Binding multiple textures to a cudaArray

I want to bind two 2D texture references to a region of memory allocated as a cudaArray. The array width and height are w and h=h1+h2. The first texture reference is to point to area of size wxh1 and the second one to the area of size wxh2 starting at row index h2 in the cudaArray. This is simplified version of what I need to do and we want to avoid allocating two CUDA Arrays.

Here is the pesudo code

texture<float, 2> tex1;
texture<float, 2> tex2;

cudaArray *cuArr;
cudaChannelFormatDesc cdFloat = cudaCreateChannelDesc();

cudaMallocArray(&cuArr, &cdFloat, w, h);

// now the binding to tex1 and tex2.
// tex1 to bind to the beginning of the cuArr and tex2 to bind to the beginning of row h1.

According to CUDA programming guide:
‘Several distinct texture references might be bound to the same texture or to textures that overlap in memory.’
How?

Your comments are appreciated.