COMPMID-2753: Add support for QASYMM8_SIGNED in CL kernels/functions

Change-Id: I7ed2d43f33458ba0571323f6fa9dc2e45fcd672a
Signed-off-by: Manuel Bottini <manuel.bottini@arm.com>
Reviewed-on: https://review.mlplatform.org/c/2516
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Michele Di Giorgio <michele.digiorgio@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>
diff --git a/tests/validation/reference/Scale.cpp b/tests/validation/reference/Scale.cpp
index 4e5189e..f382ee3 100644
--- a/tests/validation/reference/Scale.cpp
+++ b/tests/validation/reference/Scale.cpp
@@ -210,6 +210,25 @@
     return dst;
 }
 
+template <>
+SimpleTensor<int8_t> scale(const SimpleTensor<int8_t> &src, float scale_x, float scale_y, InterpolationPolicy policy, BorderMode border_mode, int8_t constant_border_value,
+                           SamplingPolicy sampling_policy, bool ceil_policy_scale)
+{
+    SimpleTensor<int8_t> dst;
+    if(src.quantization_info().uniform().scale != 0.f)
+    {
+        SimpleTensor<float> src_tmp                 = convert_from_asymmetric(src);
+        float               constant_border_value_f = dequantize_qasymm8_signed(constant_border_value, src.quantization_info());
+        SimpleTensor<float> dst_tmp                 = scale_core<float>(src_tmp, scale_x, scale_y, policy, border_mode, constant_border_value_f, sampling_policy, ceil_policy_scale);
+        dst                                         = convert_to_asymmetric<int8_t>(dst_tmp, src.quantization_info());
+    }
+    else
+    {
+        dst = scale_core<int8_t>(src, scale_x, scale_y, policy, border_mode, constant_border_value, sampling_policy, ceil_policy_scale);
+    }
+    return dst;
+}
+
 template SimpleTensor<int16_t> scale(const SimpleTensor<int16_t> &src, float scale_x, float scale_y, InterpolationPolicy policy, BorderMode border_mode, int16_t constant_border_value,
                                      SamplingPolicy sampling_policy, bool ceil_policy_scale, bool align_corners);
 template SimpleTensor<half> scale(const SimpleTensor<half> &src, float scale_x, float scale_y, InterpolationPolicy policy, BorderMode border_mode, half constant_border_value,