( DAC 99 Item 40 ) ----------------------------------------------- [6/25/99]
AN ACE UP THEIR SLEEVE... Scoop time! Synopsys demoed an unannounced
tool called 'PhysOpt' at DAC. And, from the technical descriptions I've
heard, it's a Magma/Monterey-like tool. Chip Architect works managing
designs on the 'hundred(s) of blocks' level. PhysOpt (like Magma and
Monteray) works on the 'millions of cells' level doing highly intelligent
placement as a part of synthesis. (One user I spoke to said "you just do
some extra commands in your DC flow and it handles everything.") Ya
gotta keep watching those Synopsys guys. You never know what's next!
"They got it from IBM, did some work on it, and it didn't work at
first. They got an ex-LSI guy to redo PhysOpt with some special
algorithms and now it works. It's just a few more lines in your
DC script. No need to buy or learn Chip Architect. More importantly,
no more bloody wire load models! All the work is done in their
placement engine which focuses on congestion over timing. (A lot of
placers focus on timing and have later congestion problems.)
My only concern is that Avanti had a front-end placer like this that
didn't match their back-end placement. If Avanti had this problem
in-house, how can Synopsys PhysOpt handle this? They claim PhysOpt
feeds PDEF 2.0 into the Cadence and Avanti routers and it works. The
other issue about placement is you have to tell it about power and
ground. How will front-end Synopsys RTL-to-placement tool do this?
PhysOpt is high on my list of tools to in-house eval."
- an anon engineer
"Synopsys demonstrated Chip Architect. This tool is for chip-level
hierarchical design. PhysOpt will include logic synthesis and key
physical functions to yield gate-level timing-driven placement at
block level. Acquisition of Everest added FlexRoute to tool suite.
Used for top-level detailed gridless route and for block-level global
route. ( http://www.everest-da.com ) A shift towards more Synopsys
tools such as PhysOpt should really only be necessary if Cadence PbOpt
is inadequate. Deployment of tools such as Magma's BlastFusion may
give an additional area reduction but I'd have to see some real
in-house examples before I'd advocate addition of such a tool to our
flow. RTL partitioning a la Tera Systems is also worth evaluating as
could Ultima's clock-skew tool." ( http://www.terasystems.com )
- an anon engineer
"SYNOPSYS - PhysOpt
This tool is used in conjunction with a RTL floorplanner. It reads in
a PDEF file from Synopsys's Design Architect and does Synthesis and
Placement simultaneously. It works on one block at a time. Clock
Tree Synthesis (CTS) is not available, so the final placement would
have to be redone causing possible iterations. You must break the
design in to blocks. They claim that they have a better placer than
Avanti and Cadence, but since they don't route the design and don't
offer CTS, the placement would have to be redone anyway.
This tool is supposed to be available late this year."
- an anon engineer
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