Introducing ‘nocoalias’ attribute to improve context-sensitive alias analysis in LLVM

Abstract

The technique of alias analysis enables us to determine which memory locations can be accessed via different access paths. But finding objects satisfying aliasing sets is hard. We present a context-sensitive approach to improve alias analysis. In this compile-time approach, we check for aliasing between various function arguments at the call-site and propagate this information by means of an attribute to the function definition. This allows the optimizer to obtain better information about the function parameters, and hence open opportunities for various optimizations in the function definition itself.