MLCE-736 'Adding support for TfLite Models'

* Added constant input supports for Pack/Stack, Concatenation operators
* Added Int32 support to Pack/Stack operator on CpuRef
* Removed unsupported operator from TfLite Delegate

Signed-off-by: Sadik Armagan <sadik.armagan@arm.com>
Change-Id: I64203e174300d23eedeb22bddefe07e931c4eff3

3 files changed, 22 insertions, 32 deletions

diff --git a/delegate/src/Control.hpp b/delegate/src/Control.hpp
index a9645149b4..f20b9f0cc3 100644
--- a/delegate/src/Control.hpp
+++ b/delegate/src/Control.hpp
@@ -72,20 +72,8 @@ TfLiteStatus VisitConcatenationOperator(DelegateData& delegateData,
     for (unsigned int i = 0; i < numInputs; ++i)
     {
         const TfLiteTensor& tfLiteInputTensor = tfLiteTensors[tfLiteNode->inputs->data[i]];
-        if(!IsValid(&tfLiteInputTensor))
+        if (!IsValid(tfLiteContext, tfLiteInputTensor, tfLiteConcatOperatorCode, nodeIndex))
         {
-            TF_LITE_MAYBE_KERNEL_LOG(
-                tfLiteContext,
-                "TfLiteArmnnDelegate: Invalid input tensor in operator #%d node #%d: ",
-                tfLiteConcatOperatorCode, nodeIndex);
-            return kTfLiteError;
-        }
-        if (IsDynamicTensor(tfLiteInputTensor))
-        {
-            TF_LITE_MAYBE_KERNEL_LOG(
-                tfLiteContext,
-                "TfLiteArmnnDelegate: Dynamic input tensors are not supported in operator #%d node #%d: ",
-                tfLiteConcatOperatorCode, nodeIndex);
             return kTfLiteError;
         }
 
@@ -101,20 +89,8 @@ TfLiteStatus VisitConcatenationOperator(DelegateData& delegateData,
                    [](armnn::TensorInfo& t)->const armnn::TensorInfo*{ return &t; });
 
     const TfLiteTensor& tfLiteOutputTensor = tfLiteTensors[tfLiteNode->outputs->data[0]];
-    if(!IsValid(&tfLiteOutputTensor))
+    if (!IsValid(tfLiteContext, tfLiteOutputTensor, tfLiteConcatOperatorCode, nodeIndex))
     {
-        TF_LITE_MAYBE_KERNEL_LOG(
-            tfLiteContext,
-            "TfLiteArmnnDelegate: Invalid output tensor in operator #%d node #%d: ",
-            tfLiteConcatOperatorCode, nodeIndex);
-        return kTfLiteError;
-    }
-    if (IsDynamicTensor(tfLiteOutputTensor))
-    {
-        TF_LITE_MAYBE_KERNEL_LOG(
-            tfLiteContext,
-            "TfLiteArmnnDelegate: Dynamic output tensors are not supported in operator #%d node #%d: ",
-            tfLiteConcatOperatorCode, nodeIndex);
         return kTfLiteError;
     }
 
@@ -165,6 +141,16 @@ TfLiteStatus VisitConcatenationOperator(DelegateData& delegateData,
     armnn::IConnectableLayer* concatenationLayer = delegateData.m_Network->AddConcatLayer(concatDescriptor);
     ARMNN_ASSERT(concatenationLayer != nullptr);
 
+    // Connect the Constant Inputs
+    auto inputsTensorsProcess = ProcessInputs(concatenationLayer,
+                                              delegateData,
+                                              tfLiteContext,
+                                              tfLiteNode);
+    if (inputsTensorsProcess == kTfLiteError)
+    {
+        return inputsTensorsProcess;
+    }
+
     armnn::IOutputSlot& outputSlot = concatenationLayer->GetOutputSlot(0);
     outputSlot.SetTensorInfo(outputTensorInfo);
     Connect(concatenationLayer, tfLiteNode, delegateData);
diff --git a/delegate/src/Pack.hpp b/delegate/src/Pack.hpp
index 59851cd637..5e93ba3f2a 100644
--- a/delegate/src/Pack.hpp
+++ b/delegate/src/Pack.hpp
@@ -99,6 +99,16 @@ TfLiteStatus VisitPackOperator(DelegateData& delegateData,
     armnn::IConnectableLayer* layer = delegateData.m_Network->AddStackLayer(desc);
     ARMNN_ASSERT(layer != nullptr);
 
+    // Connect the Constant Inputs
+    auto inputsTensorsProcess = ProcessInputs(layer,
+                                              delegateData,
+                                              tfLiteContext,
+                                              tfLiteNode);
+    if (inputsTensorsProcess == kTfLiteError)
+    {
+        return inputsTensorsProcess;
+    }
+
     armnn::IOutputSlot& outputSlot = layer->GetOutputSlot(0);
     outputSlot.SetTensorInfo(outputTensorInfo);
 
diff --git a/delegate/src/armnn_delegate.cpp b/delegate/src/armnn_delegate.cpp
index b18d234d69..ed19b72787 100644
--- a/delegate/src/armnn_delegate.cpp
+++ b/delegate/src/armnn_delegate.cpp
@@ -623,12 +623,6 @@ TfLiteStatus ArmnnSubgraph::VisitNode(DelegateData& delegateData,
                                        tfLiteNode,
                                        nodeIndex,
                                        kTfLiteBuiltinGather);
-        case kTfLiteBuiltinGatherNd:
-            return VisitGatherOperator(delegateData,
-                                       tfLiteContext,
-                                       tfLiteNode,
-                                       nodeIndex,
-                                       kTfLiteBuiltinGatherNd);
         case kTfLiteBuiltinGreater:
             return VisitComparisonOperator(delegateData,
                                            tfLiteContext,