126 lines
4.0 KiB
Prolog
126 lines
4.0 KiB
Prolog
/*************************************************************************
|
|
* *
|
|
* YAP Prolog *
|
|
* *
|
|
* Yap Prolog was developed at NCCUP - Universidade do Porto *
|
|
* *
|
|
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
|
|
* *
|
|
**************************************************************************
|
|
* *
|
|
* File: eval.yap *
|
|
* Last rev: *
|
|
* mods: *
|
|
* comments: optimise disjunction handling *
|
|
* *
|
|
*************************************************************************/
|
|
|
|
:- system_module( '$_eval', [], ['$full_clause_optimisation'/4]).
|
|
|
|
:- use_system_module( terms, [new_variables_in_term/3,
|
|
variables_within_term/3]).
|
|
|
|
|
|
%, portray_clause((H:-BF))
|
|
'$full_clause_optimisation'(H, M, B0, BF) :-
|
|
'$localise_vars_opt'(H, M, B0, BF), !.
|
|
|
|
% the idea here is to make global variables in disjunctions
|
|
% local.
|
|
'$localise_vars_opt'(H, M, (B1;B2), (NB1;NB2)) :-
|
|
'$variables_in_term'(H, [], LV),
|
|
'$localise_vars'(B1, M, NB1, LV, LV, []),
|
|
'$localise_disj_vars'(B2, M, NB2, LV, LV, []).
|
|
|
|
'$localise_disj_vars'((B;B2), M, (NB ; NB2), LV, LV0, LEqs) :- !,
|
|
'$localise_vars'(B, M, NB, LV, LV0, LEqs),
|
|
'$localise_disj_vars'(B2, M, NB2, LV, LV0, LEqs).
|
|
'$localise_disj_vars'(B2, M, NB, LV, LV0, LEqs) :-
|
|
'$localise_vars'(B2, M, NB, LV, LV0, LEqs).
|
|
|
|
'$localise_vars'((A->B), M, (A->NB), LV, LV0, LEqs) :-
|
|
'$safe_guard'(A, M), !,
|
|
'$variables_in_term'(A, LV, LV1),
|
|
'$localise_vars'(B, M, NB, LV1, LV0, LEqs).
|
|
'$localise_vars'((A;B), M, (NA;NB), LV1, LV0, LEqs) :- !,
|
|
'$localise_vars'(A, M, NA, LV1, LV0, LEqs),
|
|
'$localise_disj_vars'(B, M, NB, LV1, LV0, LEqs).
|
|
'$localise_vars'(((A,B),C), M, NG, LV, LV0, LEqs) :- !,
|
|
'$flatten_bd'((A,B),C,NB),
|
|
'$localise_vars'(NB, M, NG, LV, LV0, LEqs).
|
|
'$localise_vars'((!,B), M, (!,NB), LV, LV0, LEqs) :- !,
|
|
'$localise_vars'(B, M, NB, LV, LV0, LEqs).
|
|
'$localise_vars'((X=Y,B), M, (X=Y,NB1), LV, LV0, LEqs) :-
|
|
var(X), var(Y), !,
|
|
'$localise_vars'(B, M, NB1, LV, LV0, [X,Y|LEqs]).
|
|
'$localise_vars'((G,B), M, (G,NB1), LV, LV0, LEqs) :-
|
|
'$safe_builtin'(G, M), !,
|
|
'$variables_in_term'(G, LV, LV1),
|
|
'$add_extra_safe'(G, NLV0, LV0),
|
|
'$localise_vars'(B, M, NB1, LV1, NLV0, LEqs).
|
|
'$localise_vars'((G1,B1), _, O, LV, LV0, LEqs) :- !,
|
|
terms:variables_within_term(LV, B1, Commons),
|
|
terms:new_variables_in_term(LV, B1, New),
|
|
copy_term(Commons+New+LEqs+B1, NCommons+NNew+NLEqs+NB1),
|
|
NNew = New,
|
|
NLEqs = LEqs,
|
|
'$gen_equals'(Commons, NCommons, LV0, (G1,NB1), O).
|
|
'$localise_vars'(G, _, G, _, _, _).
|
|
|
|
'$gen_equals'([], [], _, O, O).
|
|
'$gen_equals'([V|Commons],[NV|NCommons], LV0, O, NO) :- V == NV, !,
|
|
'$gen_equals'(Commons,NCommons, LV0, O, NO).
|
|
'$gen_equals'([V|Commons],[NV|NCommons], LV0, O, OO) :-
|
|
'$vmember'(V,LV0),
|
|
OO = (V=NV,'$safe'(NV),NO),
|
|
'$gen_equals'(Commons,NCommons, LV0, O, NO).
|
|
'$gen_equals'([V|Commons],[NV|NCommons], LV0, O, OO) :-
|
|
OO = (V=NV,NO),
|
|
'$gen_equals'(Commons,NCommons, LV0, O, NO).
|
|
|
|
'$safe_guard'((A,B), M) :- !,
|
|
'$safe_guard'(A, M),
|
|
'$safe_guard'(B, M).
|
|
'$safe_guard'((A;B), M) :- !,
|
|
'$safe_guard'(A, M),
|
|
'$safe_guard'(B, M).
|
|
'$safe_guard'(A, M) :- !,
|
|
'$safe_builtin'(A, M).
|
|
|
|
'$safe_builtin'(G, Mod) :-
|
|
'$predicate_flags'(G, Mod, Fl, Fl),
|
|
Fl /\ 0x00008880 =\= 0.
|
|
|
|
'$vmember'(V,[V1|_]) :- V == V1, !.
|
|
'$vmember'(V,[_|LV0]) :-
|
|
'$vmember'(V,LV0).
|
|
|
|
'$flatten_bd'((A,B),R,NB) :- !,
|
|
'$flatten_bd'(B,R,R1),
|
|
'$flatten_bd'(A,R1,NB).
|
|
'$flatten_bd'(A,R,(A,R)).
|
|
|
|
'$add_extra_safe'('$plus'(_,_,V)) --> !, [V].
|
|
'$add_extra_safe'('$minus'(_,_,V)) --> !, [V].
|
|
'$add_extra_safe'('$times'(_,_,V)) --> !, [V].
|
|
'$add_extra_safe'('$div'(_,_,V)) --> !, [V].
|
|
'$add_extra_safe'('$and'(_,_,V)) --> !, [V].
|
|
'$add_extra_safe'('$or'(_,_,V)) --> !, [V].
|
|
'$add_extra_safe'('$sll'(_,_,V)) --> !, [V].
|
|
'$add_extra_safe'('$slr'(_,_,V)) --> !, [V].
|
|
'$add_extra_safe'(C=D,A,B) :-
|
|
!,
|
|
( compound(C) ->
|
|
'$variables_in_term'(C,E,A)
|
|
;
|
|
E=A
|
|
),
|
|
( compound(D) ->
|
|
'$variables_in_term'(D,B,E)
|
|
;
|
|
B=E
|
|
).
|
|
'$add_extra_safe'(_) --> [].
|
|
|
|
|