  Using the mirror theorem [CCIT15], we give a Landau-Ginzburg mirror
description for the big equivariant quantum cohomology of toric Deligne-Mumford
stacks. More precisely, we prove that the big equivariant quantum D-module of a
toric Deligne-Mumford stack is isomorphic to the Saito structure associated to
the mirror Landau-Ginzburg potential. We give a GKZ-style presentation of the
quantum D-module, and a combinatorial description of quantum cohomology as a
quantum Stanley-Reisner ring. We establish the convergence of the mirror
isomorphism and of quantum cohomology in the big and equivariant setting.
