Add QASYMM8_SIGNED support to graph examples via graph mutator

Related to COMPMID-4279

Signed-off-by: SiCongLi <sicong.li@arm.com>
Change-Id: I6c737536b4e614cc9975003acca766803f55bf0b
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/5206
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
diff --git a/src/graph/Utils.cpp b/src/graph/Utils.cpp
index 2835af3..8e12689 100644
--- a/src/graph/Utils.cpp
+++ b/src/graph/Utils.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018-2020 Arm Limited.
+ * Copyright (c) 2018-2021 Arm Limited.
  *
  * SPDX-License-Identifier: MIT
  *
@@ -81,9 +81,22 @@
     const bool is_target_gc = target == Target::GC;
 
     // Passes that mutate graph IR
-    if(cfg.convert_to_uint8)
+    if(cfg.use_synthetic_type)
     {
-        pm.append(std::make_unique<SyntheticDataTypeMutator>(), !is_target_gc);
+        switch(cfg.synthetic_type)
+        {
+            case DataType::QASYMM8:
+            case DataType::QASYMM8_SIGNED:
+            {
+                pm.append(std::make_unique<SyntheticDataTypeMutator>(cfg.synthetic_type), !is_target_gc);
+                break;
+            }
+            default:
+            {
+                ARM_COMPUTE_ERROR("Unsupported DataType for SyntheticDataTypeMutator");
+                break;
+            }
+        }
     }
     pm.append(std::make_unique<NodeFusionMutator>(), !is_target_gc);
     pm.append(std::make_unique<GroupedConvolutionMutator>());