/// <summary>
/// By default, and expression can have upto only one user. For multiple users, we will need to introduce temporary WriteIndentifier expressions.
/// We might have statements (e.g. if) that use the result, so type should be Node and not Expression
/// </summary>
public override void AddUser(Node newUser)
{
if (User == null)
{
base.AddUser(newUser);
}
else
{
var currUser = User;
var writeTemp = currUser as WriteTemporaryExpression;
if (writeTemp == null)
{
base.RemoveUser(currUser); //next line will call this.AddUser again, so should null it beforehand
writeTemp = new WriteTemporaryExpression(this);
Debug.Assert(User == writeTemp, "Invalid situation!");
currUser.Replace(this, writeTemp);
writeTemp.AddUser(currUser);
}
else
{
//already a temporary is assigned
}
newUser.Replace(this, writeTemp);
writeTemp.AddUser(newUser);
}
}
/// <summary>
/// By default, and expression can have upto only one user. For multiple users, we will need to introduce temporary WriteIndentifier expressions.
/// We might have statements (e.g. if) that use the result, so type should be Node and not Expression
/// </summary>
public override void AddUser(Node newUser)
{
if (User == null)
base.AddUser(newUser);
else
{
var currUser = User;
var writeTemp = currUser as WriteTemporaryExpression;
if (writeTemp == null)
{
base.RemoveUser(currUser); //next line will call this.AddUser again, so should null it beforehand
writeTemp = new WriteTemporaryExpression(this);
Debug.Assert(User == writeTemp, "Invalid situation!");
currUser.Replace(this, writeTemp);
writeTemp.AddUser(currUser);
}
else
{
//already a temporary is assigned
}
newUser.Replace(this, writeTemp);
writeTemp.AddUser(newUser);
}
}
public Temporary Declare(WriteTemporaryExpression node)
{
Temporary temp;
for (var i = TemporariesCount - 1; i >= 0; --i)
{
temp = Temporaries[i];
if (temp.Node == node)
return temp;
}
//Did not find it, so need to declare it
if (Temporaries == null)
Temporaries = new Temporary[5];
if (TemporariesCount >= Temporaries.Length)
Array.Resize(ref Temporaries, TemporariesCount * 2);
temp = Temporaries[TemporariesCount];
if (temp == null)
Temporaries[TemporariesCount] = temp = new Temporary();
else
temp.Node = null; //This is to signal the node it should recalculate
++TemporariesCount;
return temp;
}
public override void Visit(WriteTemporaryExpression node)
{
var local = _localVars.Get(node);
if (local == null)
{
//First visit
Debug.Assert(node.Users != null && node.Users.Count > 1, "Invalid situation, temporary must have more than one user!");
VisitNode(node.Value);
_ilGen.Dup();
if (_result.ValueType == mdr.ValueTypes.DValueRef)
{
local = _localVars.Declare(mdr.ValueTypes.DValue, node);
_ilGen.Ldloca(local);
_ilGen.Call(Types.Operations.Assign.Get(_result.ValueType));
}
else if (_result.ValueType == mdr.ValueTypes.Unknown || _result.ValueType == mdr.ValueTypes.Any)
{
local = _localVars.Declare(_result.Type, node);
_ilGen.Stloc(local);
}
else
{
local = _localVars.Declare(_result.ValueType, node);
_ilGen.Stloc(local);
}
}
else
{
//this was already visited
if (local.LocalType == Types.DValue.TypeOf)
{
_ilGen.Ldloca(local);
_result.ValueType = mdr.ValueTypes.DValueRef;
}
else
{
_ilGen.Ldloc(local);
_result.Type = local.LocalType;
}
}
}
public override void Visit(WriteTemporaryExpression node)
{
Visit((Reference)node);
VisitNode(node.Value);
}
public override void Visit(WriteTemporaryExpression node)
{
if (!VisitedWriteTemporaries.Contains(node))
{
base.Visit(node);
node.ValueType = GetType(node);
VisitedWriteTemporaries.Add(node);
}
}
internal static mdr.ValueTypes GetType(WriteTemporaryExpression expression) { return expression.Value.ValueType; }
public override void Visit(WriteTemporaryExpression node)
{
Debug.Assert(node.Users.Count > 1, "Invalid situation, temporary must have more than one user!");
WriteTemporaryInfo info;
if (_writeTemporaries.TryGetValue(node, out info))
{
//this was already visited
info.Readers.Add(new WriteTemporaryInfo.ReaderInfo()
{
ReaderICIndex = ReserveNewICIndex(),
DestinationValueIndex = _stackModel.StackPointer,
});
_stackModel.Push(1);
}
else
{
//First visit
VisitNode(node.Value);
info = new WriteTemporaryInfo()
{
WriterICIndex = ReserveNewICIndex(),
SourceValueIndex = _stackModel.StackPointer - 1, //load the top item, but no pop or push
};
_writeTemporaries.Add(node, info);
}
}
public override void Visit(WriteTemporaryExpression node)
{
Visit((Reference)node);
}
public abstract void Visit(WriteTemporaryExpression node);
public override void Visit(WriteTemporaryExpression node)
{
Debug.Assert(node.Users.Count > 1, "Invalid situation, temporary must have more than one user!");
var local = _localVars.Get(node);
if (local != null)
{
//this was already visited
_ilGen.Ldloca(local);
Call(Types.Operations.Stack.LoadDValue, 0, 1);
}
else
{
//First visit
VisitNode(node.Value);
local = _localVars.Declare(mdr.ValueTypes.DValue, node);
LoadStackItem(-1); //load the top item, but no pop or push
_ilGen.Ldloca(local);
_ilGen.Call(Types.Operations.Assign.Get(mdr.ValueTypes.DValueRef));
}
}
public override void Visit(WriteTemporaryExpression node) { AssignToImplicitReturn(node); }
