The US Department of Energy has released nearly 50 proxy applications (http://proxyapps.exascaleproject.org/). These are simplified applications that represent key characteristics of a wide class of scientific computing workloads. We've conducted in-depth performance analysis of Clang-generated code for these proxy applications, comparing to GCC-compiled code and, in some cases, code generated by vendor compilers, and have found some interesting places where Clang could do better. In this talk, we'll walk through several interesting examples and present some data on overall trends which, in some cases, are surprising.
