There is only one file type that uses the .XSVF extension:
Xilinx Serial Vector Format File
Binary file created for testing programmable logic device (PLD) designs; contains the compact, binary version of an ASCII text .SVF file; used for optimizing the file format of test cases for Xilinx devices.
Xilinx created the XSVF format for optimizing JTAG operations on Xilinx devices. They are used for testing embedded systems.
Updated: November 13, 2010