To better analyze optimization results, use the -debug_log option to
see additional details of the logic affected by opt_design
optimization. The log displays additional messages of logic that is reduced due to
constant values and loadless logic that is subject to removal.
The log also displays detailed messages about optimizations that are prevented due to
constraints. Use the -verbose option to see full details of all logic optimization
performed by opt_design. The -verbose option is
off by default due to the potential for a large volume of additional messages. Use
the -verbose option if you believe it might be helpful.
Recommended: To improve tool
run time for large designs, use the
-verbose option only in shell
or batch mode and not in the GUI mode.Important: The
opt_design command operates on the in-memory
design. If run multiple times, the subsequent run optimizes the results of the
previous run. Therefore you must reload the synthesized design before adding either
the -debug_log or -verbose options.