16.5.3. Dual issue for Advanced SIMD instructions

The NEON engine has limited dual issue capabilities. A load/store, permute, MCR, or MRC type instruction can be dual issued with a Advanced SIMD data-processing instruction. A load/store, permute, MCR, or MRC executes in the NEON load/store permute pipeline. An Advanced SIMD data-processing instruction executes in the NEON integer ALU, Shift, MAC, floating-point add or multiply pipelines. This is the only dual issue pairing permitted.

The NEON engine can potentially dual issue on both the first cycle of a multi-cycle instruction (with an older instruction), and on the last cycle of a multi-cycle instruction (with a newer instruction). Intermediate cycles of a multi-cycle instruction cannot be paired and must be single issue.

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