User guide

25-11
Source Protection
• If the encrypted file already exists, VCS outputs an error message
and does not overwrite the existing file. This error message is:
Error: file 'filename.vp' already exists
.
• If an error condition exists in the source file, VCS continues to
create the encrypted file. This file might be corrupt.
To circumvent these problems you can use the +deleteprotected
source protection option. This option disables the check for an
existing encrypted file and deletes the encrypted file if an error
condition occurred in that file.
Permitting CLI/PLI Access to Encrypted Modules
The +pli_unprotected option can be used to disable the normal
PLI/CLI protection that is placed on encrypted modules. The output
files will still be encrypted, but CLI and PLI users will not be prevented
from accessing data in the modules.
This option is used in conjunction with the +protect, +autoprotect
or +auto2protect options. This option only affects the modules in
the current file(s). Modules in files which were encrypted without using
this flag are still fully protected.
This option only affects encrypted verilog files. It is ignored when
encrypting SDF files.
Note: Turning off PLI/CLI protection will allow users of your modules
to access object names and values, etc. In essence, the source
code for your module could be substantially reconstructed using
the CLI debugging commands and PLI acc routines.