Support add operation on mixed tensors.

2 files changed, 74 insertions, 2 deletions

diff --git a/eval/src/tests/tensor/tensor_add_operation/tensor_add_operation_test.cpp b/eval/src/tests/tensor/tensor_add_operation/tensor_add_operation_test.cpp
index 2f36aba6e3a..4c92dc717a7 100644
--- a/eval/src/tests/tensor/tensor_add_operation/tensor_add_operation_test.cpp
+++ b/eval/src/tests/tensor/tensor_add_operation/tensor_add_operation_test.cpp
@@ -21,6 +21,15 @@ assertAdd(const TensorSpec &source, const TensorSpec &arg, const TensorSpec &exp
     EXPECT_EQ(actual, expected);
 }
 
+void
+assertNullTensor(const TensorSpec &source, const TensorSpec &arg)
+{
+    auto sourceTensor = makeTensor<Tensor>(source);
+    auto argTensor = makeTensor<Tensor>(arg);
+    auto resultTensor = sourceTensor->add(*argTensor);
+    EXPECT_FALSE(resultTensor);
+}
+
 TEST(TensorAddTest, cells_can_be_added_to_a_sparse_tensor)
 {
     assertAdd(TensorSpec("tensor(x{},y{})")
@@ -35,4 +44,42 @@ TEST(TensorAddTest, cells_can_be_added_to_a_sparse_tensor)
                       .add({{"x","e"},{"y","f"}}, 7));
 }
 
+TEST(TensorAddTest, cells_can_be_added_to_a_mixed_tensor)
+{
+    assertAdd(TensorSpec("tensor(x{},y[2])")
+                      .add({{"x","a"},{"y",0}}, 2)
+                      .add({{"x","a"},{"y",1}}, 3)
+                      .add({{"x","b"},{"y",0}}, 4)
+                      .add({{"x","b"},{"y",1}}, 5),
+              TensorSpec("tensor(x{},y[2])")
+                      .add({{"x","b"},{"y",0}}, 6)
+                      .add({{"x","b"},{"y",1}}, 7)
+                      .add({{"x","c"},{"y",0}}, 8)
+                      .add({{"x","c"},{"y",1}}, 9),
+              TensorSpec("tensor(x{},y[2])")
+                      .add({{"x","a"},{"y",0}}, 2)
+                      .add({{"x","a"},{"y",1}}, 3)
+                      .add({{"x","b"},{"y",0}}, 6)
+                      .add({{"x","b"},{"y",1}}, 7)
+                      .add({{"x","c"},{"y",0}}, 8)
+                      .add({{"x","c"},{"y",1}}, 9));
+}
+
+TEST(TensorAddTest, cells_can_be_added_to_empty_mixed_tensor)
+{
+    assertAdd(TensorSpec("tensor(x{},y[2])"),
+              TensorSpec("tensor(x{},y[2])")
+                      .add({{"x","b"},{"y",0}}, 6)
+                      .add({{"x","b"},{"y",1}}, 7),
+              TensorSpec("tensor(x{},y[2])")
+                      .add({{"x","b"},{"y",0}}, 6)
+                      .add({{"x","b"},{"y",1}}, 7));
+}
+
+TEST(TensorAddTest, tensors_of_different_types_cannot_be_added_together)
+{
+    assertNullTensor(TensorSpec("tensor(x{},y[2])"), TensorSpec("tensor(x{},y{})"));
+    assertNullTensor(TensorSpec("tensor(x{},y[2])"), TensorSpec("tensor(x{},y[3])"));
+}
+
 GTEST_MAIN_RUN_ALL_TESTS
diff --git a/eval/src/vespa/eval/tensor/wrapped_simple_tensor.cpp b/eval/src/vespa/eval/tensor/wrapped_simple_tensor.cpp
index 9df59a63873..1268d6fa9cb 100644
--- a/eval/src/vespa/eval/tensor/wrapped_simple_tensor.cpp
+++ b/eval/src/vespa/eval/tensor/wrapped_simple_tensor.cpp
@@ -12,6 +12,9 @@ LOG_SETUP(".eval.tensor.wrapped_simple_tensor");
 
 namespace vespalib::tensor {
 
+using eval::SimpleTensor;
+using eval::TensorSpec;
+
 bool
 WrappedSimpleTensor::equals(const Tensor &arg) const
 {
@@ -84,9 +87,31 @@ WrappedSimpleTensor::modify(join_fun_t, const CellValues &) const
 }
 
 std::unique_ptr<Tensor>
-WrappedSimpleTensor::add(const Tensor &) const
+WrappedSimpleTensor::add(const Tensor &arg) const
 {
-    LOG_ABORT("should not be reached");
+    const auto *rhs = dynamic_cast<const WrappedSimpleTensor *>(&arg);
+    if (!rhs || type() != rhs->type()) {
+        return Tensor::UP();
+    }
+
+    TensorSpec oldTensor = toSpec();
+    TensorSpec argTensor = rhs->toSpec();
+    TensorSpec result(type().to_spec());
+    for (const auto &cell : oldTensor.cells()) {
+        auto argItr = argTensor.cells().find(cell.first);
+        if (argItr != argTensor.cells().end()) {
+            result.add(argItr->first, argItr->second);
+        } else {
+            result.add(cell.first, cell.second);
+        }
+    }
+    for (const auto &cell : argTensor.cells()) {
+        auto resultItr = result.cells().find(cell.first);
+        if (resultItr == result.cells().end()) {
+            result.add(cell.first, cell.second);
+        }
+    }
+    return std::make_unique<WrappedSimpleTensor>(SimpleTensor::create(result));
 }
 
 std::unique_ptr<Tensor>