User guide

3-27
Compiling and Elaborating Your Design
-O1
Applies fewer optimizations when generating C code intermediate
files and compiling them. Applying fewer optimizations allows the
C compiler to finish somewhat sooner but the design simulates
somewhat slower without these optimizations.
Compile-Time Options That Speed Up Both Compilation and
Simulation
+nospecify
Tells VCS to ignore specify blocks. If you have extensive specify
blocks this can increase both compilation and simulation speed.
Compile-Time Options That Speed Up Simulation
+delay_mode_zero
Disables all delays. Can increase simulation speed but your
design will simulate differently.
+notimingcheck
Ignores timing check system tasks.
+nbaopt
Removes intra-assignment delays from nonblocking assignment
statements
Compiling for Debugging or Performance
You can use the -Mdir compile-time option to create different
generated file directories, one directory for debugging and another
for performance.
For example, for debugging enter the following vcs command line: