IVGCVSW-7450 Fix delegate fallback when fused activation is unsupported

 In layers that support fused activations, we check for activation
 layer support after we already create the base layer. This breaks
 the fallback as we already added the base layer to the graph.

 * Creates ValidateFusedActivation shared function
 * Moves Activation validation higher in the VisitFunction

Signed-off-by: Ryan OShea <ryan.oshea3@arm.com>
Change-Id: I239af360923f695fc374ddeaeefa24c062eaf9e8

1 files changed, 17 insertions, 4 deletions

diff --git a/delegate/src/ElementwiseBinary.hpp b/delegate/src/ElementwiseBinary.hpp
index caf02624be..f21d6afc28 100644
--- a/delegate/src/ElementwiseBinary.hpp
+++ b/delegate/src/ElementwiseBinary.hpp
@@ -1,5 +1,5 @@
 //
-// Copyright © 2022 Arm Ltd and Contributors. All rights reserved.
+// Copyright © 2022-2023 Arm Ltd and Contributors. All rights reserved.
 // SPDX-License-Identifier: MIT
 //
 
@@ -254,6 +254,21 @@ TfLiteStatus VisitElementwiseBinaryOperator(DelegateData& delegateData,
 
     const armnn::TensorInfo& outputTensorInfo = GetTensorInfoForTfLiteTensor(tfLiteOutputTensor, true);
 
+    auto* tfLiteNodeParameters = reinterpret_cast<TfLiteAddParams*>(tfLiteNode->builtin_data);
+    TfLiteFusedActivation activationType;
+    if (tfLiteNodeParameters)
+    {
+        activationType = tfLiteNodeParameters->activation;
+
+        const armnn::TensorInfo& activationOutputInfo = GetTensorInfoForTfLiteTensor(tfLiteOutputTensor, true);
+        TfLiteStatus activationStatus = ValidateFusedActivationOperator(delegateData, tfLiteContext, outputTensorInfo,
+                                                                        outputTensorInfo, activationType);
+        if(activationStatus != kTfLiteOk)
+        {
+            return kTfLiteError;
+        }
+    }
+
     if (!delegateData.m_Network)
     {
         switch(elementwiseBinaryOperatorCode)
@@ -361,14 +376,12 @@ TfLiteStatus VisitElementwiseBinaryOperator(DelegateData& delegateData,
         return kTfLiteError;
     }
 
-    auto* tfLiteNodeParameters = reinterpret_cast<TfLiteAddParams*>(tfLiteNode->builtin_data);
     if (!tfLiteNodeParameters)
     {
         // No Activation
         return kTfLiteOk;
     }
-    // Check activation
-    TfLiteFusedActivation activationType = tfLiteNodeParameters->activation;
+    // Check and Create Activation
     return FusedActivation(tfLiteContext, tfLiteNode, activationType, elementwiseBinaryLayer, 0, delegateData);
 }