Problems porting deprecated DataFlow to new IR DataFlow (field-involved)

Hello there, I'm trying to port my query from deprecated DataFlow to new IR DataFlow. However, due to the lack of clear documentation, I got myself stuck in the below scenarios.

The example C code is like below

```c
1 extern int** func1(int len);
2 extern void func2(int *d[]);
3
4 struct st {
5 int **data;
6 };
7
8 void testfunc(struct st *ptr)
9 {
10 int **dp;
11 ptr->data = func1(16);
12 dp = ptr->data;
13 func2(dp);
14 }
```

While the query using old DataFlow is like the one below

```ql
import cpp
import semmle.code.cpp.Print
import semmle.code.cpp.dataflow.DataFlow

from DataFlow::Node source, DataFlow::Node end
where
exists(FunctionCall fc | fc.getTarget().hasName("func1") | source.asExpr() = fc)
and DataFlow::localFlow(source, end)
select source, source.getLocation(), end, end.getLocation()
```

In a nutshell, I want to use dataflow to trace the return value of calling `func1`. It's obvious that the analysis should track the flow to call of `func2`.
Running that query turned out well, I got result an entry like:

```
| call to func1 | file:///.../test.c:11:14:11:18 | dp | file:///.../test.c:13:8:13:9 |
```

Then, I port this query to the new IR Dataflow by change

```ql
import semmle.code.cpp.dataflow.DataFlow
```

to

```ql
import semmle.code.cpp.dataflow.new.DataFlow
```

And I cannot get the expected result but only the source node itself

```
| call to func1 | file:///.../test.c:11:14:11:18 | call to func1 | file:///.../test.c:11:14:11:18 |
```

I also try to replace the `asExpr` with some statements that don't exist in old DataFlow, such as `asConvertedExpr()`, `asIndirectExpr()`, etc. But no one works out.

I wonder whether this is my problem with using the new IR DataFlow, or the expected incapability of the new IR DataFlow to handle field-involved expression. If I change the example code to the below simple case:

```c
extern int** func1(int len);
extern void func2(int *d[]);

void testfunc()
{
int **dp1, **dp2;
dp1 = func1(16);
dp2 = dp1;
func2(dp2);
}
```

Both the deprecated DataFlow and new DataFlow can track the call to `func2`.

**Please help me write the new IR DataFlow query that can track the field-involved case. Thanks in advance.**