  Quantum computing is a hotspot technology for its potential to accelerate
specific applications by exploiting quantum parallelism. However, current
physical quantum computers are limited to a relatively small scale, simulators
based on conventional machines are significantly relied on to perform quantum
computing research. The straightforward array-based simulators require a
tremendous amount of memory that increases exponentially with respect to the
number of qubits. To mitigate such computing resource concerns, decision
diagram based simulators were proposed that can efficiently exploit data
redundancies in quantum states and operations. In this paper, we study two
classes of quantum circuits on which the state-of-the-art decision diagram
based simulators failed to perform well in terms of simulation time. We also
propose a simple and powerful reorder trick to boost the simulation of such
quantum circuits. Preliminary evaluation results demonstrate the usefulness of
the proposed trick. Especially, for the Quantum Phase Estimation circuits, the
proposed trick achieved speedups up to 313.6x compared to a state-of-the-art
approach that relies on an auxiliary tool to optimize simulation order.
