Shapewear that doesn’t roll up?

[Tootrousers]

I need some shapewear to go under an evening dress, I want one of the slip types - shorts are no good as I need the line to be smooth all across my stomach from under my bra. Does anyone know if the slips roll up from the bottom when worn or do they stay in place?

I have one from Sainsburys which is great, stays put.

Spanx Higher Power Shorts (I think that's the right name) are awesome and give a lovely smooth line from bra to mid thigh. They don't roll up or down (but are shorts style not a slip).

Thanks both