[Relay][Frontend][TFlite] Add add parser support for relational ops (#4695)

Add support for: greater_equal, less, less_equal, equal, not_equal
Add tests for the elemwise relational ops

python/tvm/relay/frontend/tflite.py

@@ -89,6 +89,11 @@ class OperatorConverter(object):
             'MAXIMUM': self.convert_maximum,
             'MINIMUM': self.convert_minimum,
             'GREATER': self.convert_greater,
+            'GREATER_EQUAL': self.convert_greater_equal,
+            'LESS': self.convert_less,
+            'LESS_EQUAL': self.convert_less_equal,
+            'EQUAL': self.convert_equal,
+            'NOT_EQUAL': self.convert_not_equal,
             'ZEROS_LIKE': self.convert_zeros_like,
             'REDUCE_MIN': self._convert_reduce_min,
             'REDUCE_MAX': self._convert_reduce_max,
@@ -690,7 +695,7 @@ class OperatorConverter(object):
         # Check if the input tensor is quantized, call QNN op
         if self.is_quantized(op):
             raise tvm.error.OpNotImplemented(
-                'TFlite quantized sub operator is not supported yet.')
+                'TFlite quantized SUB operator is not supported yet.')
         return self._convert_elemwise(_op.subtract, op)
 
     def convert_mul(self, op):
@@ -705,38 +710,43 @@ class OperatorConverter(object):
         # Check if the input tensor is quantized, call QNN op
         if self.is_quantized(op):
             raise tvm.error.OpNotImplemented(
-                'TFlite quantized div operator is not supported yet.')
+                'TFlite quantized DIV operator is not supported yet.')
         return self._convert_elemwise(_op.divide, op)
 
     def convert_pow(self, op):
+        """Convert TFLite POW"""
         # Check if the input tensor is quantized, call QNN op
         if self.is_quantized(op):
             raise tvm.error.OpNotImplemented(
-                'TFlite quantized pow operator is not supported yet.')
+                'TFlite quantized POW operator is not supported yet.')
         return self._convert_elemwise(_op.power, op)
 
     def convert_maximum(self, op):
+        """Convert TFLite MAXIMUM"""
         # Check if the input tensor is quantized, call QNN op
         if self.is_quantized(op):
             raise tvm.error.OpNotImplemented(
-                'TFlite quantized maximum operator is not supported yet.')
+                'TFlite quantized MAXIMUM operator is not supported yet.')
         return self._convert_elemwise(_op.maximum, op)
 
     def convert_minimum(self, op):
+        """Convert TFLite MINIMUM"""
         # Check if the input tensor is quantized, call QNN op
         if self.is_quantized(op):
             raise tvm.error.OpNotImplemented(
-                'TFlite quantized minimum operator is not supported yet.')
+                'TFlite quantized MINIMUM operator is not supported yet.')
         return self._convert_elemwise(_op.minimum, 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.')
+                'TFlite quantized GREATER operator is not supported yet.')
         return self._convert_elemwise(_op.greater, op)
 
     def convert_squared_difference(self, op):
+        """Convert TFLite SQUARED DIFFERENCE"""
         # Check if the input tensor is quantized, call QNN op
         if self.is_quantized(op):
             raise tvm.error.OpNotImplemented(
@@ -747,6 +757,41 @@ class OperatorConverter(object):
         out = _op.power(difference, relay.const(2, exp_type))
         return out
 
+    def convert_greater_equal(self, op):
+        """Convert TFLite GREATER_EQUAL"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized GREATER_EQUAL operator is not supported yet.')
+        return self._convert_elemwise(_op.greater_equal, op)
+
+    def convert_less(self, op):
+        """Convert TFLite LESS"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized LESS operator is not supported yet.')
+        return self._convert_elemwise(_op.less, op)
+
+    def convert_less_equal(self, op):
+        """Convert TFLite LESS_EQUAL"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized LESS_EQUAL operator is not supported yet.')
+        return self._convert_elemwise(_op.less_equal, op)
+
+    def convert_equal(self, op):
+        """Convert TFLite EQUAL"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized EQUAL operator is not supported yet.')
+        return self._convert_elemwise(_op.equal, op)
+
+    def convert_not_equal(self, op):
+        """Convert TFLite NOT_EQUAL"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized NOT_EQUAL operator is not supported yet.')
+        return self._convert_elemwise(_op.not_equal, op)
+
     def convert_zeros_like(self, op):
         """Convert TFLite ZEROS LIKE"""
         try:

tests/python/frontend/tflite/test_forward.py

@@ -863,7 +863,41 @@ def _test_minimum(data):
 def _test_greater(data):
     """ One iteration of greater """
     return _test_elemwise(math_ops.greater, data)
+#######################################################################
+# Greater_equal
+# -------------
+
+def _test_greater_equal(data):
+    """ One iteration of greater_equal """
+    return _test_elemwise(math_ops.greater_equal, data)
+#######################################################################
+# Less
+# ----
+
+def _test_less(data):
+    """ One iteration of less """
+    return _test_elemwise(math_ops.less, data)
+#######################################################################
+# Less_equal
+# ----------
+
+def _test_less_equal(data):
+    """ One iteration of less_equal """
+    return _test_elemwise(math_ops.less_equal, data)
+#######################################################################
+# Equal
+# -----
+
+def _test_equal(data):
+    """ One iteration of equal """
+    return _test_elemwise(math_ops.equal, data)
+#######################################################################
+# Not_equal
+# ---------
 
+def _test_not_equal(data):
+    """ One iteration of not_equal"""
+    return _test_elemwise(math_ops.not_equal, data)
 #######################################################################
 # Squared_difference
 # ------------------
@@ -915,6 +949,11 @@ def test_all_elemwise():
     _test_forward_elemwise(_test_minimum)
     _test_forward_elemwise(_test_greater)
     _test_forward_elemwise(_test_squared_difference)
+    _test_forward_elemwise(_test_greater_equal)
+    _test_forward_elemwise(_test_less)
+    _test_forward_elemwise(_test_less_equal)
+    _test_forward_elemwise(_test_equal)
+    _test_forward_elemwise(_test_not_equal)
 
 #######################################################################
 # Zeros like