Talk: Symbolic Analysis for the VFC Compiler

Symbolic Analysis for the VFC Compiler.
Seminar on Code Optimisation: Trends, Challenges and Perspectives,
Schloß Dagstuhl, Germany

The quality of many optimizations and analyses for parallelizing compilers significantly depends on the ability to evaluate symbolic expressions and on the amount of information available about program variables at arbitrary program points. We describe an effective and unified symbolic evaluation framework that statically determines the values of variables and symbolic expressions, assumptions about and constraints between variable values and the condition under which control flow reaches a program statement. The framework computes program contexts at arbitrary program points, which are a novel representation for comprehensive and compact control and data flow analysis information. All of our techniques target both linear and non-linear expressions and constraints. The efficiency of symbolic analysis is highly improved by aggressive simplification techniques. To illustrate the effectiveness of our approach we present an example for communication vectorization.