Irregexp supports allowing jitcode to find all matches for a given regexp in an input string, instead of just the first match. This is currently inactive in the irregexp port, and is enabled by the attached patch. This is a nice improvement for global regexp execution. If I repeatedly run the /\d+/g regexp times on an 8kb string with a mix of digits and characters then using global mode is 20%-40% faster than repeatedly finding single matches. Unfortunately though this doesn't really impact benchmark scores. So maybe it's a good idea to land this (otherwise we should remove the global stuff entirely) but I think this can wait until yarr is entirely gone, which will simplify the code a lot.