bool TermVarSearchProp(Term_p term, DerefType deref, TermProperties prop)
{
PStack_p stack = PStackAlloc();
int i;
bool res = false;
PStackPushP(stack, term);
PStackPushInt(stack, deref);
while(!PStackEmpty(stack))
{
deref = PStackPopInt(stack);
term = PStackPopP(stack);
term = TermDeref(term, &deref);
if(TermIsVar(term) && TermCellQueryProp(term, prop))
{
res = true;
break;
}
for(i=0; i<term->arity; i++)
{
PStackPushP(stack, term->args[i]);
PStackPushInt(stack, deref);
}
}
PStackFree(stack);
return res;
}
Term_p VarBankFCodeAssertAlloc(VarBank_p bank, FunCode f_code)
{
Term_p var;
assert(f_code < 0);
var = VarBankFCodeFind(bank, f_code);
if(!var)
{
var = TermDefaultCellAlloc();
var->entry_no = f_code;
var->f_code = f_code;
TermCellSetProp(var, TPIsShared);
PDArrayAssignP(bank->f_code_index, -f_code, var);
bank->max_var = MAX(-f_code, bank->max_var);
}
assert(!TermCellQueryProp(var, TPIsGround));
return var;
}
Term_p term_top_marked(Term_p term, VarBank_p freshvars, PStack_p
bindings)
{
Term_p handle;
if(TermCellQueryProp(term, TPOpFlag))
{
if(!term->binding)
{
handle = VarBankGetFreshVar(freshvars);
term->binding = handle;
PStackPushP(bindings, term);
}
else
{
handle = term->binding;
}
}
else if(TermIsVar(term))
{
handle = VarBankFCodeAssertAlloc(freshvars, term->f_code);
}
else
{
handle = TermDefaultCellAlloc();
handle->arity = term->arity;
handle->f_code = term->f_code;
if(handle->arity > 0)
{
int i;
handle->args = TermArgArrayAlloc(handle->arity);
for(i=0; i<handle->arity; i++)
{
handle->args[i] = term_top_marked(term->args[i],
freshvars, bindings);
}
}
}
return handle;
}
void TermFree(Term_p junk)
{
assert(junk);
if(!TermIsVar(junk))
{
assert(!TermCellQueryProp(junk, TPIsShared));
if(junk->arity)
{
int i;
assert(junk->args);
for(i=0; i<junk->arity; i++)
{
TermFree(junk->args[i]);
}
}
else
{
assert(!junk->args);
}
TermTopFree(junk);
}
}
static void pdtree_forward(PDTree_p tree, Subst_p subst)
{
PDTNode_p handle = tree->tree_pos, next = NULL;
FunCode i = tree->tree_pos->trav_count, limit;
Term_p term = PStackTopP(tree->term_stack);
limit = PDT_NODE_CLOSED(tree,handle);
while(i<limit)
{
if(((i==0)||(i>handle->max_var))&&!TermIsVar(term))
{
next = IntMapGetVal(handle->f_alternatives,term->f_code);
i++;
if(next)
{
PStackPushP(tree->term_proc, term);
TermLRTraverseNext(tree->term_stack);
next->trav_count = PDT_NODE_INIT_VAL(tree);
next->bound = false;
assert(!next->variable);
tree->tree_pos = next;
#ifdef MEASURE_EXPENSIVE
tree->visited_count++;
#endif
break;
}
}
else
{
next = PDArrayElementP(handle->v_alternatives,i);
i++;
if(next)
{
assert(next->variable);
if((!next->variable->binding)&&(!TermCellQueryProp(term,TPPredPos)))
{
PStackDiscardTop(tree->term_stack);
SubstAddBinding(subst, next->variable, term);
next->trav_count = PDT_NODE_INIT_VAL(tree);
next->bound = true;
tree->tree_pos = next;
tree->term_weight -= (TermStandardWeight(term) -
TermStandardWeight(next->variable));
#ifdef MEASURE_EXPENSIVE
tree->visited_count++;
#endif
break;
}
else if(TBTermEqual(next->variable->binding,term))
{
PStackDiscardTop(tree->term_stack);
next->trav_count = PDT_NODE_INIT_VAL(tree);
next->bound = false;
tree->tree_pos = next;
tree->term_weight -= (TermStandardWeight(term) -
TermStandardWeight(next->variable));
#ifdef MEASURE_EXPENSIVE
tree->visited_count++;
#endif
break;
}
}
}
}
handle->trav_count = i;
}
