bug fix in tensor deletion

source/network/XBackwardMath.cpp

@@ -760,7 +760,7 @@ void XMathGrad::GradMultiplyDim(XTensor * node)
         DelTensorBuf(interGrad);
     }
 
-    DelTensor(bGradTMP);
+    DelTensorBuf(bGradTMP);
     node->visitMark = NODE_FINISHED;
 }
 
@@ -902,7 +902,7 @@ void XMathGrad::GradPower(XTensor * node)
     _ScaleAndShiftMe(b, p);
     _Multiply(node->grad, b, a->grad, 1.0F);
 
-    DelTensor(b);
+    DelTensorBuf(b);
 
     node->visitMark = NODE_FINISHED;
 }
@@ -1229,7 +1229,7 @@ void XMathGrad::GradReduceSum(XTensor * node)
     _Unsqueeze(node->grad, b, dim, n);
     _Sum(a->grad, b, a->grad);
 
-    DelTensor(b);
+    DelTensorBuf(b);
 
     node->visitMark = NODE_FINISHED;
 }