How to match copy pattern while using dma_copy pragma

Hello, while I try to compile resnet-18, I met the problem like this:

Check failed: MatchCopyPattern(op->body, &ret) == false: Cannot match copy pattern of // attr [mdata_pad.local.inp_buffer] storage_scope = "local.inp_buffer"
allocate mdata_pad.local.inp_buffer[int8 * 16 * 256]
for (ax0, 0, 16) {
  for (ax1, 0, 256) {
    mdata_pad.local.inp_buffer[((ax0*256) + ax1)] = tir.if_then_else((((i.outer*16) + ax0) < 49), placeholder.local.input_bufferA[(((floordiv(ax1, 16)*182) + (floordiv(((i.outer*16) + ax0), 7)*26)) + (floormod(((i.outer*16) + ax0), 7)*2))], (placeholder.local.input_bufferA[(((floordiv(ax1, 16)*182) + (floordiv(((i.outer*16) + ax0), 7)*26)) + (floormod(((i.outer*16) + ax0), 7)*2))] - placeholder.local.input_bufferA[(((floordiv(ax1, 16)*182) + (floordiv(((i.outer*16) + ax0), 7)*26)) + (floormod(((i.outer*16) + ax0), 7)*2))]))
  }
}

the error report shows that I violet the copy pattern rule of TVM, but I don’t know how can I match the rule. Thank you if you have any idea.