[__arm_]vst2q[_s8]

Saves two 64-bit contiguous blocks of data to memory made up of multiple parts of 2 source registers. The parts of the source registers written to, and the offsets from the base address register, are determined by the pat parameter. If the instruction is executed 2 times with the same base address and source registers, but with different pat values, the effect is to interleave the specified registers with a stride of 2 and to save the data to memory. The base address register can optionally be incremented by 32.