Hi,
Not sure what you mean by "massive data". Are you refering to a large quantity of numeric data or a particular type of data?
You could write a testbench that accesses your "masive data" files (Assuming you have the massive data in some kind of data file!). VHDL provides a textio package that allows the testbench to access files. Although it has limited functionality, you may be able to write a testbench to parse the file into the form you require.
If not then maybe a bit of C/Perl etc preprocessing to make the file easier to handle in VHDL might be beneficial.