1/20 principles of program analysis charngki hong @ pswlab principles of program analysis flemming...

1/20 Principles of Program Analysis Charngki Hong @ PSWLAB

Principles of Program Analysis

Flemming Nielson, Hanne Riis Nielson and Chris Hankin

2/20 Principles of Program Analysis Charngki Hong @ PSWLAB

Table of Contents

Introduction Data flow analysis Future work

Constraints based analysis References

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Introduction

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Table of Contents

Introduction Data flow analysis Future work

Constraints based analysis References

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Data flow analysis

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Data flow analysiselementary block :1. assignment state-

ment2. test statement3. skip statement

with labels

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Data flow analysis

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Reaching definitions analysis (1)

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Reaching definitions analysis (2)

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Reaching definitions analysis

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The best solution

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A safe solution – but not the best

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An unsafe solution

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How to automate the analysis

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Flow through assignments and tests

Var = { x, y, z }

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Flow along the control

Var = { x, y, z }

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Summary of equation system

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How to solve the equations

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The example equations

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Why does it work? (1)

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Why does it work? (2)

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Why does it work? (3)

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Future work Constraints based analysis

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Table of Contents

Introduction Data flow analysis Future work

Constraints based analysis References

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References Principles of program analysis, Flemming Niel-

son, Hanne Riis Nielson, Chris Hankin http://www2.imm.dtu.dk/~riis/PPA/ppa-

sup2004.html