// input & output.
// Please note: THIS IS NOT a mathmetically-equivalent transformation and it may
// loose accuracy, so we need to use this very very carefully.
LogicalResult InsertRequantForReduceMean::matchAndRewrite(
    TFL::MeanOp mean_op, PatternRewriter& rewriter) const {
  auto input = mean_op.getInput();
  auto input_type = mlir::dyn_cast_or_null<ShapedType>(input.getType());