[TFLite] Support quantized GREATER op in TFLite frontend

Support GREATER quantization operation conversion as part of issue apache#9187
Continuation of apache#11519

python/tvm/relay/frontend/tflite.py

@@ -1291,7 +1291,13 @@ def convert_square(self, op):
 
         return out
 
-    def _convert_elemwise(self, relay_op, op, ignore_qnn_params=False):
+    def _convert_elemwise(
+        self,
+        relay_op,
+        op,
+        ignore_qnn_params=False,
+        comparison_op=False,
+    ):
         """Generic method to Convert TFLite elemwise"""
         try:
             from tflite.AddOptions import AddOptions
@@ -1316,7 +1322,7 @@ def _convert_elemwise(self, relay_op, op, ignore_qnn_params=False):
 
         # TFLite format demands equal scale and zero_point tuple parameters for some operations
         # to allow us to use non-quantized operation instead of quantized if ignore_qnn_params=True
-        if ignore_qnn_params:
+        if ignore_qnn_params and not comparison_op:
             assert (
                 lhs_tensor.qnn_params
                 and self.has_same_qnn_params(lhs_tensor, output_tensor)
@@ -1431,12 +1437,7 @@ def convert_minimum(self, op):
 
     def convert_greater(self, op):
         """Convert TFLite GREATER"""
-        # Check if the input tensor is quantized, call QNN op
-        if self.is_quantized(op):
-            raise tvm.error.OpNotImplemented(
-                "TFlite quantized GREATER operator is not supported yet."
-            )
-        return self._convert_elemwise(_op.greater, op)
+        return self._convert_elemwise(_op.greater, op, self.is_quantized(op), comparison_op=True)
 
     def convert_squared_difference(self, op):
         """Convert TFLite SQUARED DIFFERENCE"""
@@ -1475,7 +1476,7 @@ def convert_less_equal(self, op):
 
     def convert_equal(self, op):
         """Convert TFLite EQUAL"""
-        return self._convert_elemwise(_op.equal, op, self.is_quantized(op))
+        return self._convert_elemwise(_op.equal, op, self.is_quantized(op), comparison_op=True)
 
     def convert_not_equal(self, op):
         """Convert TFLite NOT_EQUAL"""

tests/python/frontend/tflite/test_forward.py

@@ -2254,6 +2254,7 @@ def _test_elemwise(
     quantized=False,
     qnn_op=None,
     same_qnn_params=False,
+    comparison_op=False,
 ):
     """One iteration of elemwise"""
 
@@ -2298,7 +2299,7 @@ def __test_elemwise(in_data):
                 if x[0] is not None
             }
 
-            if math_op is math_ops.equal:
+            if comparison_op:
                 out = math_op(inq_data[0], inq_data[1])
                 out = with_fused_activation_function(out, fused_activation_function)
 
@@ -2307,13 +2308,17 @@ def __test_elemwise(in_data):
                     [x + ":0" for x in input_range.keys()],
                     [x[1] for x in zip(in_data, inq_data) if x[0] is not None],
                     [out],
+                    quantized=True,
+                    input_range=input_range,
+                    experimental_new_converter=same_qnn_params,
                 )
             else:
                 out = math_op(inq_data[0], inq_data[1])
                 out = with_fused_activation_function(out, fused_activation_function)
                 out = tf.quantization.fake_quant_with_min_max_args(
                     out, min=out_min, max=out_max, name="out"
                 )
+
                 # Note same_qnn_params uses experimental_new_converter as toco failed
                 compare_tflite_with_tvm(
                     [x[1] for x in zip(in_data, data) if x[0] is not None],
@@ -2440,9 +2445,17 @@ def _test_minimum(data, fused_activation_function=None, quantized=False, qnn_op=
 # -------
 
 
-def _test_greater(data):
+def _test_greater(data, fused_activation_function=None, quantized=False, qnn_op=None):
     """One iteration of greater"""
-    return _test_elemwise(math_ops.greater, data)
+    return _test_elemwise(
+        math_ops.greater,
+        data,
+        fused_activation_function,
+        quantized,
+        qnn_op,
+        same_qnn_params=True,
+        comparison_op=True,
+    )
 
 
 #######################################################################
@@ -2489,6 +2502,7 @@ def _test_equal(data, fused_activation_function=None, quantized=False, qnn_op=No
         quantized,
         qnn_op,
         same_qnn_params=True,
+        comparison_op=True,
     )
 
 
@@ -2615,6 +2629,7 @@ def test_all_elemwise():
     _test_forward_elemwise(_test_minimum)
     _test_forward_elemwise_quantized(_test_minimum)
     _test_forward_elemwise(_test_greater)
+    _test_forward_elemwise_quantized(_test_greater)
     _test_forward_elemwise(_test_squared_difference)
     _test_forward_elemwise(_test_greater_equal)
     _test_forward_elemwise(_test_less)