[ONNX] ArgMin/ArgMax support for select_last_index

ngraph/frontend/onnx_import/src/op/argmax.cpp

@@ -26,13 +26,6 @@ namespace ngraph
             {
                 OutputVector argmax(const Node& node)
                 {
-                    const auto select_last_index =
-                        node.get_attribute_value<std::int64_t>("select_last_index", 0);
-                    CHECK_VALID_NODE(node,
-                                     select_last_index == 0,
-                                     "Mode 'select_last_index=1' is not supported by current "
-                                     "implementation of ArgMax");
-
                     const utils::ArgMinMaxFactory arg_factory(node);
                     return {arg_factory.make_arg_max()};
                 }

ngraph/frontend/onnx_import/src/op/argmin.cpp

@@ -26,13 +26,6 @@ namespace ngraph
             {
                 OutputVector argmin(const Node& node)
                 {
-                    const auto select_last_index =
-                        node.get_attribute_value<std::int64_t>("select_last_index", 0);
-                    CHECK_VALID_NODE(node,
-                                     select_last_index == 0,
-                                     "Mode 'select_last_index=1' is not supported by current "
-                                     "implementation of ArgMin");
-
                     const utils::ArgMinMaxFactory arg_factory(node);
                     return {arg_factory.make_arg_min()};
                 }

ngraph/frontend/onnx_import/src/utils/arg_min_max_factory.cpp

@@ -4,6 +4,7 @@
 
 #include "utils/arg_min_max_factory.hpp"
 #include "default_opset.hpp"
+#include "ngraph/opsets/opset1.hpp"
 #include "ngraph/validation_util.hpp"
 
 namespace ngraph
@@ -14,9 +15,11 @@ namespace ngraph
         {
             ArgMinMaxFactory::ArgMinMaxFactory(const Node& node)
                 : m_keep_dims{node.get_attribute_value<std::int64_t>("keepdims", 1)}
+                , m_input_node{node.get_ng_inputs().at(0)}
                 , m_axis{node.get_attribute_value<std::int64_t>("axis", 0)}
+                , m_select_last_index{
+                      node.get_attribute_value<std::int64_t>("select_last_index", 0)}
             {
-                m_input_node = node.get_ng_inputs().at(0);
             }
 
             std::shared_ptr<ngraph::Node> ArgMinMaxFactory::make_arg_max() const
@@ -34,19 +37,80 @@ namespace ngraph
             {
                 const auto k_node =
                     default_opset::Constant::create(ngraph::element::i64, Shape{}, {1});
+
+                if (m_select_last_index == 1)
+                {
+                    // Example (ArgMin):
+                    // The goal is to get the index of the last occurence of the
+                    // minimum value present in given input tensor.
+                    //
+                    // Input:           [1, 2, 1, 3, 4, 4]
+                    // Expected output: [2]
+                    //
+                    // Top-K is always returning the "most-left" result. The trick is to
+                    // reverse input to find the "most-right" occurence which is equal to
+                    // the last occurence in the original input.
+                    // reverse = [4, 4, 3, 1, 2, 1]
+                    //
+                    // Run TopK on reversed tensor, in the example output with index values
+                    // is equal to:
+                    // topk->output(1) = 3
+                    //
+                    // Using ShapeOf and Gather on input obtain length of the input tensor
+                    // along axis, in the example this is equal to:
+                    // dims_on_axis = 6
+                    //
+                    // Now using two Substract ops calculate resulting index:
+                    // res_index = dims_on_axis - topk->output(1) = 6 - 3 = 3
+                    // result = res_index - 1 = 3 - 1 = 2
+
+                    const auto axis_node =
+                        default_opset::Constant::create(ngraph::element::i64, Shape{1}, {m_axis});
+                    const auto reverse = std::make_shared<opset1::Reverse>(
+                        m_input_node, axis_node, opset1::Reverse::Mode::INDEX);
+
+                    const auto topk = std::make_shared<default_opset::TopK>(
+                        reverse, k_node, m_axis, mode, default_opset::TopK::SortType::NONE);
+
+                    const auto data_shape = std::make_shared<default_opset::ShapeOf>(m_input_node);
+                    const auto dims_on_axis = std::make_shared<default_opset::Gather>(
+                        data_shape,
+                        axis_node,
+                        default_opset::Constant::create(ngraph::element::i64, Shape{}, {0}));
+
+                    const auto res_index = std::make_shared<default_opset::Subtract>(
+                        dims_on_axis,
+                        std::make_shared<default_opset::Convert>(topk->output(1), element::i64));
+                    const auto result = std::make_shared<default_opset::Subtract>(
+                        res_index,
+                        default_opset::Constant::create(ngraph::element::i64, Shape{1}, {1}));
+
+                    if (m_keep_dims == 0)
+                    {
+                        const auto axis_to_remove = default_opset::Constant::create(
+                            element::u64, Shape{}, {topk->get_axis()});
+
+                        return std::make_shared<default_opset::Squeeze>(result, axis_to_remove);
+                    }
+
+                    return result;
+                }
+
                 const auto topk = std::make_shared<default_opset::TopK>(
                     m_input_node, k_node, m_axis, mode, default_opset::TopK::SortType::NONE);
 
+                const auto result =
+                    std::make_shared<default_opset::Convert>(topk->output(1), element::i64);
+
                 if (m_keep_dims == 0)
                 {
                     const auto axis_to_remove =
                         default_opset::Constant::create(element::u64, Shape{}, {topk->get_axis()});
-                    const auto reshaped_indices =
-                        std::make_shared<default_opset::Squeeze>(topk->output(1), axis_to_remove);
 
-                    return std::make_shared<default_opset::Convert>(reshaped_indices, element::i64);
+                    return std::make_shared<default_opset::Squeeze>(result, axis_to_remove);
                 }
-                return std::make_shared<default_opset::Convert>(topk->output(1), element::i64);
+
+                return result;
             }
         } // namespace utils
     }     // namespace onnx_import

ngraph/frontend/onnx_import/src/utils/arg_min_max_factory.hpp

@@ -39,6 +39,7 @@ namespace ngraph
                 const std::int64_t m_keep_dims;
                 Output<ngraph::Node> m_input_node;
                 std::int64_t m_axis;
+                std::int64_t m_select_last_index;
             };
 
         } // namespace utils

ngraph/python/tests/__init__.py

@@ -113,12 +113,12 @@ def xfail_test(reason="Mark the test as expected to fail", strict=True):
 xfail_issue_44976 = xfail_test(reason="E   RuntimeError: Quantize layer with name:"
                                       "FakeQuantize_xxx has non const input on 1 port")
 xfail_issue_46762 = xfail_test(reason="Incorrect result of Minimum op if uint data type is used")
-xfail_issue_46765 = xfail_test(reason="select_last_index attribute is not supported by ArgMin and ArgMax")
 xfail_issue_47323 = xfail_test(reason="RuntimeError: The plugin does not support FP64")
 xfail_issue_47337 = xfail_test(reason="RuntimeError: Unsupported dynamic ops: v1::OneHot")
 xfail_issue_33593 = xfail_test(reason="Current implementation of MaxPool doesn't support indices output")
 xfail_issue_51993 = xfail_test(reason="PRelu supports only 1D tensor for 'slope' input broadcasted"
                                       "by channel")
+xfail_issue_55760 = xfail_test(reason="RuntimeError: Reversed axis have axes above the source space shape")
 
 # Model MSFT issues:
 xfail_issue_37957 = xfail_test(reason="RuntimeError: nGraph does not support the following ONNX operations:"

ngraph/python/tests/test_onnx/test_backend.py

@@ -50,7 +50,6 @@
                    xfail_issue_45180,
                    xfail_issue_45344,
                    xfail_issue_46762,
-                   xfail_issue_46765,
                    xfail_issue_47323,
                    xfail_issue_47337,
                    xfail_issue_48052,
@@ -60,7 +59,8 @@
                    xfail_issue_49753,
                    xfail_issue_49754,
                    xfail_issue_52463,
-                   xfail_issue_51993)
+                   xfail_issue_51993,
+                   xfail_issue_55760)
 
 
 def expect_fail(test_case_path, xfail):  # type: (str) -> None
@@ -165,23 +165,11 @@ def expect_fail(test_case_path, xfail):  # type: (str) -> None
      "OnnxBackendNodeModelTest.test_min_uint16_cpu",
      "OnnxBackendNodeModelTest.test_min_uint32_cpu",
      "OnnxBackendNodeModelTest.test_min_uint64_cpu"),
-    (xfail_issue_46765,
+    (xfail_issue_55760,
      "OnnxBackendNodeModelTest.test_argmax_negative_axis_keepdims_example_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmax_keepdims_example_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmax_no_keepdims_example_select_last_index_cpu",
      "OnnxBackendNodeModelTest.test_argmin_negative_axis_keepdims_example_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmin_keepdims_example_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmin_no_keepdims_example_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmax_default_axis_example_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmax_default_axis_random_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmax_keepdims_random_select_last_index_cpu",
      "OnnxBackendNodeModelTest.test_argmax_negative_axis_keepdims_random_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmax_no_keepdims_random_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmin_default_axis_example_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmin_default_axis_random_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmin_keepdims_random_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmin_negative_axis_keepdims_random_select_last_index_cpu",
-     "OnnxBackendNodeModelTest.test_argmin_no_keepdims_random_select_last_index_cpu"),
+     "OnnxBackendNodeModelTest.test_argmin_negative_axis_keepdims_random_select_last_index_cpu"),
     (xfail_issue_38091,
      "OnnxBackendNodeModelTest.test_gather_negative_indices_cpu"),
     (xfail_issue_52463,

ngraph/test/models/onnx/argmax_select_last_index.prototxt

@@ -50,6 +50,9 @@ graph {
           dim {
             dim_value: 3
           }
+          dim {
+            dim_value: 1
+          }
         }
       }
     }

ngraph/test/onnx/onnx_import.in.cpp

@@ -2503,45 +2503,24 @@ NGRAPH_TEST(${BACKEND_NAME}, onnx_model_argmin_float)
 
 NGRAPH_TEST(${BACKEND_NAME}, onnx_model_argmax_select_last_index)
 {
-    try
-    {
-        auto function = onnx_import::import_onnx_model(
-            file_util::path_join(SERIALIZED_ZOO, "onnx/argmax_select_last_index.prototxt"));
-        FAIL() << "Expected exception was not thrown";
-    }
-    catch (const ngraph::ngraph_error& e)
-    {
-        EXPECT_HAS_SUBSTRING(
-            e.what(),
-            std::string(
-                "Mode 'select_last_index=1' is not supported by current implementation of ArgMax"));
-    }
-    catch (...)
-    {
-        FAIL() << "Expected OnnxNodeValidationFailure exception was not thrown";
-    }
+    auto function = onnx_import::import_onnx_model(
+        file_util::path_join(SERIALIZED_ZOO, "onnx/argmax_select_last_index.prototxt"));
+
+    auto test_case = test::TestCase<TestEngine>(function);
+    test_case.add_input<float>(Shape{4, 3}, {1, 1, 1, 0.5, 3, 4, 0.5, 1, 1.1, 0, 3, 0});
+    test_case.add_expected_output<std::int64_t>(Shape{1, 3}, {0, 3, 1});
+    test_case.run();
 }
 
 NGRAPH_TEST(${BACKEND_NAME}, onnx_model_argmin_select_last_index)
 {
-    try
-    {
-        auto function = onnx_import::import_onnx_model(
-            file_util::path_join(SERIALIZED_ZOO, "onnx/argmin_select_last_index.prototxt"));
-        FAIL() << "Expected exception was not thrown";
-    }
-    catch (const ngraph::ngraph_error& e)
-    {
-        EXPECT_HAS_SUBSTRING(
-            e.what(),
-            std::string(
-                "Mode 'select_last_index=1' is not supported by current implementation of ArgMin"));
-        std::string what{e.what()};
-    }
-    catch (...)
-    {
-        FAIL() << "Expected OnnxNodeValidationFailure exception was not thrown";
-    }
+    auto function = onnx_import::import_onnx_model(
+        file_util::path_join(SERIALIZED_ZOO, "onnx/argmin_select_last_index.prototxt"));
+
+    auto test_case = test::TestCase<TestEngine>(function);
+    test_case.add_input<float>(Shape{4, 3}, {1, 1, 1, 2, 3, 4, 2, 1, 1.1, 3, 3, 8});
+    test_case.add_expected_output<std::int64_t>(Shape{4}, {2, 0, 1, 1});
+    test_case.run();
 }
 
 NGRAPH_TEST(${BACKEND_NAME}, onnx_model_top_k)

ngraph/test/runtime/ie/unit_test.manifest

@@ -131,6 +131,8 @@ arg_max_dyn_shape
 # Result mismatch
 onnx_model_argmax_float
 onnx_model_argmin_float
+onnx_model_argmax_select_last_index
+onnx_model_argmin_select_last_index
 
 # Constant has zero dimension that is not allowable
 onnx_dyn_shapes_transpose