tr-announce

Download

tr-announce@lists.rwth-aachen.de

September 2005

1 participants
2 discussions

2005-19: Tangent-Linear Models by Augmented LL-Parsers
by Volker Stolz 09 Sep '05

09 Sep '05

The following technical report is available from http://aib.informatik.rwth-aachen.de: Tangent-Linear Models by Augmented LL-Parsers Uwe Naumann, Andre Vehreschild AIB 2005-19 We describe a novel method for the generation of tangent-linear code by augmentation of LL-parsers generated by the software tool ANTLR. The main advantage of this approach to source code augmentation is the missing requirement for an internal representation of the original program. We consider this work as the basis for further investigations into how far this technique can be extended in the context of more sophisticated transformations, for example, the automatic generation of adjoint codes. Our prototype tool AD_C_ANTLR currently accepts a subset of the ANSI C standard. We discuss its theoretical basis, and we present case studies to underline the elegance of the parser-based approach to source augmentation.

1 0

2005-17: Syntax-directed Derivative Code (Part II: Intraprocedural Adjoint Code)
by Volker Stolz 06 Sep '05

06 Sep '05

The following technical report is available from http://aib.informatik.rwth-aachen.de: Syntax-directed Derivative Code (Part II: Intraprocedural Adjoint Code) Uwe Naumann AIB 2005-17 This is the second instance in a series of papers on single-pass generation of derivative codes by syntax-directed translation. We consider the automatic generation of adjoint code by reverse mode automatic differentiation implemented as the bottom-up propagation of synthesized attributes on the abstract syntax tree. A proof-of-concept implementation is presented based on a simple LALR(1) parser generated by the parser generator bison. The approach offers all advantages of adjoint codes while exhibiting the highly desirable ease of implementation.

1 0