Constraint Based Transformation Theory

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Constraint Based Transformation Theory

• Stefan Natelberg
• 2006-11-02

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Overview

• Why introduce a Constraint Based Transformation
  System?
• Key Points
• Benefits for SML
• Current FermaT Transformation
• Constraint Based FermaT Transformation
• Constraint Based Transformation Sequence
• Constraint Based Transformation Language
• Optimisation Example
• Restriction Example
• Future Work

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Why Introduce a Constraint Based Transformation
System?

• Customise the transformations to meet different
  requirements
• Simplify the use of transformation sequences

4
Key points

• Extend the FermaT Engine with Constraint Based
  Transformations
• Define Constraint Based Transformation Sequences
• Develop a priority system for constraints
• Invent a Constraint Based Transformation Language
  (CBTL)
• Develop a framework for integration and testing
  of new constraints

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Benefits for SML

• Control a transformation process via constraints
• Get very quick results to compare different
  solutions of a problem
• Eliminate some critical elements like pointer
  automatically
• Customise migrated code to meet different needs

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Current FermaT Transformation
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Constraint Based FermaT Transformation
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Constraint Based Transformation Sequence
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Constraint Based Transformation Language (CBTL)

• Controls the entire transformation process
• Define legacy system elements as objects
• Consider constraints as optimisation or
  restriction for an object during the
  transformation process
• Supports a priority system for constraints

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Optimisation ExampleAssembler Code
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Optimisation ExampleAssembler Code translated
to WSL
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Optimisation ExampleTransformed WSL Code
Constraint Least Lines of Code
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Optimisation ExampleTransformed WSL Code
translated to C
Constraint Least Lines of Code
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Optimisation ExampleTransformed WSL Code
Constraint Structured Code
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Optimisation ExampleTransformed WSL Code
translated to C
Constraint Structured Code
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Optimisation ExampleTransformed WSL Code
Constraint Efficient Code
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Optimisation ExampleTransformed WSL Code
translated to C
Constraint Efficient Code
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Optimisation ExampleCompare Code translated to C
Least Lines of Code
Structured Code
Efficient Code
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Optimisation ExampleCompare Code translated to C
Least Lines of Code
Structured Code
Efficient Code
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Restriction Example

• Object pointer
• new Object
• s_var,
• s_lbracket,
• s_expression,
• s_rbracket
• eliminate(pointer)
• reduce(pointer)

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Restriction Example

• Object pointer
• new Object
• s_var,
• s_lbracket,
• s_expression,
• s_rbracket
• eliminate(pointer)
• reduce(pointer)

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Restriction Example

• Object pointer
• new Object
• s_var,
• s_lbracket,
• s_expression,
• s_rbracket
• eliminate(pointer)
• reduce(pointer)

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Future Work

• Within the next 3 Month
• Finish the literature review
• Start to develop the CBT Framework
• Define new constraints
• Write the first constraint based transformations
• Within the next 6 Month
• Write the transfer report
• Write the first constraint based transformation
  sequences
• Start to develop the script language

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Thank you for your questions!