initial tests for value_Set_abstract_object widening merge

Author: jezhiggins

unit/Makefile

@@ -31,6 +31,7 @@ SRC += analyses/ai/ai.cpp \
        analyses/variable-sensitivity/value_set_abstract_object/compacting.cpp \
        analyses/variable-sensitivity/value_set_abstract_object/meet.cpp \
        analyses/variable-sensitivity/value_set_abstract_object/merge.cpp \
+       analyses/variable-sensitivity/value_set_abstract_object/widening_merge.cpp \
        analyses/variable-sensitivity/variable_sensitivity_test_helpers.cpp \
        ansi-c/max_malloc_size.cpp \
        ansi-c/type2name.cpp \

unit/analyses/variable-sensitivity/value_set_abstract_object/widening_merge.cpp

@@ -0,0 +1,97 @@
+/*******************************************************************\
+
+ Module: Unit tests for value_set_abstract_objectt::merge
+
+ Author: Jez Higgins.
+
+\*******************************************************************/
+
+#include <analyses/variable-sensitivity/variable_sensitivity_object_factory.h>
+#include <analyses/variable-sensitivity/variable_sensitivity_test_helpers.h>
+#include <testing-utils/use_catch.h>
+
+#include <util/bitvector_types.h>
+
+static merge_result<const value_set_abstract_objectt>
+widening_merge(abstract_object_pointert op1, abstract_object_pointert op2)
+{
+  auto result = abstract_objectt::merge(op1, op2, widen_modet::could_widen);
+
+  return {result.modified, as_value_set(result.object)};
+}
+
+SCENARIO(
+  "widening merge value_set_abstract_object",
+  "[core][analyses][variable-sensitivity][value_set_abstract_object][merge]")
+{
+  auto type = signedbv_typet(32);
+  auto val0 = from_integer(0, type);
+  auto val1 = from_integer(1, type);
+  auto val2 = from_integer(2, type);
+  auto val3 = from_integer(3, type);
+  auto val4 = from_integer(4, type);
+  auto val5 = from_integer(5, type);
+  auto val6 = from_integer(6, type);
+  auto val7 = from_integer(7, type);
+  auto val8 = from_integer(8, type);
+  auto val9 = from_integer(9, type);
+  auto val10 = from_integer(10, type);
+  auto val11 = from_integer(11, type);
+  auto val12 = from_integer(12, type);
+  auto val13 = from_integer(13, type);
+
+  auto config = vsd_configt::constant_domain();
+  config.context_tracking.data_dependency_context = false;
+  config.context_tracking.last_write_context = false;
+  auto object_factory =
+    variable_sensitivity_object_factoryt::configured_with(config);
+  abstract_environmentt environment{object_factory};
+  environment.make_top();
+  symbol_tablet symbol_table;
+  namespacet ns(symbol_table);
+
+  GIVEN("value_set merges which don't widen")
+  {
+    WHEN("merging {1, 2} with {1, 2}")
+    {
+      auto op1 = make_value_set({val1, val2}, environment, ns);
+      auto op2 = make_value_set({val1, val2}, environment, ns);
+
+      auto merged = widening_merge(op1, op2);
+
+      THEN("result is unmodified {1, 2}")
+      {
+        EXPECT_UNMODIFIED(merged, {val1, val2});
+      }
+    }
+    WHEN("merging {1, 5} with {2, 3}")
+    {
+      auto op1 = make_value_set({val1, val5}, environment, ns);
+      auto op2 = make_value_set({val2, val3}, environment, ns);
+
+      auto merged = widening_merge(op1, op2);
+
+      THEN("result is unmodified {1, 2, 3, 5}")
+      {
+        EXPECT_MODIFIED(merged, {val1, val2, val3, val5});
+      }
+    }
+    WHEN("merging { 1, 4, 7, 10, 13 } with { 2, 3, 5, 6, 8, 9, 11, 12 }")
+    {
+      auto op1 =
+        make_value_set({val1, val4, val7, val10, val13}, environment, ns);
+      auto op2 = make_value_set(
+        {val2, val3, val5, val6, val8, val9, val11, val12}, environment, ns);
+
+      auto merged = widening_merge(op1, op2);
+
+      THEN("result is compacted but not widened { [1, 5], 6, 7, 8, [9, 13]")
+      {
+        auto interval_1_5 = constant_interval_exprt(val1, val5);
+        auto interval_9_13 = constant_interval_exprt(val9, val13);
+        EXPECT_MODIFIED(
+          merged, {interval_1_5, val6, val7, val8, interval_9_13});
+      }
+    }
+  }
+}