!952 Simplify the `ZeroLikeFillZero` optimization pass

Merge pull request !952 from thlinh/dev_May6th_improve_zero_fill_like_zero

mindspore/ccsrc/optimizer/irpass.cc

@@ -52,8 +52,7 @@ OptimizeIRPassLib::OptimizeIRPassLib() {
   special_op_eliminate_ = MakeSubstitution(SpecialOpEliminater(), "special_op_eliminate",
                                            {prim::kPrimInsertGradientOf, prim::kPrimPrintShapeType,
                                             prim::kPrimGetRefKey, prim::kPrimMirror, prim::kPrimVirtualDiv});
-  zero_like_fill_zero_ =
-    MakeSubstitution(ZeroLikeFillZero(), "zero_like_fill_zero", prim::kPrimZerosLikeTensor, opt::FORCE_RENORM);
+  zero_like_fill_zero_ = MakeSubstitution(ZeroLikeFillZero(), "zero_like_fill_zero", prim::kPrimZerosLikeTensor);
 
   // ops eliminate
   item_tuple_eliminate_ =

mindspore/ccsrc/optimizer/irpass/special_op_eliminate.h

@@ -30,6 +30,7 @@
 namespace mindspore {
 namespace opt {
 namespace irpass {
+
 class SpecialOpEliminater {
  public:
   SpecialOpEliminater()
@@ -156,12 +157,27 @@ class ZeroLikeFillZero : public AnfVisitor {
     if (y_ == nullptr || node->func_graph() == nullptr) {
       return nullptr;
     }
+    if ((y_->abstract() == nullptr) || !y_->abstract()->isa<abstract::AbstractTensor>()) {
+      auto fg = node->func_graph();
+      auto dtype = fg->NewCNode({NewValueNode(PrimDType_), y_});
+      auto shape = fg->NewCNode({NewValueNode(PrimShape_), y_});
+      return fg->NewCNode({NewValueNode(PrimFill_), dtype, shape, NewValueNode(MakeValue(0))});
+    }
+
+    abstract::AbstractTensorPtr tensor_abstract = y_->abstract()->cast<abstract::AbstractTensorPtr>();
+
+    TypePtr tensor_type_ptr = tensor_abstract->element()->BuildType();
+    std::vector<int> tensor_shape = tensor_abstract->shape()->shape();
+
+    tensor::TensorPtr new_tensor_ptr = std::make_shared<tensor::Tensor>(tensor_type_ptr->type_id(), tensor_shape);
+    size_t mem_size = GetTypeByte(tensor_type_ptr) * IntToSize(new_tensor_ptr->ElementsNum());
+    char *data = reinterpret_cast<char *>(new_tensor_ptr->data_c(true));
+    std::memset(data, 0, mem_size);
 
-    auto fg = node->func_graph();
-    auto dtype = fg->NewCNode({NewValueNode(PrimDType_), y_});
-    auto shape = fg->NewCNode({NewValueNode(PrimShape_), y_});
+    auto new_cnode = NewValueNode(new_tensor_ptr);
+    new_cnode->set_abstract(new_tensor_ptr->ToAbstract());
 
-    return fg->NewCNode({NewValueNode(PrimFill_), dtype, shape, NewValueNode(MakeValue(0))});
+    return new_cnode;
   }
 
   void Visit(const AnfNodePtr &node) override { y_ = node; }