The design flow for repeating phys_opt_design
design changes is shown in the following figure.
Figure 1. Design Flow when Repeating phys_opt_design Changes
This flow differs from the retrofit flow in two aspects:
- The
iphys_opt_design
changes are incorporated afterplace_design
instead of beforehand. - Both placement changes as well as netlist changes are captured
in the
iphys_opt_design
Tcl script.
Typically, you would use this flow to gain more control over the
post-place phys_opt_design
step. Custom "recipes"
are created from combinations of replayed optimizations and new optimizations
resulting in many possibilities for exploration of design closure.
The write_iphys_opt_tcl
and read_iphys_opt_tcl
commands have a -place
option to replay the placement changes from
phys_opt_design
. This option should be used in
this flow to repeat phys_opt_design
steps after
placement.