In the last two parts of this series we’ve seen how to use GCC JIT and how to apply it to a simple regular expression matcher. But an open question remains, has it been worth the effort? This part will try to figure it out.
One of the quintessential UNIX tools is the grep tool. The global regular expression print is a tool that prints lines of text file that match a given regular expression. In this post we will apply JIT compilation to a very simple regular expression matcher by Rob Pike.
A just-in-time (JIT) compiler is a compiler that in contrast to the usual compilers is not run ahead-of-time, i.e. before running the actual program, but during the program itself.