Prolog to WAM Register Allocation?

Hello all,


      I'm currently studying how Prolog compiles its source into Warren
Abstract Machine code and I was wondering what kind of algorithm does
Prolog use to assign variables and constants to X and Y registers?


For instance, predicate(X,Y,john) allocates X1 for X, X2 for Y, and X3
for john ? or, when I pass a query ?- lives_in(john, X) Do I assume
that X variable is bound value is in X1 or X2?


I've seen numerous literature on code generation/register allocation
for imperative languages (on register-based machines and stack-based
machines) but there seems to be no literature at all on how Prolog code
generation against Warren Abstract machines (Ait-Kaci's book barely
touches on this subject). Any idea on where such information could be
found?


Thanks!

Return to the comp.compilers page.
Search the comp.compilers archives again.