In the Vivado IDE, you can add simulation sources to the project for behavioral simulation of an RTL Project. Simulation source files include hardware description language (HDL)-based test bench files to use as a stimulus for simulation. Simulation sources are used for behavioral simulation in the Vivado simulator.
The Vivado IDE stores simulation source files in simulation sets that display in folders in the Sources window, and are remotely referenced or stored in the local project directory. Simulation sets enables you to define different sources for different simulation configurations. For example, one simulation source can provide stimulus for behavioral simulation using one test bench while another can contain a different test bench. When adding simulation sources to the project, you can specify which simulation set into which to add files.