ECO and Incremental route

Hello ,

you can use "ecoPlace -fixPlacedInsts " option to don`t move the instances which was already placed.
How ever when "-fixPlacedInsts " option is not specified in order to place unplaced cell in the optimal position , the instances which was already placed and has PLACED status may move .
to Route nets which were changed by ECO use
encounter > setnanoRouteMode routeWithECO tru
encounter > globalDetailRoute
When the variable "routeWithECO true " is set , only nets with differs its wire connection and net connection are rerouted.
If routing doesn`t complete with "routeWithECO true " option , then route with "routeWithECO false " in this case all nets are re-routed ,but the course of the wire which is already routed doesn`t change roughly



In general Soc can handle 3 types of ECO flow like
1. Post -layout ECO
2. post -Mask ECO
3. Smart ECO

How ever you have not mentioned which one you are using and flow involved to do it ??

FYI .

As we know the procedure will generate use ecoCompareNetlist and loadECO commands .
ecoDefIn :
Restores physical information from an old design and compares this
information with the design in memory. This command uses the specified
DEF file
- New cells and nets

Cells and nets that exist in memory but not in the DEF file become
unplaced.

- Deleted cells or nets

Cells and nets that exist in the DEF file but not in memory are dis-
carded.

- Modified nets

Nets found both in the DEF file and in memory, but whose connections
are different, are marked as "modified" for further processing during
ecoRoute.

- Matched cells/nets

Nets and cells that exist both in the DEF file and in memory, and have
the same connections, are placed as described in the DEF file. This
includes the soft matching capability used in defIn.
- In post-mask mode (with the -postMask parameter), the software can
only change nets, not cells. This command behaves as follows:

- New added cells and nets

Cells and nets that exist in memory but not in the DEF file become
unplaced. Later, these cells but will be mapped to spare cells when you
use ecoPlace -useSpareCells.

- Deleted cells

Cells and instances that exist in DEF but not in memory are added to a
spare cell list in Encounter: They are not discarded. Deleted cells are
renamed with their original name and the suffix you specify. The
default suffix is _SPARE. For example, cellA is renamed cellA_SPARE.
The software retains deleted nets and their routing, which ecoRoute
reroutes later.

- Deleted nets

Nets that exist in DEF but not in memory are kept and processed later
when you use the ecoRoute command.

- Modified nets

Same behavior as in the pre-mask mode.

- Matched cells and nets

Same behavior as in the pre-mask mode.

- Physical cells

Cells that exist in the DEF file but not in memory, which are marked
with +SOURCE DIST in the DEF file, are restored.