If you want a hedge the rooted branches will contribute to that. Personally I'd remove all the landscape fabric before weeds root on top of it. Once the fabric is gone the rosemary can root into the mulch and it will not matter.

whew! i was worried the rosemary branches rooted was going to go in a different direction lol.i tried mulch without the fabric and i was getting weeds coming out of the mulch.there is alot of different types of weeds and grass here.it's a nightmare lol.what about drain rocks on top of the fabric?

The direction of the rooting branches is entirely under your control. Just pull up any which grow out of line.

The more stuff you pile on top of fabric the worse mess you'll get. I would still get rid of it and just get used to the idea that weeding is an integral part of gardening. Thick organic mulch will help but weeds are weeds precisely because they are so good at finding places to grow. There is no such thing as no maintenance gardening.