On Libraries, Reuse, and the Value of EDA Software

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On Libraries, Reuse, and the Value of EDA
Software

• Igor MarkovUniv. of Michigan Synplicity

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Outline

• The challenge
• Extrapolating from past experiences
• What undermines the value of SW?
• What can we do ?

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The Challenge

• Are EDA companies undervalued ?
• Very sophisticated software
• Highly educated employees
• But stock does not grow !
• Little is said about creating value in EDA
  software development process
• Are we spinning our wheels ?
• Are we undermining the value of EDA ?
• Are there deficiencies in our eco-system?

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Efficiency, Success, Adoption

• How fast should EDA toolsbe developed ?
• Should they be maintained or rewritten ?
• How to ensure thatthey do their job well ?
• How to ensure/evaluate adoption?
• How to improve value of EDA tools?

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Personal Experiences

• Developing several academic tools adopted in
  companies
• UCLApack ? UMpack
• Capo, MLPart, infrastructure, etc
• Very liberal license
• Interaction with adopters
• We get 2-3 requests per week
• Measurements of popularityin academia
  (surprising conclusions)

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UCLApack / UMpack

• Developed mostly at UCLAby Andrew
  Caldwell(?Simplex ? Cadence ? Tabula)and Igor
  Markov (?U.Michigan)
• supervised by Andrew Kahng
• Initial release at DAC 2000
• 120K lines in C
• Currently over 200K lines

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Whats Available in UMpack?(1)

• Most popular the Capo placer
• Originally written in 1997-2000,maintained and
  extended at Michigan
• Uses min-cut partitioning, works well for lt100K
  std. cells
• Routability-driven(beats most of the academic
  tools, some commercial tools)
• Robust, well-tested, gt100 tape-outs
• All source code is available

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Whats Available in UMpack?(2)

• UCLA DB (written in 1998-1999)
• An object-oriented databasethat maps most of
  LEF/DEF syntaxto in-memory data structures
• Includes two parsers(one written at UCLA, one
  released by Cadence)
• Highly modular, reasonably efficient
• Not entirely up-to-date, but all sourceis
  available

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Whats Available in UMpack?(3)

• MLPart (written in 1997-2000)
• A multi-level min-cut partitioner
• Used in Capo ? has been tested extremely well
• Used by several companiesfor prototyping logic
  synthesis tools,for verification (production
  code)
• Results are usually a little worsethan hMetis,
  but MLPart is available in source code

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Whats Available in UMpack?(4)

• Parquet floorplanner (written in 2001-2004)
• Now a component of Capo
• Helped Capo outperform Cadence by 70 at ISPD
  2002
• Extensive infrastructurein two dozen packages
• Generic data structures, statistics
• Built-in debugging tools
• Geometry primitives, hierarchy mgmt, etc
• Utilities, e.g., LEFDEF ? our formats

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Whats Available in UMpack?(5)

• OpenAccess compatibility
• Michigan Cadence Labs
• UMpack/Capo is recommended for all OA Gear
  downloads
• Used to visualize circuits
• MLPart is compatible with hMetis
• C-API (Synplicity) hMetis wrapper
• Works with g 3.1 and above on Linux Solaris
• Works with MSVC on Windows
• Synplicity contribd a 64-bit port

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Whats Available in UMpack?(5)

• Simplified data formats
• The Capo input format is now supported by 20
  academic placers
• Intel, IBM and others have converters LEF/DEF
  converter
• A good number of examplesgiven as regression
  tests
• Documentation
• Web-based included self-documented code

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Adoption of Our Tools (1)

• The license allows any use for free(the MIT X
  Window license)
• No restrictions for academic use
• No notification requirement
• Dozens of papers reportmodifying Capo
• Start-ups asked for a list of people who know
  Capo source code

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Adoption of Our Tools (2)

• Synplicity used Capo in Amplify RC for LSI
  LogicRapid-chip architecture
• 100s tape-outs over two years
• Suddenly discontinued when LSI quit the fab
  business
• Several start-ups are still using Capo(are
  sending bug reports)
• MLPart is used in Certify

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Observations

• Surprise Capo adoption 10x greaterthan MLPart
  adoption
• MLPart has only one competitor(hMetis,
  unavailable in source code,unavailable for
  commercial use)
• There are about 10 academic placersclaim better
  results than Capo on large netlists (but none are
  available in source code)
• UCLA DB adoption non-existent
• Parquet adoption - huge

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Explanations ?

• Source-code availability does wonders
• EDA industry EDA researchis tool-oriented
• To force people think about infrastructure, we
  need the scale of OpenAccess
• A good library can be overlookedb/c its value is
  not clearly seen
• Best combination lightweight toolwith a clear
  functionality

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Personal Experiences

• Superficial familiarity with commercial EDA
  software
• Talking to developers
• Listening to invited talks
• Occasionally looking at source code
• 8 EDA companies, names starting with
• A, C, I, M, S

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EDA Industry SW is Old

• Several companies limitg to very old versions
• Perceived stability
• At least 20 lost in tool runtime
• Old versions may not support many language
  features
• Several companies ban C
• Main argument developers shoot themselves in
  the foot

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Compare to UCLApack

• Written with heavy use of C
• Relies on the Standard Template Library (STL) for
  data structures
• Abundant online documentation
• Undergraduate students know it(vs. homegrown
  data structuresin companies)
• Very efficient
• Clean and elegant interface
• UCLApack practically no pointers

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Compare to UCLApack

• Use of STL ?
• More compact, conceptual code
• Less documentation
• Less unit testing
• However
• Using STL was a nightmarebefore 2002
• Now g and MSVC are stable

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Takeaways

• To improve productivity
• Must use C with STL
• Must develop reusablesoftware libraries with
  clean interfaces
• (as is done by OpenAccess coalition)
• Obstacles?
• Maturity level of SW developers

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Personal Experiences (3)

• Coaching Michigan students participating in ICCAD
  CADathlon
• Three wins for Michigan in 5-6 years
• Two 2nd places
• Participating in ISPD contests
• Won the routing contest last year
• Where did the best coders go?(are they still
  interested in EDA ?)

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Observations

• Of CADathlon prize-winners
• One went to Microsoft, one to LM
• Two quit EDA
• One became an EDA faculty
• Two are working for EDA companies
• Big questions
• Do we need to attract best coders?
• Is there much room improving SW?

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ISPD PR contests

• Dramatic year-to-year improvements in results
• In 2006 and 2007, the 1st place team was last the
  year before !
• In most cases, the winning entries were written
  from scratch(APlace, Kraftwerk2, MaizeRoute,
  FGR)
• Academic tools better than industry

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Efficiency, Success, Adoption

• How fast should EDA toolsbe developed ?
• Should they be maintained or rewritten ?
• How to ensure thatthey do their job well ?
• Is EDA research at fault ?
• How to improve value of EDA tools?

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Conclusions

• Existing EDA code-basesare old and inefficient
• Rely on outdated SW development infrastructure
• There is room for improvementin core tools new
  tools are needed
• Need to ensure better code reuse
• New SW development methods more efficient
• Need to attract best codersand keep them

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Riddle for you

• The greatest threatto the EDA industry
• Six letters _ _ _ _ _ _Letters T