The IS-curve in the AS-AD model
The IS-curve is not affected by P in the AS-AD model
We can define an IS-curve in the AS-AD model similarly to the IS-LM model: it will give us all combinations of R and Y where goods market is in equilibrium, which is, where aggregate demand is equal to GDP, Y_{D}(Y, R) = Y.
Since P doesn't affect any part of goods market, P won't affect the IS curve. IS curve in the AS-AD model is exactly the same as IS-curve in IS-LM model.