User guide

E-64
PLI Access Routines
Access Routines for Source Protection
The enclib.o file provides a set of access routines that you can use
to create applications which directly produce encrypted Verilog
source code. Encrypted code can only be decoded by the VCS
compiler. There is no user-accessible decode routine.
Note that both Verilog and SDF code can be protected. VCS knows
how to automatically decrypt both.
VCS provides the following routines to monitor the port activity of a
device:
vcsSpClose
This routine frees the memory allocated by
vcsSpInitialize(). See "vcsSpClose" on page E-68 for
details.
vcsSpEncodeOff
This routine inserts a trailer section containing the
’endprotected compiler directive into the output file. It also
toggles the encryption flag to false so that subsequent calls to
vcsSpWriteString() and vcsSpWriteChar() will NOT
cause their data to be encrypted. See "vcsSpEncodeOff" on page
E-68 for details.
vcsSpEncodeOn
This routine inserts a trailer section containing the ’protected
compiler directive into the output file. It also toggles the encryption
flag to false so that subsequent calls to vcsSpWriteString()
and vcsSpWriteChar() will have their data encrypted. See
"vcsSpEncodeOn" on page E-69 for details.