Get real cart subtotal for cart promotion

I wrote a condition for a cart promotion in a new promotion engine. According to it, if cart subtotal is greater than ,for example, 80, apply a discount to cart. (cart subtotal is assigned in a custom RAO populator)

I have also product promotion together with the cart total. According to the product promotion, if the product is added to cart, apply a discount on the cart.

My problem is that if I have product promotion with the cart promotion, cart subtotal remains unchanged and cart promotion applies according to old subtotal.

Let me give an example.

Prod Promotion: P1 discount %50 on the price of same product ( Let the normal price of the product be 100 )

Cart Promo: C1 discount 10$ on cart when cart subtotal is greater than 100.

When I add it to cart, my old subtotal is 100 but actually is 50 before the cart promotion applies. So it is wrong.

I want to know real cart subtotal in cartRAO in order to apply cart promotion properly.

How to solve my problem?