[TFLite FE][TF FE] Mark dequantization before TSGeneral

src/frontends/tensorflow/src/frontend.cpp

@@ -33,6 +33,7 @@
 #include "transformations/common_optimizations/reverse_shape_and_type_infer.hpp"
 #include "transformations/control_flow/unroll_if.hpp"
 #include "transformations/fp16_compression/mark_decompression_convert_constant_folding.hpp"
+#include "transformations/low_precision/mark_dequantization_subgraph.hpp"
 #include "transformations/resolve_names_collisions.hpp"
 #include "transformations/switch_merge_resolve.hpp"
 #include "transformations/transpose_sinking/ts_general.hpp"
@@ -426,6 +427,9 @@ void FrontEnd::normalize(const std::shared_ptr<ov::Model>& model) const {
 
     manager.register_pass<ov::pass::UnrollIf>();
     manager.register_pass<ov::pass::RemoveConcatZeroDimInput>();
+    // TSGeneral runs ConstantFolding; mark dequantization before it.
+    manager.register_pass<ov::pass::MarkDequantization>(
+        ov::element::TypeVector{ov::element::i8, ov::element::u8, ov::element::i4, ov::element::u4});
     manager.register_pass<ov::pass::TransposeSinkingGeneral>();
     manager.register_pass<ov::pass::ReverseShapeAndTypeInfer>();
     manager.register_pass<ov::pass::ResolveNameCollisions>(true);

src/frontends/tensorflow_lite/src/frontend.cpp

@@ -18,6 +18,7 @@
 #include "tflite_transformations/tflite_quantize_resolver.hpp"
 #include "transformations/common_optimizations/transpose_sinking.hpp"
 #include "transformations/fp16_compression/mark_decompression_convert_constant_folding.hpp"
+#include "transformations/low_precision/mark_dequantization_subgraph.hpp"
 #include "transformations/resolve_names_collisions.hpp"
 #include "transformations/transpose_sinking/ts_general.hpp"
 
@@ -276,6 +277,9 @@ void FrontEnd::normalize(const std::shared_ptr<ov::Model>& function) const {
     manager.register_pass<ov::pass::MarkCompressedFloatConstants>();
     manager.register_pass<ov::frontend::tensorflow_lite::pass::TFLQuantizeResolver>();
     manager.register_pass<ov::frontend::tensorflow_lite::pass::Rfft2dSimplifier>();
+    // TSGeneral runs ConstantFolding; mark dequantization before it.
+    manager.register_pass<ov::pass::MarkDequantization>(
+        ov::element::TypeVector{ov::element::i8, ov::element::u8, ov::element::i4, ov::element::u4});
     manager.register_pass<ov::pass::TransposeSinking>();
     manager.register_pass<ov::pass::TransposeSinkingGeneral>();
     manager.register_pass<ov::pass::ResolveNameCollisions>(true);

src/frontends/tensorflow_lite/tests/quantization.cpp

@@ -10,6 +10,8 @@
 #include "common_test_utils/type_prop.hpp"
 #include "conversion_extension.hpp"
 #include "gtest/gtest.h"
+#include "openvino/op/convert.hpp"
+#include "openvino/pass/constant_folding.hpp"
 #include "tf_utils.hpp"
 
 using namespace ov;
@@ -94,3 +96,15 @@ OPENVINO_TEST(TensorFlowLiteTrickyModels, tflite_quantize_dequantize_uint8) {
                                          {-4.f, -4.f, -4.f, 0.f, 0.f, 0.5f, 0.75f, 1.f, 1.25f, 1.25f, 59.75f, 59.75f});
     test_case.run_with_tolerance_as_fp(0.001f);
 }
+
+OPENVINO_TEST(TensorFlowLiteTrickyModels, tflite_qdq_convert_is_marked_disable_cf) {
+    auto model = convert_model("qdq_uint8.tflite");
+    bool has_cf_disabled_convert = false;
+    for (const auto& op : model->get_ordered_ops()) {
+        if (ov::is_type<ov::op::v0::Convert>(op) && ov::pass::constant_folding_is_disabled(op)) {
+            has_cf_disabled_convert = true;
+            break;
+        }
+    }
+    EXPECT_TRUE(has_cf_disabled_convert);
+}