#2661 more tidying and removal of duplication

src/psyclone/domain/lfric/lfric_loop.py

@@ -931,8 +931,6 @@ def gen_mark_halos_clean_dirty(self, parent):
         # Set halo clean/dirty for all fields that are modified
         fields = self.unique_modified_args("gh_field")
 
-        sym_table = self.ancestor(InvokeSchedule).symbol_table
-
         # First set all of the halo dirty unless we are
         # subsequently going to set all of the halo clean
         for field in fields:
@@ -941,7 +939,7 @@ def gen_mark_halos_clean_dirty(self, parent):
             from psyclone.dynamo0p3 import HaloWriteAccess
             # The HaloWriteAccess class provides information about how the
             # supplied field is accessed within its parent loop
-            hwa = HaloWriteAccess(field, sym_table, self)
+            hwa = HaloWriteAccess(field, self)
             if not hwa.max_depth or hwa.dirty_outer:
                 # output set dirty as some of the halo will not be set to clean
                 if field.vector_size > 1:

src/psyclone/dynamo0p3.py

@@ -3916,8 +3916,7 @@ def _compute_halo_write_info(self):
                 f"Internal logic error. There should be at most one write "
                 f"dependence for a halo exchange. Found "
                 f"'{len(write_dependencies)}'")
-        return HaloWriteAccess(write_dependencies[0], self._symbol_table,
-                               parent=self)
+        return HaloWriteAccess(write_dependencies[0], parent=self)
 
     def required(self, ignore_hex_dep=False):
         '''Determines whether this halo exchange is definitely required
@@ -4509,13 +4508,13 @@ class HaloWriteAccess(HaloDepth):
 
     :param field: the field that we are concerned with.
     :type field: :py:class:`psyclone.dynamo0p3.DynArgument`
-    :param sym_table: the symbol table associated with the scoping region \
-                      that contains this halo access.
-    :type sym_table: :py:class:`psyclone.psyir.symbols.SymbolTable`
+    :param parent: the parent PSyIR node associated with the scoping region
+                   that contains this halo access.
+    :type parent: :py:class:`psyclone.psyir.nodes.Node`
 
     '''
-    def __init__(self, field, sym_table, parent):
-        HaloDepth.__init__(self, sym_table, parent)
+    def __init__(self, field, parent):
+        HaloDepth.__init__(self, parent)
         self._compute_from_field(field)
 
     @property
@@ -4537,17 +4536,18 @@ def clean_depth(self):
         '''
         Returns the depth to which this halo is clean following the write.
 
-        :returns:
-        :rtype:
+        :returns: PSyIR for the expression for the clean halo depth or None.
+        :rtype: :py:class:`psyclone.psyir.nodes.Node` | NoneType
 
         '''
         if self.var_depth:
             halo_depth = self.var_depth
         elif self.max_depth:
             # halo accesses(s) is/are to the full halo
             # depth (-1 if continuous)
-            halo_depth = Reference(self._symbol_table.lookup_with_tag(
-                "max_halo_depth_mesh"))
+            table = self._parent.scope.symbol_table
+            halo_depth = Reference(
+                table.lookup_with_tag("max_halo_depth_mesh"))
         else:
             return None
 
@@ -4557,7 +4557,6 @@ def clean_depth(self):
                 halo_depth.copy(), Literal("1", INTEGER_TYPE))
 
         sym_maths = SymbolicMaths.get()
-        from psyclone.psyir.nodes import Assignment, Schedule
         fake_assign = Assignment.create(
             Reference(DataSymbol("tmp", INTEGER_TYPE)),
             halo_depth)