User guide

13-9
SDF Backannotation
For example, in the /u/designs/mydesign directory are the design.v
and design.sdf files and the sdfhome directory. If you enter the
following command line:
vcs design.v +csdf+precompile +csdf+precomp+dir+sdfhome
+csdf+precomp+ext+_precompiled
VCS creates the design.sdf_precompiled file in the sdfhome
directory.
Now that the precompiled file is not in the default location and does
not have the default filename extension, in subsequent compilations
you must tell VCS its new location and name. There are two ways to
do this:
1. Continue to include the location and name options on the vcs
command line in subsequent compilations. In this example you
would always include +csdf+precomp+dir+sdfhome and
+csdf+precomp+ext+_precompiled.
This method does not require you to make a change in the source
code. You can just add these options to a script you run whenever
you compile your design.
2. Change the filename argument in the $sdf_annotate system
task to the precompiled file. In this example you would change:
$sdf_annotate("design.sdf");
to:
$sdf_annotate("sdfhome/design.sdf_precompiled");