( ESNUG 382 Item 1 ) -------------------------------------------- [11/15/01]
Subject: ( ESNUG 381 ) PhysOpt, Cadence PKS, Silicon Perspectives, Plato
> I've heard through the rumor mill that Cadence paid between $200 million
> and $300 million (partially in Cadence stock) for Silicon Perspectives.
> Now you might ask why would Cadence pay such a high price for SPC? From
> my viewpoint, it's a pretty easy decision. PKS, as a product, just hasn't
> caught on with users yet. (Compare those 250+ PhysOpt tape-outs to PKS'
> 13 tape-outs and you'll see what I mean.) ... Buying Silicon Perspectives
> lets Cadence back into the 'power user' design flow.
>
> - John Cooley
From: [ Trojan Man ]
Hi, John,
I hope your assesment on PKS turns out untrue. We're using PhysOpt for some
parts of our design and sometimes I think the tool creates more problems
then it solves. Synopsys has been very supportive in our using PhysOpt, but
we are mostly doing some things in a non-Synopsys recommended way:
1.- Using DC (not PhysOpt) to get from RTL to gates. (Maybe they do
recommend this for large designs. I'm not sure.)
2.- Have a lot of clock gating logic (for functionality not just power.)
3.- We use transparent latches in many cases.
Quite often Synopsys comes to us with a solution to our PhysOpt issues, but
they're so involved, we don't implement them. Instead we just stick to our
what works now workarounds. (I'm trying to say that I may not be giving
PhysOpt a completely fair shake here.) Our biggest PhysOpt problems are:
1.- Placement congestion -- Blocks that would route with SE placement
needed to be made larger by 10% to 20% to route w/ PhysOpt placement.
2.- Placement of clock gating elements -- their Tcl scripts to solve
this on SolvNet are incomplete.
3.- DEF out of db2def -- DEF headers and certain cell attributes are
not retained from the original input DEF. We are not able to take
the results straight into Warp Route without making modifications
to the file.
4.- Runtime -- 50 K instances used to take overnight. We had do more
floorplanning because of these runtime issues. It now takes 5 hours
to do 15 K to 20 K instances in PhysOpt. I guess that's OK, but it
required floorplanning our design into 20 K blocks.
5.- name_rules / uniquify bug -- PhysOpt behaves differently than DC; we
got multiple instances with the same name.
6.- PhysOpt doesn't automatically handle propagation of clocks through our
gating logic. It's not easy to get PhysOpt to understand our complex
clock gating logic. It's handles NANDs and NORS; anything bigger (or
more complex) and PhysOpt is lost.
Again, on some of these problems we have not fully explored the fixes from
our Synopsys FAE, but right now we are evaluating PKS. I think PKS would
probably help with 1, 3 and 5. PKS will probably score the same as PhysOpt
on issues 2, 4 and 6. We expect PKS will also definitely have other issues
that we have never seen as well. We just hope that PKS is available as a
back-up tool if PhysOpt fails to deliver. Please keep me anon.
- [ Trojan Man ]
---- ---- ---- ---- ---- ---- ----
From: [ Msg 10159 on Yahoo CDN ]
CDN's buy of SPC is brilliant not only in that it gives CDN a first-class
tool, but more in that it breaks up the purported SPC & Plato alliance.
Without SPC, Plato is "just another router" (albeit a very good one), and
its influence will be much dampened.
CDN's real intent is to prevent SPC + Plato from happening, as it'd pose a
powerful threat to CDN's (and AVNT's) core business.
My prediction? From now on CDN will start actively making SPC *NOT* working
with Plato. Too bad for Plato...
- [ Msg 10159 on Yahoo CDN ]
---- ---- ---- ---- ---- ---- ----
From: [ Msg 10162 on Yahoo CDN ]
Are we going to see the same kind of bail-o-rama that we saw when CDN bought
Ambit? Most of the talent from Ambit left in weeks (one friend at Ambit
told me he left as soon as humanly and contractually possible) or are there
"golden handcuffs"? Many of the SPCers are "former CDNers" so they are very
likely to become "former CDNers againers"...
- [ Msg 10162 on Yahoo CDN ]
---- ---- ---- ---- ---- ---- ----
From: [ Msg 10166 on Yahoo CDN ]
On the vesting schedule - It all depends on how good a negotiator the SPC
team was. I rank them among the best, especially with hindview of what
Prakash was able to do with Ambit. I've heard that much of the SPC vesting
is immediate with a small kicker for staying similar of Ambit, at least for
the executroids.
- [ Msg 10166 on Yahoo CDN ]
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