP_STAGES
-from common import CCPP_ERROR_FLAG_VARIABLE, CCPP_ERROR_MSG_VARIABLE, CCPP_LOOP_COUNTER
+from common import CCPP_ERROR_FLAG_VARIABLE, CCPP_ERROR_MSG_VARIABLE, CCPP_LOOP_COUNTER, CCPP_LOOP_EXTENT
 from common import CCPP_BLOCK_NUMBER, CCPP_BLOCK_COUNT, CCPP_BLOCK_SIZES, CCPP_INTERNAL_VARIABLES
 from common import CCPP_HORIZONTAL_DIMENSION, CCPP_HORIZONTAL_LOOP_EXTENT
 from common import FORTRAN_CONDITIONAL_REGEX_WORDS, FORTRAN_CONDITIONAL_REGEX
@@ -900,6 +900,10 @@ def write(self, metadata_request, metadata_define, arguments):
 
         # First get target names of standard CCPP variables for subcycling and error handling
         ccpp_loop_counter_target_name = metadata_request[CCPP_LOOP_COUNTER][0].target
+        if CCPP_LOOP_EXTENT in metadata_request.keys():
+            ccpp_loop_extent_target_name = metadata_request[CCPP_LOOP_EXTENT][0].target
+        else:
+            ccpp_loop_extent_target_name = None
         ccpp_error_flag_target_name = metadata_request[CCPP_ERROR_FLAG_VARIABLE][0].target
         ccpp_error_msg_target_name = metadata_request[CCPP_ERROR_MSG_VARIABLE][0].target
         #
@@ -930,10 +934,8 @@ def write(self, metadata_request, metadata_define, arguments):
             conditionals = {}
             #
             for subcycle in self._subcycles:
-                if subcycle.loop > 1 and ccpp_stage == 'run':
-                    body += '''
-      associate(cnt => {loop_var_name})
-      do cnt=1,{loop_cnt}\n\n'''.format(loop_var_name=ccpp_loop_counter_target_name,loop_cnt=subcycle.loop)
+                subcycle_body = ''
+                # Call all schemes
                 for scheme_name in subcycle.schemes:
                     # actions_before and actions_after capture operations such
                     # as unit conversions, transformations that have to happen
@@ -1348,18 +1350,47 @@ def write(self, metadata_request, metadata_define, arguments):
         return
       end if
 '''.format(target_name_flag=ccpp_error_flag_target_name, target_name_msg=ccpp_error_msg_target_name, subroutine_name=subroutine_name)
-                    body += '''
+                    subcycle_body += '''
       {subroutine_call}
       {error_check}
     '''.format(subroutine_call=subroutine_call, error_check=error_check)
 
                     module_use += '   use {m}, only: {s}\n'.format(m=module_name, s=subroutine_name)
 
-                if subcycle.loop > 1 and ccpp_stage == 'run':
-                    body += '''
+                # If this subcycle calls any schemes, i.e. has any variables registered
+                # that need to be passed to the group for this stage, then handle the
+                # subcycle loops by prepending/appending the necessary code to subcycle_body
+                subcycle_body_prefix = '''
+      ! Start of next subcycle
+'''
+                subcycle_body_suffix = ''
+                if self.parents[ccpp_stage]:
+                    # Set subcycle loop extent if requested by any scheme
+                    if ccpp_loop_extent_target_name and ccpp_stage == 'run':
+                        subcycle_body_prefix += '''
+      ! Set loop extent variable for the following subcycle
+      {loop_extent_var_name} = {loop_cnt_max}\n\n'''.format(loop_extent_var_name=ccpp_loop_extent_target_name,
+                                                                                   loop_cnt_max=subcycle.loop)
+                    elif ccpp_loop_extent_target_name:
+                        subcycle_body_prefix += '''
+      ! Set loop extent variable for the following subcycle
+      {loop_extent_var_name} = 1\n\n'''.format(loop_extent_var_name=ccpp_loop_extent_target_name)
+                    # Create subcycle (Fortran do loop) if needed
+                    if subcycle.loop > 1 and ccpp_stage == 'run':
+                        subcycle_body_prefix += '''
+      associate(cnt => {loop_var_name})
+      do cnt=1,{loop_cnt_max}\n\n'''.format(loop_var_name=ccpp_loop_counter_target_name,
+                                                        loop_cnt_max=subcycle.loop)
+                        subcycle_body_suffix += '''
       end do
       end associate
 '''
+                    else:
+                        subcycle_body_prefix += '''
+      {loop_var_name} = 1\n'''.format(loop_var_name=ccpp_loop_counter_target_name)
+
+                # Add this subcycle's Fortran body to the group body
+                body += subcycle_body_prefix + subcycle_body + subcycle_body_suffix
 
             # Get list of arguments, module use statement and variable definitions for this subroutine (=stage for the group)
             (self.arguments[ccpp_stage], sub_module_use, sub_var_defs) = create_arguments_module_use_var_defs(

src/ccpp_types.F90

@@ -30,6 +30,7 @@ module ccpp_types
 
     !> @var The default loop counter indicating outside of a subcycle loop
     integer, parameter :: CCPP_DEFAULT_LOOP_CNT = -999
+    integer, parameter :: CCPP_DEFAULT_LOOP_MAX = -999
 
     !> @var The default values for block and thread numbers indicating invalid data
     integer, parameter :: CCPP_DEFAULT_BLOCK_AND_THREAD_NUMBER = -999
@@ -51,6 +52,7 @@ module ccpp_types
        integer                                             :: errflg = 0
        character(len=512)                                  :: errmsg = ''
        integer                                             :: loop_cnt = CCPP_DEFAULT_LOOP_CNT
+       integer                                             :: loop_max = CCPP_DEFAULT_LOOP_MAX
        integer                                             :: blk_no = CCPP_DEFAULT_BLOCK_AND_THREAD_NUMBER
        integer                                             :: thrd_no = CCPP_DEFAULT_BLOCK_AND_THREAD_NUMBER
 

src/ccpp_types.meta

@@ -41,6 +41,12 @@
   units = index
   dimensions = ()
   type = integer
+[loop_max]
+  standard_name = ccpp_loop_extent
+  long_name = loop extent for subcycling loops in CCPP
+  units = count
+  dimensions = ()
+  type = integer
 [blk_no]
   standard_name = ccpp_block_number
   long_name = number of block for explicit data blocking in CCPP