[Relay][Frontend][TFlite] Add parses support for unary elemwise ops (a…

…pache#4634)

* [Relay][Frontend][Tflite] Add parses support for unary elemwise ops

* Add generic method to convert unary functions: abs, exp, ceil, floor
  log, sin, cos, sqrt, rsqrt, neg
* Add relevant tests

* Delete excessive underscores as requested in PR review

* Change parameter name as suggested in PR review

python/tvm/relay/frontend/tflite.py

@@ -61,6 +61,16 @@ def __init__(self, model, subgraph, exp_tab):
 
         # Add more operators
         self.convert_map = {
+            'ABS': self.convert_abs,
+            'EXP': self.convert_exp,
+            'FLOOR': self.convert_floor,
+            'CEIL': self.convert_ceil,
+            'LOG': self.convert_log,
+            'SIN': self.convert_sin,
+            'COS': self.convert_cos,
+            'SQRT': self.convert_sqrt,
+            'RSQRT': self.convert_rsqrt,
+            'NEG': self.convert_neg,
             'CONV_2D': self.convert_conv2d,
             'DEPTHWISE_CONV_2D': self.convert_depthwise_conv2d,
             'AVERAGE_POOL_2D': self.convert_average_pool2d,
@@ -495,6 +505,93 @@ def convert_concatenation(self, op):
                     .format('qnn.op.concatenate'))
         return out
 
+    def _convert_unary_elemwise(self, relay_op, op):
+        """Generic method to convert TFLite unary elemwise functions"""
+        try:
+            from tflite.Operator import Operator
+        except ImportError:
+            raise ImportError("The tflite package must be installed")
+
+        assert isinstance(op, Operator)
+        input_tensors = self.get_input_tensors(op)
+        assert len(input_tensors) == 1, "input tensors length should be 1"
+
+        input_tensor = input_tensors[0]
+        in_expr = self.get_expr(input_tensor.tensor_idx)
+        out = relay_op(in_expr)
+
+        return out
+
+    def convert_abs(self, op):
+        """Convert TFLite ABS"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized ABS operator is not supported yet.')
+        return self._convert_unary_elemwise(_op.abs, op)
+
+    def convert_ceil(self, op):
+        """Convert TFLite CEIL"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized CEIL operator is not supported yet.')
+        return self._convert_unary_elemwise(_op.ceil, op)
+
+    def convert_floor(self, op):
+        """Convert TFLite FLOOR"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized FLOOR operator is not supported yet.')
+        return self._convert_unary_elemwise(_op.floor, op)
+
+    def convert_exp(self, op):
+        """Convert TFLite EXP"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized EXP operator is not supported yet.')
+        return self._convert_unary_elemwise(_op.exp, op)
+
+    def convert_log(self, op):
+        """Convert TFLite LOG"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized LOG operator is not supported yet.')
+        return self._convert_unary_elemwise(_op.log, op)
+
+    def convert_sin(self, op):
+        """Convert TFLite SIN"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized SIN operator is not supported yet.')
+        return self._convert_unary_elemwise(_op.sin, op)
+
+    def convert_cos(self, op):
+        """Convert TFLite COS"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized COS operator is not supported yet.')
+        return self._convert_unary_elemwise(_op.cos, op)
+
+    def convert_sqrt(self, op):
+        """Convert TFLite SQRT"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized SQRT operator is not supported yet.')
+        return self._convert_unary_elemwise(_op.sqrt, op)
+
+    def convert_rsqrt(self, op):
+        """Convert TFLite RSQRT"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized RSQRT operator is not supported yet.')
+        return self._convert_unary_elemwise(_op.rsqrt, op)
+
+    def convert_neg(self, op):
+        """Convert TFLite NEG"""
+        if self.is_quantized(op):
+            raise tvm.error.OpNotImplemented(
+                'TFlite quantized NEG operator is not supported yet.')
+        return self._convert_unary_elemwise(_op.negative, op)
+
     def _convert_elemwise(self, relay_op, op):
         """Generic method to Convert TFLite elemwise"""
         try:

tests/python/frontend/tflite/test_forward.py

@@ -616,6 +616,109 @@ def test_forward_concatenation():
          np.arange(6).reshape((2, 1, 1, 3)),
          np.arange(6).reshape((2, 1, 1, 3))], 1)
 
+#######################################################################
+# Unary elemwise
+# --------------
+
+def _test_unary_elemwise(math_op, data):
+    """ One iteration of unary elemwise """
+
+    with tf.Graph().as_default():
+        in_data = array_ops.placeholder(shape=data.shape, dtype=data.dtype, name='in')
+        out = math_op(in_data)
+        compare_tflite_with_tvm(data, ['in:0'], in_data, [out])
+
+#######################################################################
+# Abs
+# ---
+
+def _test_abs(data):
+    """ One iteration of abs """
+    return _test_unary_elemwise(math_ops.abs, data)
+#######################################################################
+# Ceil
+# ----
+
+def _test_ceil(data):
+    """ One iteration of ceil """
+    return _test_unary_elemwise(math_ops.ceil, data)
+#######################################################################
+# Floor
+# -----
+
+def _test_floor(data):
+    """ One iteration of floor """
+    return _test_unary_elemwise(math_ops.floor, data)
+#######################################################################
+# Exp
+# ---
+
+def _test_exp(data):
+    """ One iteration of exp """
+    return _test_unary_elemwise(math_ops.exp, data)
+#######################################################################
+# Log
+# ---
+
+def _test_log(data):
+    """ One iteration of log """
+    return _test_unary_elemwise(math_ops.log, data)
+#######################################################################
+# Sin
+# ---
+
+def _test_sin(data):
+    """ One iteration of sin """
+    return _test_unary_elemwise(math_ops.sin, data)
+#######################################################################
+# Cos
+# ---
+
+def _test_cos(data):
+    """ One iteration of cos """
+    return _test_unary_elemwise(math_ops.cos, data)
+#######################################################################
+# Sqrt
+# ----
+
+def _test_sqrt(data):
+    """ One iteration of sqrt """
+    return _test_unary_elemwise(math_ops.sqrt, data)
+#######################################################################
+# Rsqrt
+# -----
+
+def _test_rsqrt(data):
+    """ One iteration of rsqrt """
+    return _test_unary_elemwise(math_ops.rsqrt, data)
+#######################################################################
+# Neg
+# ---
+
+def _test_neg(data):
+    """ One iteration of neg """
+    return _test_unary_elemwise(math_ops.neg, data)
+#######################################################################
+
+def _test_forward_unary_elemwise(test_op):
+    # functions that need positive input
+    if test_op in {'_test_log', '_test_sqrt', '_test_rsqrt'}:
+        test_op(np.arange(6.0, dtype=np.float32).reshape((2, 1, 3)))
+        test_op(np.arange(6.0, dtype=np.int32).reshape((2, 1, 3)))
+    else:
+        np.array(np.random.uniform(-5, 5, (3, 1)), dtype=np.int32)
+
+def test_all_unary_elemwise():
+    _test_forward_unary_elemwise(_test_abs)
+    _test_forward_unary_elemwise(_test_ceil)
+    _test_forward_unary_elemwise(_test_floor)
+    _test_forward_unary_elemwise(_test_exp)
+    _test_forward_unary_elemwise(_test_log)
+    _test_forward_unary_elemwise(_test_sin)
+    _test_forward_unary_elemwise(_test_cos)
+    _test_forward_unary_elemwise(_test_sqrt)
+    _test_forward_unary_elemwise(_test_rsqrt)
+    _test_forward_unary_elemwise(_test_neg)
 
 #######################################################################
 # Element-wise
@@ -1320,6 +1423,9 @@ def test_forward_mediapipe_hand_landmark():
     # Elemwise
     test_all_elemwise()
 
+    # Unary elemwise
+    test_all_unary_elemwise()
+
     # Zeros Like
     test_forward_zeros_like()