public override void Visit(GradientsNode node)
{
Emit("{\ntensorBackwards(" + node.tensorID + ");\n");
for (int i = 0; i < node.GradVariables.Count; i++)
{
Emit("Tensor* " + node.GradVariables[i] + " = readGradients(" + node.GradTensors[i] + ");\n");
}
Visit(node.Body);
Emit("zeroGradients(" + node.tensorID + ");\n}\n");
}
public override Node VisitGradientsStmt(ML4DParser.GradientsStmtContext context)
{
GradientsNode gradientsNode = new GradientsNode(context.tensor.Text, (LinesNode)Visit(context.body));
for (int i = 0; i < context._gradvar.Count; i++)
{
gradientsNode.GradVariables.Add(context._gradvar[i].Text);
gradientsNode.GradTensors.Add(context._gradtensor[i].Text);
}
return(gradientsNode);
}
public override void Visit(GradientsNode node)
{
SymbolTable.OpenScope();
Symbol tensorDCL = SymbolTable.Retrieve(node.tensorID);
if (SymbolTable.Retrieve(node.tensorID) is null)
{
throw new VariableNotDeclaredException(
$"The variable \"{tensorDCL.Name}\" cannot be assigned, as it has not been declared.");
}
if (tensorDCL.Type != "tensor")
{
throw new Exception($"Variable \"{tensorDCL.Name}\" is not a tensor. Grads can only be derived from tensors.");
}
for (int i = 0; i < node.GradVariables.Count; i++)
{
string gradVar = node.GradVariables[i];
string gradTensor = node.GradTensors[i];
Symbol symbol = SymbolTable.Retrieve(gradTensor);
if (symbol is TensorSymbol tensorSymbol) // Er null check nødvendigt? eller implicit i "is" operator?
{
if (SymbolTable.Retrieve(gradVar) is null)
{
SymbolTable.Insert(gradVar, "tensor", false, tensorSymbol.Rows, tensorSymbol.Columns);
}
else
{
throw new VariableAlreadyDeclaredException(
$"The variable \"{gradVar}\" could not be declared, as it has already been declared in the current or parent scope.");
}
}
else if (symbol is null)
{
throw new VariableNotDeclaredException(
$"The variable \"{gradTensor}\" cannot be assigned, as it has not been declared.");
}
else
{
throw new Exception(
$"Variable \"{symbol.Name}\" is not a tensor. Grads can only be derived from tensors.");
}
}
base.Visit(node);
SymbolTable.CloseScope();
}
public virtual void Visit(GradientsNode node)
{
VisitChildren(node);
}
