[Quantization] Support zero-size tensor input for quantization flow

src/operator/quantization/dequantize-inl.h

@@ -74,11 +74,18 @@ inline bool DequantizeShape(const nnvm::NodeAttrs& attrs,
   CHECK_EQ(in_attrs->size(), 3U);
   CHECK_EQ(out_attrs->size(), 1U);
 
+  mxnet::TShape dshape = (*in_attrs)[0];
   for (size_t i = 1; i < 3; ++i) {
     SHAPE_ASSIGN_CHECK(*in_attrs, i, mxnet::TShape(1, 1));
   }
 
   SHAPE_ASSIGN_CHECK(*out_attrs, 0, in_attrs->at(0));
+
+  if ((*out_attrs)[0].ndim() > 0) {
+    dshape[0] = ((*out_attrs)[0])[0];
+    SHAPE_ASSIGN_CHECK(*in_attrs, 0, dshape);
+  }
+
   return shape_is_known(out_attrs->at(0));
 }
 

src/operator/quantization/quantize-inl.h

@@ -119,13 +119,20 @@ inline bool QuantizeShape(const nnvm::NodeAttrs& attrs,
   CHECK_EQ(in_attrs->size(), 3U);
   CHECK_EQ(out_attrs->size(), 3U);
 
+  mxnet::TShape dshape = (*in_attrs)[0];
   for (size_t i = 1; i < 3; ++i) {
     SHAPE_ASSIGN_CHECK(*in_attrs, i, mxnet::TShape(1, 1));
   }
 
   SHAPE_ASSIGN_CHECK(*out_attrs, 0, in_attrs->at(0));
-  SHAPE_ASSIGN_CHECK(*out_attrs, 1, mxnet::TShape{1});
-  SHAPE_ASSIGN_CHECK(*out_attrs, 2, mxnet::TShape{1});
+  SHAPE_ASSIGN_CHECK(*out_attrs, 1, mxnet::TShape(1, 1));
+  SHAPE_ASSIGN_CHECK(*out_attrs, 2, mxnet::TShape(1, 1));
+
+  if ((*out_attrs)[0].ndim() > 0) {
+    dshape[0] = ((*out_attrs)[0])[0];
+    SHAPE_ASSIGN_CHECK(*in_attrs, 0, dshape);
+  }
+
   return shape_is_known(out_attrs->at(0));
 }
 

src/operator/quantization/quantize_v2-inl.h

@@ -109,9 +109,16 @@ static inline bool QuantizeV2Shape(const nnvm::NodeAttrs &attrs, std::vector<TSh
   CHECK_EQ(in_attrs->size(), 1U);
   CHECK_EQ(out_attrs->size(), 3U);
 
+  mxnet::TShape dshape = (*in_attrs)[0];
   SHAPE_ASSIGN_CHECK(*out_attrs, 0, in_attrs->at(0));
-  SHAPE_ASSIGN_CHECK(*out_attrs, 1, TShape{1});
-  SHAPE_ASSIGN_CHECK(*out_attrs, 2, TShape{1});
+  SHAPE_ASSIGN_CHECK(*out_attrs, 1, TShape(1, 1));
+  SHAPE_ASSIGN_CHECK(*out_attrs, 2, TShape(1, 1));
+
+  if ((*out_attrs)[0].ndim() > 0) {
+    dshape[0] = ((*out_attrs)[0])[0];
+    SHAPE_ASSIGN_CHECK(*in_attrs, 0, dshape);
+  }
+
   return !shape_is_none(out_attrs->at(0));
 }
 

src/operator/quantization/quantized_activation.cc

@@ -115,6 +115,8 @@ the float32 data into int8.
 .add_argument("max_data", "NDArray-or-Symbol", "Maximum value of data.")
 .add_arguments(ActivationParam::__FIELDS__());
 
+// TODO(zhiyuan): remove below comment once the accuracy issue of this op is addressed.
+#if 0
 NNVM_REGISTER_OP(Activation)
 .set_attr<FQuantizedOp>("FQuantizedOp", [](const NodeAttrs& attrs) {
   ActivationParam param;
@@ -133,6 +135,7 @@ NNVM_REGISTER_OP(Activation)
   }
   return node;
 });
+#endif
 
 }  // namespace op
 }  // namespace mxnet

src/operator/quantization/quantized_elemwise_add.cc

@@ -125,6 +125,8 @@ and max thresholds representing the threholds for quantizing the float32 output
 .add_argument("rhs_max", "NDArray-or-Symbol", "6th input");
 
 
+// TODO(zhangrong): remove below comment once the accuracy issue of this op is addressed.
+#if 0
 NNVM_REGISTER_OP(elemwise_add)
 .set_attr<FQuantizedOp>("FQuantizedOp", [](const NodeAttrs& attrs) {
   nnvm::NodePtr node = nnvm::Node::Create();
@@ -136,6 +138,7 @@ NNVM_REGISTER_OP(elemwise_add)
   }
   return node;
 });
+#endif
 
 }  // namespace op
 }  // namespace mxnet

src/operator/quantization/quantized_fully_connected.cc

@@ -47,36 +47,42 @@ bool QuantizedFullyConnectedShape(const nnvm::NodeAttrs& attrs,
   CHECK_EQ(in_shape->size(), num_inputs * 3);
   CHECK_EQ(out_shape->size(), 3U);
 
-  CHECK(shape_is_known(in_shape->at(0)))
-    << "QuantizedFullyConnectedOp input data shape must be given";
-  const mxnet::TShape& dshape = in_shape->at(0);
+  mxnet::TShape dshape = (*in_shape)[0];
+  // require data ndim to be known
+  if (!mxnet::ndim_is_known(dshape)) return false;
+
   index_t num_input;
   if (!param.flatten) {
     num_input = dshape[dshape.ndim() - 1];
   } else {
     num_input = dshape.ProdShape(1, dshape.ndim());
   }
 
-  TShape wshape = Shape2(param.num_hidden, num_input);
+  mxnet::TShape wshape = Shape2(param.num_hidden, num_input);
   SHAPE_ASSIGN_CHECK(*in_shape, 1, wshape);
   if (!param.no_bias) {
     mxnet::TShape bshape = Shape1(param.num_hidden);
     SHAPE_ASSIGN_CHECK(*in_shape, 2, bshape);
   }
 
   for (size_t i = num_inputs; i < 3 * num_inputs; ++i) {
-    SHAPE_ASSIGN_CHECK(*in_shape, i, mxnet::TShape{1});
+    SHAPE_ASSIGN_CHECK(*in_shape, i, mxnet::TShape(1, 1));
   }
 
   if (!param.flatten) {
-    TShape result_shape(dshape);
+    mxnet::TShape result_shape(dshape);
     result_shape[dshape.ndim() - 1] = param.num_hidden;
     SHAPE_ASSIGN_CHECK(*out_shape, 0, result_shape);
   } else {
     SHAPE_ASSIGN_CHECK(*out_shape, 0, Shape2(dshape[0], param.num_hidden));
   }
   SHAPE_ASSIGN_CHECK(*out_shape, 1, mxnet::TShape(1, 1));
   SHAPE_ASSIGN_CHECK(*out_shape, 2, mxnet::TShape(1, 1));
+
+  if ((*out_shape)[0].ndim() > 0) {
+    dshape[0] = ((*out_shape)[0])[0];
+    SHAPE_ASSIGN_CHECK(*in_shape, 0, dshape);
+  }
   return true;
 }