Minimal Compilers

Recently, I did an experiment by switching on only a fast and simple RA and combiner in GCC. There are no options to do this, I needed to modify GCC. (I can provide a patch if somebody is interested.) Compared to hundreds of optimizations in GCC-9.0 with -O2, these two optimizations achieve almost 80% performance on an Intel i7-9700K machine under Fedora Core 29 for real-world programs through SpecCPU, one of the most credible compiler benchmark suites - Vladimir Makarov behind MIR This project aims to get 70% of LLVM / GCC perf from 10% of the code. That’s probably easy on average. There are a lot of things in LLVM that give a huge perf win for a tiny subset of inputs. If you care about the performance of something that hits one of these on its most critical path, you will see a huge difference. If you care about aggregate performance over a large corpus, very few of these makes a very significant overall difference. - david_chisnall LLVM does NOT provide full C compatibility for…