In both Project Mode and Non-Project Mode, incremental place and route mode is
entered when you load the reference design checkpoint using the read_checkpoint -incremental <reference_dcp_file> command. Here,
<reference_dcp_file> specifies the path and
file name of the reference design checkpoint. Loading the reference design checkpoint
with the -incremental option enables the Incremental
Compile design flow for subsequent place and route operations. In Non-Project Mode,
read_checkpoint -incremental must: (1) follow
opt_design and; (2) precede place_design. If using the debug insertion flow the debug core related XDC
commands must precede opt_design.