On Thu 20 Mar 2014 11:06, Marco Maggi <marco.maggi-i...@poste.it> writes:
> Something similar can be done for return values[1]; in > Vicare every function call site has 2 return points: one for > single return value; the other for 0, 2, more return values. > One return point goes on with the computation, the other > raises an exception. > > [1] Ashley and Dybvig. "An Efficient Implementation of > Multiple Return Values in Scheme". Proceedings of the 1994 > ACM Conference on Lisp and Functional Programming, 140-149, > Orlando, June 1994. Incidentally I think this is not such a nice approach -- multiple-value returns kill the return-branch buffer. I suspect this is a very 1994 strategy. For example, it's common to call a function and discard its arguments. This is trivial with a single return location. With MV you miss the return-branch buffer and you still play jump games. The single-value return is also very easy -- just check the number-of-return-values register (or, if values are on the stack, check the stack pointer) and branch to error if you didn't get the right number. Branch prediction helps here. Andy -- http://wingolog.org/
