Dynamic Program Analysis

1
Dynamic Program Analysis
Motivation for writing specs Instant
gratification

• Klaus Havelund
• Kestrel Technology
• NASA Ames Research Center

2
Static and Dynamic Analysis
?
Specification
Test case generation
Runtime verification
Program
Input
Output
Program instrumentation
3
Of course it is not Ideal
Property language power
IDEAL
Scalability
Coverage
4
Runtime Verification

• Specification-based monitoring
• Algorithm-based monitoring
• For test
• For fault protection

5
Specification-Based monitoring.Problem is to
choose a specification language

• Pre/post conditions, invariants
• Eiffel, JML, Javas assert.
• Temporal logic Temporal Rover, MAC
• Real-time properties Timed Automata
• Quantified temporal logic SipmaFinkbeiner
• Statecharts TLChart
• Process algebra Jass
• Regular expressions Rosu, MAC
• Wide spectrum Spec, VDM
• Embed in for example RWL LTL in Maude (JPAX)
• Combining logics into one notation MAC, TLChart,
  Eagle

6
Eagle

• Three temporal connectives
• Next _at_F
• Previous F
• Concatenation F1F2
• Recursive parameterized rules over trace
  Even(Term t) t \/ _at_Even(t) .
• Ktimes(int k, Term t)
• kgt0 -gt (t /\ Ktimes(t-1,t)) .

7
Algorithm-Based monitoring.Problem is to
classify errors

• Memory leaks
• Purify.
• Low level data races and deadlocks Visual
  Threads, JProbe, JPAX.
• High level data races
• Stoller, Flanagan, JPAX.

8
Program InstrumentationProblem is reducing
overhead

• Aspect Oriented Programming AspectJ, AspectC,
  AspectC, MOP
• Object code/byte code instr.
• Java BCEL, Jtrek, jContractor, jMonitor
• Others Valgrind

9
But Properties are Hard to Formulate

• To quote quite excellent NASA software
• engineer when asked what properties his
• system would have to satisfy
• I have absolutely no! idea what properties
• this system should satisfy.

10
Specification Generation

• Inferring invariants
• DAIKON
• Inferring temporal properties
• Yang Evans

11
Static and Dynamic Analysis

• Static analysis can reduce
• instrumentation overhead.
• Dynamic analysis functions as fall
• back position for properties that cannot
• be proven statically.

12
Two Recently CreatedWorkshop Series

• RV
• Workshop On Runtime Verification
• http//react.cs.uni-sb.de/rv2005
• WODA
• Workshop On Dynamic Analysis
• http//www.csd.uwo.ca/woda2005