Andrew MacLeod wrote:
A new register allocator written from scratch is a very long term project (measured in years), and there is no guarantee after all that work that we'd end up with something which is remarkably better. One would hope that it is a lot more maintainable, but the generated code is a crapshot. It will surely look better but will it really run faster? The current plate of spaghetti we call the register allocator has had a lot of fine tuning go into it over the years, and it generally generates pretty darn good code IF it doesn't have to spill much, which is much of the time.
If you are starting from scratch would it not be better to adopt the approach of combining register allocation and scheduling. Significant progress has been made in this area in recent years.
