  This paper investigates a device-to-device (D2D) cooperative computing
system, where an user can offload part of its computation task to nearby idle
users with the aid of an intelligent reflecting surface (IRS). We propose to
minimize the total computing delay via jointly optimizing the computation task
assignment, transmit power, bandwidth allocation, and phase beamforming of the
IRS. To solve the formulated problem, we devise an alternating optimization
algorithm with guaranteed convergence. In particular, the task assignment
strategy is derived in closed-form expression, while the phase beamforming is
optimized by exploiting the semi-definite relaxation (SDR) method. Numerical
results demonstrate that the IRS enhanced D2D cooperative computing scheme can
achieve a much lower computing delay as compared to the conventional D2D
cooperative computing strategy.
