Termination and shape-shifting heaps

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Termination and shape-shifting heaps

Byron Cook bycook_at_microsoft.com
Microsoft Research, Cambridge Joint work with
Josh Berdine, Dino Distefano, and Peter
OHearn
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Experimental results with Terminator
CAV06,PLDI06,SAS05
Lines of code (x1000)
Cut-point set size
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Experimental results with Terminator
CAV06,PLDI06,SAS05
Lines of code (x1000)
Cut-point set size
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Experimental results with Terminator
CAV06,PLDI06,SAS05
Lines of code (x1000)
Cut-point set size
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Experimental results with Terminator
CAV06,PLDI06,SAS05
Lines of code (x1000)
Cut-point set size
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Experimental results with Terminator
CAV06,PLDI06,SAS05
Lines of code (x1000)
Cut-point set size
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Outline

• Introduction
• TERMINATORs proof rule
• MUTANT/TERMINATOR
• Experimental results
• Conclusion Discussion

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Outline

• Introduction
• TERMINATORs proof rule
• MUTANT/TERMINATOR
• Experimental results
• Conclusion Discussion

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TERMINATORs proof rule
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TERMINATORs proof rule
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TERMINATORs proof rule
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TERMINATORs proof rule
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TERMINATORs proof rule
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TERMINATORs proof rule
Ø
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TERMINATORs proof rule
Ø
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TERMINATORs proof rule
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TERMINATORs proof rule
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TERMINATORs proof rule
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TERMINATORs proof rule
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TERMINATORs proof rule
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TERMINATORs proof rule
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TERMINATORs proof rule
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TERMINATORs proof rule
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Outline

• Introduction
• TERMINATORs proof rule
• MUTANT/TERMINATOR
• Experimental results
• Conclusion Discussion

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Outline

• Introduction
• TERMINATORs proof rule
• MUTANT/TERMINATOR
• Experimental results
• Conclusion Discussion

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Reversing the strategy
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Reversing the strategy
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Reversing the strategy
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Reversing the strategy
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Reversing the strategy
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Reversing the strategy
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Mutant
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Mutant
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Mutant example
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Mutant example
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Mutant example
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Mutant example
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Mutant example
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Mutant example
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Outline

• Introduction
• TERMINATORs proof rule
• MUTANT/TERMINATOR
• Experimental results
• Conclusion Discussion

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Outline

• Introduction
• TERMINATORs proof rule
• MUTANT/TERMINATOR
• Experimental results
• Conclusion Discussion

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Experimental results

• Revisiting loops falsely accused with TERMINATOR

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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Introduction
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Outline

• Introduction
• TERMINATORs proof rule
• MUTANT/TERMINATOR
• Experimental results
• Conclusion Discussion

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Outline

• Introduction
• TERMINATORs proof rule
• MUTANT/TERMINATOR
• Experimental results
• Conclusion Discussion

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Conclusion Discussion

• Constructing automatic termination provers out of
  abstract interpreters
• Over-approximate binary reachability using
  encoding into states
• Prove each state (partitioning of
  over-approximation) well-founded
• MUTANT/TERMINATOR
• Application using separation logic based abstract
  interpretation

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Conclusion Discussion

• Whats next combining termination analysis
  engines
• Integer linear programs (TERMINATOR, roughly
  speaking)
• Mutating heaps (MUTANT)
• Non-linear programs (ZIGZAG)

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Conclusion Discussion

• Whats next combining termination analysis
  engines
• Integer linear programs (TERMINATOR, roughly
  speaking)
• Mutating heaps (MUTANT)
• Non-linear programs (ZIGZAG)

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Conclusion Discussion

• Whats next combining termination analysis
  engines
• Integer linear programs (TERMINATOR, roughly
  speaking)
• Mutating heaps (MUTANT)
• Non-linear programs (ZIGZAG)

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Conclusion Discussion

• Whats next combining termination analysis
  engines
• Integer linear programs (TERMINATOR, roughly
  speaking)
• Mutating heaps (MUTANT)
• Non-linear programs (ZIGZAG)

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Conclusion Discussion

• See http//research.microsoft.com/TERMINATOR
• Not-quite-camera-ready copy of CAV06 paper about
  MUTANT
• Papers about TERMINATOR (PLDI06, SAS06, CAV06)
• Questions?