Before revision:  Tiramisu relies on a flexible representation based on the polyhedral model and explicitly uses a well-defined four-level IR that allows full separation between the algorithms, loop transformations, data-layouts , and communication.
After revision:  Tiramisu relies on a flexible representation based on the polyhedral model and explicitly uses a well-defined four-level intermediate representation that allows full separation between the algorithms, loop transformations, data-layouts , and communication.