compiler: ensure inf is treated as non-strict direction

Author: mloubout

devito/ir/support/basic.py

@@ -351,7 +351,7 @@ def distance(self, other):
                     # E.g., `self=R<f,[x + 2]>` and `other=W<f,[i + 1]>`
                     # E.g., `self=R<f,[x]>`, `other=W<f,[x + 1]>`,
                     #       `self.itintervals=(x<0>,)`, `other.itintervals=(x<1>,)`
-                    return vinf(ret)
+                    return v_undef(ret)
             except AttributeError:
                 # E.g., `self=R<f,[cy]>` and `self.itintervals=(y,)` => `sai=None`
                 pass
@@ -413,10 +413,12 @@ def distance(self, other):
                 # E.g., `self=R<f,[x, y]>`, `sai=time`,
                 #       `self.itintervals=(time, x, y)`, `n=0`
                 continue
+            elif not sai or not oai:
+                return v_undef(ret, val=S.NaN)
             else:
                 # E.g., `self=R<u,[t+1, ii_src_0+1, ii_src_1+2]>`, `fi=p_src`,
                 # and `n=1`
-                return vinf(ret)
+                return v_undef(ret)
 
         n = len(ret)
 
@@ -640,7 +642,11 @@ def cause(self):
         """Return the findex causing the dependence."""
         for i, j in zip(self.findices, self.distance):
             try:
-                if j > 0:
+                # If j is S.Infinity, then the direction was not defined
+                # so we treat it as non cause.
+                if j is S.NaN:
+                    continue
+                elif j > 0:
                     return i._defines
             except TypeError:
                 # Conservatively assume this is an offending dimension
@@ -1353,8 +1359,8 @@ def is_regular(self):
 
 # *** Utils
 
-def vinf(entries):
-    return Vector(*(entries + [S.Infinity]))
+def v_undef(entries, val=S.Infinity):
+    return Vector(*(entries + [val]))
 
 
 def retrieve_accesses(exprs, **kwargs):

devito/passes/iet/mpi.py

@@ -530,8 +530,11 @@ def _semantical_eq_loc_indices(hsf0, hsf1):
 
         # Special case: they might be syntactically different, but semantically
         # equivalent, e.g., `t0` and `t1` with same modulus
-        if v0.modulo == v1.modulo == 1:
-            continue
+        try:
+            if v0.modulo == v1.modulo == 1:
+                continue
+        except AttributeError:
+            return False
 
         return False
 

devito/types/dense.py

@@ -16,7 +16,7 @@
 from devito.logger import debug, warning
 from devito.mpi import MPI
 from devito.parameters import configuration
-from devito.symbolics import FieldFromPointer, normalize_args
+from devito.symbolics import FieldFromPointer, normalize_args, IndexedPointer
 from devito.finite_differences import Differentiable, generate_fd_shortcuts
 from devito.finite_differences.tools import fd_weights_registry
 from devito.tools import (ReducerMap, as_tuple, c_restrict_void_p, flatten,
@@ -719,7 +719,7 @@ def _C_make_index(self, dim, side=None):
     @memoized_meth
     def _C_get_field(self, region, dim, side=None):
         """Symbolic representation of a given data region."""
-        ffp = lambda f, i: FieldFromPointer("%s[%d]" % (f, i), self._C_symbol)
+        ffp = lambda f, i: IndexedPointer(FieldFromPointer("%s" % f, self._C_symbol), i)
         if region is DOMAIN:
             offset = ffp(self._C_field_owned_ofs, self._C_make_index(dim, LEFT))
             size = ffp(self._C_field_domain_size, self._C_make_index(dim))

tests/test_operator.py

@@ -35,7 +35,9 @@
 from devito.passes.iet.languages.C import CDataManager
 from devito.symbolics import ListInitializer, indexify, retrieve_indexed
 from devito.tools import flatten, powerset, timed_region
-from devito.types import Array, Barrier, CustomDimension, Indirection, Scalar, Symbol
+from devito.types import (
+    Array, Barrier, CustomDimension, Indirection, Scalar, Symbol, ConditionalDimension
+)
 
 
 def dimify(dimensions):
@@ -2034,6 +2036,23 @@ def test_2194_v2(self, eqns, expected, exp_trees, exp_iters):
         op.apply()
         assert(np.all(u.data[:] == expected[:]))
 
+    def test_pseudo_time_dep(self):
+        """
+        Test taht a data dependency through a field is correctly
+        ignore when nor direction dependent
+        """
+        grid = Grid((11, 11))
+        ct = ConditionalDimension(name='ct', parent=grid.time_dim, factor=2)
+        f = TimeFunction(name='f', grid=grid, time_order=1)
+        g = Function(name='g', grid=grid)
+
+        eq = [Eq(f.backward, div(f) + 1),
+              Eq(g, g + f.symbolic_shape[1], implicit_dims=ct),
+              Eq(g, g + 1, implicit_dims=ct)]
+        op = Operator(eq)
+
+        assert_structure(op, ['t,x,y', 't', 't,x,y'], 't,x,y,x,y')
+
 
 class TestInternals: