FMCAD 2027: Will the FM Have a Real Impact on the CAD?

Carl Pixley

Disclaimer: These opinions are mine alone and not necessarily Synopsys’. Also, I tend toward hyperbole.

November 6, 2007

© 2006 Synopsys, Inc. (2)

Proposition Zero

• Formal Methods ALREADY have had a major effect on CAD. Most CAD tools have some form of

mathematical reasoning “built in”. Chips cannot be implemented without

equivalence checking. Constraint Based Verification is very

common: It is based upon formal principles.

© 2006 Synopsys, Inc. (3)

It’s hard to make a buck in EDA.• My perspective is from the EDA industry.

• For the last ~5 years the whole EDA industry has made about $5B and it really has not changed very much.

• The big EDA companies have volume purchase agreements with our customers – often the deals are Texas “family style”, i.e., all you can eat for one price.

• This is good for financial stability but not so good for growth and innovation.

© 2006 Synopsys, Inc. (4)

Proposition One• Automated Synthesis from algorithm

(transaction) level to RTL cannot be accepted without formal HL-to-RTL equivalence. Design managers will not accept the results

of HL synthesis without a formal tool to check independently.

Simulation is well-known to not be sufficient.

It is a hard problem but we are doing it.

© 2006 Synopsys, Inc. (5)

Commentary• There are two distinct problems in C2RTL

equivalence (1) Ad hoc: one set of people construct the C

models by hand and another set of people implement the C models in RTL

(2) Automated synthesis: C models made by-hand and RTL automatically derived from it.

• (1) is MUCH harder than (2). We have done both. (1) takes more effort

and requires information that is hard to get sometimes (e.g., proper and complete constraints).

© 2006 Synopsys, Inc. (6)

Proposition Two

• Assertion/constraint – based verification has a poor cost/benefit ratio – so far.

• Caveats: Some critical parts just have to have formal

analysis to avoid disaster, e.g., bus controllers.

EDA companies now sell tools in this space and make some money from it but not a lot.

Development of methodologies and libraries of assertions help but still it is a hard sell.

© 2006 Synopsys, Inc. (7)

Proposition Three• ESL will happen because it has to.

• Case in point: the cellphone Combines RF, audio (MP3), video, full-

motion video, GPS, net access, PDA, security….

All of this has to be done with low power to conserve battery life.

Caveat: On the other hand cellphones often don’t work and aren’t life critical usually.

• Time to market dictates that Cellphones must be designed (and verified) quickly.

© 2006 Synopsys, Inc. (8)

Commentary• My friend and colleague Jin Yang (Intel)

believes he has found a theoretical foundation for designing a modern microprocessor (out-of-order, speculative, superscalar, etc.) in a correct-by-construction, customizable and modular manner.

• This MIGHT be the effect on design in 2027 that will happen..

© 2006 Synopsys, Inc. (9)

Last year’s prediction:Synthesizable TB

• Synthesizing testbenches is possible!

• It looks like Eve (and probably other emulation companies) have done a lot in this direction.

• Score one for me!

© 2006 Synopsys, Inc. (10)

Predictions for 2027• The state of electronics may be so

radically different from today that we may not recognize it.

• By 2027 pre-formally-verified IP will be the norm for designs. Interfaces will be much cleaner Properties well-understood and

documented Requirements will be more mathematically

expressed

© 2006 Synopsys, Inc. (11)

Predictions for 2027• Fabrication technology (power, speed,

size, etc.), cost-effectiveness and feature set will continue to distinguish chips as they do today.

• Economics will continue to dominate the way electronics are designed and sold.

• Fab technology will often create new problems for mathematical analysis, e.g., verification under uncertainty of parts.

© 2006 Synopsys, Inc. (12)

HL Design – Huge Research Opportunities

• Model Checking at the word & transaction level

Increased capacity?

Better environmental information?

• Equivalence verification to RTL

• Leverage SW checking techniques

• Coverage opportunities

• ….

© 2006 Synopsys, Inc. (13)

Backup slides

© 2006 Synopsys, Inc. (14)

Puzzle • Fact 1: Verification accounts for 50% to

70% of the design resources (time, people, compute) on many chip projects.

• Fact 2: Verification tools make only a fraction of revenue compared with implementation tools (e.g., synthesis, place and route, DFM, etc.) in EDA. FORMAL verification tools (including logic

checking) make a VERY small fraction.

WHY?