diff --git a/loopy/codegen/loop.py b/loopy/codegen/loop.py
index 8ac963835ec12702f2010806d1d49062422318a2..ad80475c1d27f67b3df8a885f60dd96ff28efe6a 100644
--- a/loopy/codegen/loop.py
+++ b/loopy/codegen/loop.py
@@ -386,29 +386,41 @@ def generate_sequential_loop_dim_code(codegen_state, sched_index):
 
         _, loop_iname_idx = dom_and_slab.get_var_dict()[loop_iname]
 
+        impl_domain = isl.align_spaces(
+            codegen_state.implemented_domain,
+            dom_and_slab,
+            obj_bigger_ok=True,
+            across_dim_types=True
+            ).params()
+
         lbound = (
                 kernel.cache_manager.dim_min(
                     dom_and_slab, loop_iname_idx)
                 .gist(kernel.assumptions)
-                .gist(dom_and_slab.params())
+                .gist(impl_domain)
                 .coalesce())
         ubound = (
             kernel.cache_manager.dim_max(
                 dom_and_slab, loop_iname_idx)
             .gist(kernel.assumptions)
-            .gist(dom_and_slab.params())
+            .gist(impl_domain)
             .coalesce())
 
         # }}}
 
         # {{{ find implemented loop, build inner code
 
-        from loopy.isl_helpers import make_loop_bounds_from_pwaffs
+        from loopy.symbolic import pw_aff_to_pw_aff_implemented_by_expr
+        impl_lbound = pw_aff_to_pw_aff_implemented_by_expr(lbound)
+        impl_ubound = pw_aff_to_pw_aff_implemented_by_expr(ubound)
 
         # impl_loop may be overapproximated
+        from loopy.isl_helpers import make_loop_bounds_from_pwaffs
         impl_loop = make_loop_bounds_from_pwaffs(
                 dom_and_slab.space,
-                loop_iname, lbound, ubound)
+                loop_iname,
+                impl_lbound,
+                impl_ubound)
 
         for iname in moved_inames:
             dt, idx = impl_loop.get_var_dict()[iname]
@@ -431,13 +443,9 @@ def generate_sequential_loop_dim_code(codegen_state, sched_index):
 
         astb = codegen_state.ast_builder
 
-        zero = isl.PwAff.zero_on_domain(
-            isl.LocalSpace.from_space(
-                lbound.get_space()).domain())
-
         from loopy.symbolic import pw_aff_to_expr
 
-        if (ubound - lbound).plain_is_equal(zero):
+        if ubound.is_equal(lbound):
             # single-trip, generate just a variable assignment, not a loop
             inner = merge_codegen_results(codegen_state, [
                 astb.emit_initializer(
diff --git a/loopy/symbolic.py b/loopy/symbolic.py
index 430c651589939a1001432bd8db413cb5902b14a6..52fd6e57f92e7f9599a3a0fb4256f97347708303 100644
--- a/loopy/symbolic.py
+++ b/loopy/symbolic.py
@@ -1150,6 +1150,23 @@ def pw_aff_to_expr(pw_aff, int_ok=False):
 
     return expr
 
+
+def pw_aff_to_pw_aff_implemented_by_expr(pw_aff):
+    pieces = pw_aff.get_pieces()
+
+    rest = isl.Set.universe(pw_aff.space.params())
+    aff_set, aff = pieces[0]
+    impl_pw_aff = isl.PwAff.alloc(aff_set, aff)
+    rest = rest.intersect_params(aff_set.complement())
+
+    for aff_set, aff in pieces[1:-1]:
+        impl_pw_aff = impl_pw_aff.union_max(
+            isl.PwAff.alloc(aff_set, aff))
+        rest = rest.intersect_params(aff_set.complement())
+
+    _, aff = pieces[-1]
+    return impl_pw_aff.union_max(isl.PwAff.alloc(rest, aff)).coalesce()
+
 # }}}