The Incremental Compile flow is most effective when the revised and reference designs are most similar, preferably with at least 95 percent of the cells matching. Synthesis flows such as Synplify Compile Points minimize the amount of netlist changes resulting from RTL changes. Compile points are logical boundaries across which no optimization might occur. This sacrifices some design performance for predictability, but when combined with Incremental Compile, the resulting flow yields even more run time savings and predictability.
Synplify provides two different compile point flows, which are automatic and manual. In the automatic compile point mode, compile points are automatically chosen by synthesis, based on existing hierarchy and utilization estimates. This is a pushbutton mode. Aside from enabling the flow, there is no action required on your part. To enable, check the Auto Compile Point check box in the GUI or add the following setting to the Synplify project:
set_option -automatic_compile_point 1
The manual compile point flow offers more flexibility, but requires more interaction to
choose compile points. The flow involves compiling the design, then using either the
SCOPE editor Compile Points tab or the define_compile_point
setting.
For further information on compile point flows, see the Synplify online help.