private void decodeCells(GrowableByteBuffer buffer, Tensor.Builder builder, TensorType type, Supplier<Double> supplier) {
        long numCells = buffer.getInt1_4Bytes(); // XXX: Size truncation
        for (long i = 0; i < numCells; ++i) {
            Tensor.Builder.CellBuilder cellBuilder = builder.cell();
            decodeAddress(buffer, cellBuilder, type);
            cellBuilder.value(supplier.get());
        }
    }
Implementation of a sparse binary format for a tensor on the form:

Sorted dimensions = num_dimensions [dimension_str_len dimension_str_bytes]*
Cells = num_cells [label_1_str_len label_1_str_bytes ... label_N_str_len label_N_str_bytes cell_value]*

Note that the dimensions are sorted and the tensor address labels are given in the same sorted order.
Unspecified labels are encoded as the empty string "".

@author geirst
vespajlib/src/main/java/com/yahoo/tensor/serialization/SparseBinaryFormat.java