AscendC::Add(zLocal, xLocal, yLocal, TILE_LENGTH) — this single line is the entire point of the kernel. It runs on the Vector unit and adds all TILE_LENGTH numbers of xLocal and yLocal in one SIMD instruction, writing to zLocal. This is the Ascend equivalent of the GPU's out[idx] = a[idx] + b[idx] — except the GPU does one element per thread, while here one instruction does the whole tile.
very important