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yap-6.3/C/utilpreds.c
Vitor Santos Costa 2d65d0463c jupyter
2019-02-27 04:23:21 +00:00

3071 lines
67 KiB
C

/*************************************************************************
* *
* YAP Prolog *
* *
* Yap Prolog was developed at NCCUP - Universidade do Porto *
* *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
* *
**************************************************************************
* *
* File: utilpreds.c * Last rev: 4/03/88
** mods: * comments: new utility predicates for YAP *
* *
*************************************************************************/
#ifdef SCCS
static char SccsId[] = "@(#)utilpreds.c 1.3";
#endif
/**
* @file utilpreds.c
*
* @addtogroup Terms
*/
#include "absmi.h"
#include "YapHeap.h"
#include "yapio.h"
#include "attvar.h"
#ifdef HAVE_STRING_H
#include "string.h"
#endif
typedef struct non_single_struct_t {
CELL *ptd0;
CELL d0;
CELL *pt0, *pt0_end;
} non_singletons_t;
#define def_trail_overflow() \
trail_overflow:{ \
while (to_visit > to_visit0) { \
to_visit --; \
CELL *ptd0 = to_visit->ptd0; \
*ptd0 = to_visit->d0; \
} \
pop_text_stack(lvl); \
LOCAL_Error_TYPE = RESOURCE_ERROR_TRAIL; \
LOCAL_Error_Size = (TR-TR0)*sizeof(tr_fr_ptr *); \
clean_tr(TR0 PASS_REGS); \
HR = InitialH; \
return 0L; \
}
#define def_aux_overflow() \
aux_overflow:{ \
size_t d1 = to_visit-to_visit0; \
size_t d2 = to_visit_max-to_visit0; \
to_visit0 = Realloc(to_visit0,(d2+128)*sizeof(struct non_single_struct_t)); \
to_visit = to_visit0+d1; \
to_visit_max = to_visit0+(d2+128); \
pt0--; \
goto restart; \
}
#define def_global_overflow() \
global_overflow:{ \
while (to_visit > to_visit0) { \
to_visit --; \
CELL *ptd0 = to_visit->ptd0; \
*ptd0 = to_visit->d0; \
} \
pop_text_stack(lvl); \
clean_tr(TR0 PASS_REGS); \
HR = InitialH; \
LOCAL_Error_TYPE = RESOURCE_ERROR_STACK; \
LOCAL_Error_Size = (ASP-HR)*sizeof(CELL); \
return false; }
static Int p_copy_term( USES_REGS1 );
#ifdef DEBUG
static Int p_force_trail_expansion( USES_REGS1 );
#endif /* DEBUG */
static inline void
clean_tr(tr_fr_ptr TR0 USES_REGS) {
if (TR != TR0) {
do {
Term p = TrailTerm(--TR);
RESET_VARIABLE(p);
} while (TR != TR0);
}
}
static inline void
clean_dirty_tr(tr_fr_ptr TR0 USES_REGS) {
tr_fr_ptr pt0 = TR;
while (pt0 != TR0) {
Term p = TrailTerm(--pt0);
if (IsApplTerm(p)) {
CELL *pt = RepAppl(p);
#ifdef FROZEN_STACKS
pt[0] = TrailVal(pt0);
#else
pt[0] = TrailTerm(pt0 - 1);
pt0 --;
#endif /* FROZEN_STACKS */
} else {
RESET_VARIABLE(p);
}
}
TR = TR0;
}
/// @brief recover original term while fixing direct refs.
///
/// @param USES_REGS
///
static inline void
clean_complex_tr(tr_fr_ptr TR0 USES_REGS) {
tr_fr_ptr pt0 = TR;
while (pt0 != TR0) {
Term p = TrailTerm(--pt0);
if (IsApplTerm(p)) {
/// pt: points to the address of the new term we may want to fix.
CELL *pt = RepAppl(p);
if (pt >= HB && pt < HR) { /// is it new?
Term v = pt[0];
if (IsApplTerm(v)) {
/// yes, more than a single ref
*pt = (CELL)RepAppl(v);
}
#ifndef FROZEN_STACKS
pt0 --;
#endif /* FROZEN_STACKS */
continue;
}
#ifdef FROZEN_STACKS
pt[0] = TrailVal(pt0);
#else
pt[0] = TrailTerm(pt0 - 1);
pt0 --;
#endif /* FROZEN_STACKS */
} else {
RESET_VARIABLE(p);
}
}
TR = TR0;
}
#define expand_stack(S0,SP,SF,TYPE) \
{ size_t sz = SF-S0, used = SP-S0; \
S0 = Realloc(S0, (1024+sz)*sizeof(TYPE) PASS_REGS); \
SP = S0+used; SF = S0+sz; }
#define MIN_ARENA_SIZE (1048L)
int Yap_copy_complex_term(register CELL *pt0, register CELL *pt0_end,
bool share, bool copy_att_vars, CELL *ptf,
CELL *HLow USES_REGS) {
// fprintf(stderr,"+++++++++\n");
//CELL *x = pt0; while(x != pt0_end) Yap_DebugPlWriteln(*++ x);
int lvl = push_text_stack();
struct cp_frame *to_visit0,
*to_visit = Malloc(1024*sizeof(struct cp_frame));
struct cp_frame *to_visit_max;
CELL *HB0 = HB;
tr_fr_ptr TR0 = TR;
int ground = true;
HB = HLow;
to_visit0 = to_visit;
to_visit_max = to_visit+1024;
loop:
while (pt0 < pt0_end) {
register CELL d0;
register CELL *ptd0;
ptd0 = ++pt0;
d0 = *ptd0;
deref:
deref_head(d0, copy_term_unk);
copy_term_nvar : {
if (IsPairTerm(d0)) {
CELL *headp = RepPair(d0);
if (//(share && headp < HB) ||
(IsPairTerm(*headp) && RepPair(*headp) >= HB && RepPair(*headp) < HR)) {
/* If this is newer than the current term, just reuse */
*ptf++ = *headp;
continue;
}
if (to_visit >= to_visit_max-32) {
expand_stack(to_visit0, to_visit, to_visit_max, struct cp_frame);
}
*ptf = AbsPair(HR);
ptf++;
to_visit->start_cp = pt0;
to_visit->end_cp = pt0_end;
to_visit->to = ptf;
to_visit->ground = ground;
to_visit++;
// move to new list
d0 = *headp;
TrailedMaBind(headp, AbsPair(HR));
pt0 = headp;
pt0_end = headp + 1;
ptf = HR;
ground = true;
HR += 2;
if (HR > ASP - MIN_ARENA_SIZE) {
goto overflow;
}
ptd0 = pt0;
goto deref;
} else if (IsApplTerm(d0)) {
register Functor f;
register CELL *headp;
/* store the terms to visit */
headp = RepAppl(d0);
if (IsApplTerm(*headp)//(share && headp < HB) ||
) {
/* If this is newer than the current term, just reuse */
*ptf++ = *headp;
continue;
}
f = (Functor)(*headp);
if (IsExtensionFunctor(f)) {
switch ((CELL)f) {
case (CELL) FunctorDBRef:
case (CELL) FunctorAttVar:
*ptf++ = d0;
break;
case (CELL) FunctorLongInt:
if (HR > ASP - (MIN_ARENA_SIZE + 3)) {
goto overflow;
}
*ptf++ = AbsAppl(HR);
HR[0] = (CELL)f;
HR[1] = headp[1];
HR[2] = EndSpecials;
HR += 3;
if (HR > ASP - MIN_ARENA_SIZE) {
goto overflow;
}
break;
case (CELL) FunctorDouble:
if (HR >
ASP - (MIN_ARENA_SIZE + (2 + SIZEOF_DOUBLE / sizeof(CELL)))) {
goto overflow;
}
*ptf++ = AbsAppl(HR);
HR[0] = (CELL)f;
HR[1] = headp[1];
#if SIZEOF_DOUBLE == 2 * SIZEOF_INT_P
HR[2] = headp[2];
HR[3] = EndSpecials;
HR += 4;
#else
HR[2] = EndSpecials;
HR += 3;
#endif
break;
case (CELL) FunctorString:
if (ASP - HR < MIN_ARENA_SIZE + 3 + headp[1]) {
goto overflow;
}
*ptf++ = AbsAppl(HR);
memmove(HR, headp, sizeof(CELL) * (3 + headp[1]));
HR += headp[1] + 3;
break;
default: {
/* big int */
size_t sz = (sizeof(MP_INT) + 3 * CellSize +
((MP_INT *)(headp + 2))->_mp_alloc * sizeof(mp_limb_t)) /
CellSize,
i;
if (HR > ASP - (MIN_ARENA_SIZE + sz)) {
goto overflow;
}
*ptf++ = AbsAppl(HR);
HR[0] = (CELL)f;
for (i = 1; i < sz; i++) {
HR[i] = headp[i];
}
HR += sz;
}
}
continue;
}
*ptf = AbsAppl(HR);
ptf++;
/* store the terms to visit */
to_visit->start_cp = pt0;
to_visit->end_cp = pt0_end;
to_visit->to = ptf;
to_visit->ground = ground;
if (++to_visit >= to_visit_max-32) {
expand_stack(to_visit0, to_visit, to_visit_max, struct cp_frame);
}
TrailedMaBind(headp,AbsAppl(HR));
ptf = HR;
*ptf++ = (CELL)f;
ground = true;
arity_t a = ArityOfFunctor(f);
HR = ptf+a;
if (HR > ASP - MIN_ARENA_SIZE) {
goto overflow;
}
pt0 = headp;
pt0_end = headp+a;
ground = (f != FunctorMutable);
} else {
/* just copy atoms or integers */
*ptf++ = d0;
}
continue;
}
derefa_body(d0, ptd0, copy_term_unk, copy_term_nvar);
ground = false;
/* don't need to copy variables if we want to share the global term */
if (//(share && ptd0 < HB && ptd0 > H0) ||
(ptd0 >= HLow && ptd0 < HR)) {
/* we have already found this cell */
*ptf++ = (CELL)ptd0;
} else {
if (copy_att_vars && GlobalIsAttachedTerm((CELL)ptd0)) {
/* if unbound, call the standard copy term routine */
struct cp_frame *bp;
CELL new;
bp = to_visit;
if (!GLOBAL_attas[ExtFromCell(ptd0)].copy_term_op(ptd0, &bp,
ptf PASS_REGS)) {
goto overflow;
}
to_visit = bp;
new = *ptf;
if (TR > (tr_fr_ptr)LOCAL_TrailTop - 256) {
/* Trail overflow */
if (!Yap_growtrail((TR - TR0) * sizeof(tr_fr_ptr *), TRUE)) {
goto trail_overflow;
}
}
TrailedMaBind(ptd0, new);
ptf++;
} else {
/* first time we met this term */
RESET_VARIABLE(ptf);
if ((ADDR)TR > LOCAL_TrailTop - MIN_ARENA_SIZE)
goto trail_overflow;
TrailedMaBind(ptd0, (CELL)ptf);
ptf++;
}
}
}
/* Do we still have compound terms to visit */
if (to_visit > to_visit0) {
to_visit--;
pt0 = to_visit->start_cp;
pt0_end = to_visit->end_cp;
ptf = to_visit->to;
ground = (ground && to_visit->ground);
goto loop;
}
/* restore our nice, friendly, term to its original state */
clean_dirty_tr(TR0 PASS_REGS);
/* follow chain of multi-assigned variables */
pop_text_stack(lvl);
return 0;
overflow:
/* oops, we're in trouble */
HR = HLow;
/* we've done it */
/* restore our nice, friendly, term to its original state */
HB = HB0;
while (to_visit > to_visit0) {
to_visit--;
pt0 = to_visit->start_cp;
pt0_end = to_visit->end_cp;
ptf = to_visit->to;
}
reset_trail(TR0);
pop_text_stack(lvl);
return -1;
trail_overflow:
/* oops, we're in trouble */
HR = HLow;
/* we've done it */
/* restore our nice, friendly, term to its original state */
HB = HB0;
while (to_visit > to_visit0) {
to_visit--;
pt0 = to_visit->start_cp;
pt0_end = to_visit->end_cp;
ptf = to_visit->to;
}
reset_trail(TR0);
pop_text_stack(lvl);
return -4;
}
static Term
handle_cp_overflow(int res, tr_fr_ptr TR0, UInt arity, Term t)
{
CACHE_REGS
XREGS[arity+1] = t;
switch(res) {
case -1:
if (!Yap_gcl((ASP-HR)*sizeof(CELL), arity+1, ENV, gc_P(P,CP))) {
Yap_Error(RESOURCE_ERROR_STACK, TermNil, LOCAL_ErrorMessage);
return 0L;
}
return Deref(XREGS[arity+1]);
case -2:
return Deref(XREGS[arity+1]);
case -3:
{
UInt size = LOCAL_Error_Size;
LOCAL_Error_Size = 0L;
if (size > 4*1024*1024)
size = 4*1024*1024;
if (!Yap_ExpandPreAllocCodeSpace(size, NULL, TRUE)) {
Yap_Error(RESOURCE_ERROR_AUXILIARY_STACK, TermNil, LOCAL_ErrorMessage);
return 0L;
}
}
return Deref(XREGS[arity+1]);
case -4:
if (!Yap_growtrail((TR-TR0)*sizeof(tr_fr_ptr *), FALSE)) {
Yap_Error(RESOURCE_ERROR_TRAIL, TermNil, LOCAL_ErrorMessage);
return 0L;
}
return Deref(XREGS[arity+1]);
default:
return 0L;
}
}
static Term
CopyTerm(Term inp, UInt arity, int share, int newattvs USES_REGS) {
Term t = Deref(inp);
tr_fr_ptr TR0 = TR;
CELL *Hi;
if (IsPrimitiveTerm(t)) {
return t;
}
while( true ) {
int res;
Hi = HR;
HR ++;
if ((res = Yap_copy_complex_term((&t)-1, &t, share, newattvs, Hi, HR PASS_REGS)) < 0) {
HR = Hi;
if ((t = handle_cp_overflow(res, TR0, arity, t))== 0L)
return FALSE;
} else if (res && share) {
HR = Hi;
return t;
}
return Hi[0];
}
return 0;
}
Term
Yap_CopyTerm(Term inp) {
CACHE_REGS
return CopyTerm(inp, 0, false, TRUE PASS_REGS);
}
Term
Yap_CopyTermNoShare(Term inp) {
CACHE_REGS
return CopyTerm(inp, 0, FALSE, FALSE PASS_REGS);
}
static Int
p_copy_term( USES_REGS1 ) /* copy term t to a new instance */
{
Term t = CopyTerm(ARG1, 2, false, TRUE PASS_REGS);
if (t == 0L)
return FALSE;
/* be careful, there may be a stack shift here */
return Yap_unify(ARG2,t);
}
static Int
p_duplicate_term( USES_REGS1 ) /* copy term t to a new instance */
{
Term t = CopyTerm(ARG1, 2, FALSE, TRUE PASS_REGS);
if (t == 0L)
return FALSE;
/* be careful, there may be a stack shift here */
return Yap_unify(ARG2,t);
}
static Int
p_copy_term_no_delays( USES_REGS1 ) /* copy term t to a new instance */
{
Term t = CopyTerm(ARG1, 2, TRUE, FALSE PASS_REGS);
if (t == 0L) {
return FALSE;
}
/* be careful, there may be a stack shift here */
return(Yap_unify(ARG2,t));
}
typedef struct bp_frame {
CELL *start_cp;
CELL *end_cp;
CELL *to;
CELL *oldp;
CELL oldv;
} bp_frame_t;
typedef struct copy_frame {
CELL *start_cp;
CELL *end_cp;
CELL *to;
} copy_frame_t;
/*
FAST EXPORT ROUTINE. Export a Prolog term to something like:
CELL 0: offset for start of term
CELL 1: size of actual term (to be copied to stack)
CELL 2: the original term (just for reference)
Atoms and functors:
- atoms are either:
0 and a char *string
-1 and a wchar_t *string
- functors are a CELL with arity and a string.
Compiled Term.
*/
static inline
CELL *CellDifH(CELL *hptr, CELL *hlow)
{
return (CELL *)((char *)hptr-(char *)hlow);
}
#define AdjustSizeAtom(X) (((CELL)(X)+(8-1)) & ~(8-1))
static inline
CELL *AdjustSize(CELL *x, char *buf)
{
UInt offset = (char *)x-buf;
return (CELL*)(buf+AdjustSizeAtom(offset));
}
/* export an atom from the symbol table to a buffer */
static inline
Atom export_atom(Atom at, char **hpp, char *buf, size_t len)
{
char *ptr, *p0;
size_t sz;
ptr = *hpp;
ptr = (char *)AdjustSize((CELL*)ptr, buf);
p0 = ptr;
*ptr++ = 0;
sz = strlen(RepAtom(at)->StrOfAE);
if (sz + 1 >= len)
return (Atom)NULL;
strcpy(ptr, RepAtom(at)->StrOfAE);
*hpp = ptr+(sz+1);
return (Atom)(p0-buf);
}
/* place a buffer: first arity then the atom */
static inline
Functor export_functor(Functor f, char **hpp, char *buf, size_t len)
{
CELL *hptr = AdjustSize((CELL *)*hpp, buf);
UInt arity = ArityOfFunctor(f);
if (2*sizeof(CELL) >= len)
return NULL;
hptr[0] = arity;
*hpp = (char *)(hptr+1);
if (!export_atom(NameOfFunctor(f), hpp, buf, len))
return NULL;
/* increment so that it cannot be mistaken with a functor on the stack,
(increment is used as a tag ........01
*/
return (Functor)(((char *)hptr-buf)+1);
}
#define export_derefa_body(D,A,LabelUnk,LabelNonVar) \
do { \
if ((CELL *)(D) < CellDifH(HR,HLow)) { (A) = (CELL *)(D); break; } \
(A) = (CELL *)(D); \
(D) = *(CELL *)(D); \
if(!IsVarTerm(D)) goto LabelNonVar; \
LabelUnk: ; \
} while (Unsigned(A) != (D))
static int
export_term_to_buffer(Term inpt, char *buf, char *bptr, CELL *t0 , CELL *tf, size_t len)
{
char *td = bptr;
CELL *bf = (CELL *)buf;
if (buf + len < (char *)((CELL *)td + (tf-t0))) {
return FALSE;
}
memmove((void *)td, (void *)t0, (tf-t0)* sizeof(CELL));
bf[0] = (td-buf);
bf[1] = (tf-t0);
bf[2] = inpt;
return bf[0]+sizeof(CELL)*bf[1];
}
static size_t
export_complex_term(Term tf, CELL *pt0, CELL *pt0_end, char * buf, size_t len0, int newattvs, CELL *ptf, CELL *HLow USES_REGS)
{
struct cp_frame *to_visit0, *to_visit = (struct cp_frame *)Yap_PreAllocCodeSpace();
CELL *HB0 = HB;
tr_fr_ptr TR0 = TR;
int ground = TRUE;
char *bptr = buf+ 3*sizeof(CELL);
size_t len = len0;
HB = HLow;
to_visit0 = to_visit;
loop:
while (pt0 < pt0_end) {
register CELL d0;
register CELL *ptd0;
++ pt0;
ptd0 = pt0;
d0 = *ptd0;
deref_head(d0, export_term_unk);
export_term_nvar:
{
if (IsPairTerm(d0)) {
CELL *ap2 = RepPair(d0);
if (ap2 < CellDifH(HR,HLow)) {
/* If this is newer than the current term, just reuse */
*ptf++ = d0;
continue;
}
*ptf = AbsPair(CellDifH(HR,HLow));
ptf++;
#ifdef RATIONAL_TREES
if (to_visit+1 >= (struct cp_frame *)AuxSp) {
goto heap_overflow;
}
to_visit->start_cp = pt0;
to_visit->end_cp = pt0_end;
to_visit->to = ptf;
to_visit->oldv = *pt0;
to_visit->ground = ground;
/* fool the system into thinking we had a variable there */
*pt0 = AbsPair(CellDifH(HR,HLow));
to_visit ++;
#else
if (pt0 < pt0_end) {
if (to_visit+1 >= (struct cp_frame *)AuxSp) {
goto heap_overflow;
}
to_visit->start_cp = pt0;
to_visit->end_cp = pt0_end;
to_visit->to = ptf;
to_visit->ground = ground;
to_visit ++;
}
#endif
pt0 = ap2 - 1;
pt0_end = ap2 + 1;
ptf = HR;
HR += 2;
if (HR > ASP - 2048) {
goto overflow;
}
} else if (IsApplTerm(d0)) {
register Functor f;
register CELL *ap2;
/* store the terms to visit */
ap2 = RepAppl(d0);
if (ap2 < CellDifH(HR,HLow)) {
/* If this is newer than the current term, just reuse */
*ptf++ = d0;
continue;
}
f = (Functor)(*ap2);
*ptf++ = AbsAppl(CellDifH(HR,HLow));
if (IsExtensionFunctor(f)) {
UInt sz;
/* make sure to export floats */
if (f== FunctorDouble) {
sz = sizeof(Float)/sizeof(CELL)+2;
} else if (f== FunctorLongInt) {
sz = 3;
} else if (f== FunctorString) {
sz = 3+ap2[1];
} else {
CELL *pt = ap2+1;
sz = 2+sizeof(MP_INT)+(((MP_INT *)(pt+1))->_mp_alloc*sizeof(mp_limb_t));
}
if (HR+sz > ASP - 2048) {
goto overflow;
}
memmove((void *)HR, (void *)ap2, sz*sizeof(CELL));
HR += sz;
continue;
}
/* store the terms to visit */
#ifdef RATIONAL_TREES
if (to_visit+1 >= (struct cp_frame *)AuxSp) {
goto heap_overflow;
}
to_visit->start_cp = pt0;
to_visit->end_cp = pt0_end;
to_visit->to = ptf;
to_visit->oldv = *pt0;
to_visit->ground = ground;
/* fool the system into thinking we had a variable there */
*pt0 = AbsAppl(HR);
to_visit ++;
#else
if (pt0 < pt0_end) {
if (to_visit+1 >= (struct cp_frame *)AuxSp) {
goto heap_overflow;
}
to_visit->start_cp = pt0;
to_visit->end_cp = pt0_end;
to_visit->to = ptf;
to_visit->ground = ground;
to_visit ++;
}
#endif
ground = (f != FunctorMutable);
d0 = ArityOfFunctor(f);
pt0 = ap2;
pt0_end = ap2 + d0;
/* store the functor for the new term */
ptf = HR+1;
HR += 1+d0;
if (HR > ASP - 2048) {
goto overflow;
}
ptf[-1] = (CELL)export_functor(f, &bptr, buf, len);
len = len0 - (bptr-buf);
if (HR > ASP - 2048) {
goto overflow;
}
} else {
if (IsAtomTerm(d0)) {
*ptf = MkAtomTerm(export_atom(AtomOfTerm(d0), &bptr, buf, len));
ptf++;
len = len0 - (bptr-buf);
} else {
*ptf++ = d0;
}
}
continue;
}
export_derefa_body(d0, ptd0, export_term_unk, export_term_nvar);
ground = FALSE;
if (ptd0 < CellDifH(HR,HLow)) {
/* we have already found this cell */
*ptf++ = (CELL) ptd0;
} else {
#if COROUTINING
if (newattvs && IsAttachedTerm((CELL)ptd0) && FALSE) {
/* if unbound, call the standard export term routine */
struct cp_frame *bp;
CELL new;
bp = to_visit;
if (!GLOBAL_attas[ExtFromCell(ptd0)].copy_term_op(ptd0, &bp, ptf PASS_REGS)) {
goto overflow;
}
to_visit = bp;
new = *ptf;
Bind_NonAtt(ptd0, new);
ptf++;
} else {
#endif
/* first time we met this term */
*ptf = (CELL)CellDifH(ptf,HLow);
if (TR > (tr_fr_ptr)LOCAL_TrailTop - 256) {
/* Trail overflow */
if (!Yap_growtrail((TR-TR0)*sizeof(tr_fr_ptr *), TRUE)) {
goto trail_overflow;
}
}
Bind_NonAtt(ptd0, (CELL)ptf);
ptf++;
#ifdef COROUTINING
}
#endif
}
}
/* Do we still have compound terms to visit */
if (to_visit > to_visit0) {
to_visit --;
pt0 = to_visit->start_cp;
pt0_end = to_visit->end_cp;
ptf = to_visit->to;
#ifdef RATIONAL_TREES
*pt0 = to_visit->oldv;
#endif
ground = (ground && to_visit->ground);
goto loop;
}
/* restore our nice, friendly, term to its original state */
clean_dirty_tr(TR0 PASS_REGS);
HB = HB0;
return export_term_to_buffer(tf, buf, bptr, HLow, HR, len0);
overflow:
/* oops, we're in trouble */
HR = HLow;
/* we've done it */
/* restore our nice, friendly, term to its original state */
HB = HB0;
#ifdef RATIONAL_TREES
while (to_visit > to_visit0) {
to_visit --;
pt0 = to_visit->start_cp;
pt0_end = to_visit->end_cp;
ptf = to_visit->to;
*pt0 = to_visit->oldv;
}
#endif
reset_trail(TR0);
/* follow chain of multi-assigned variables */
return -1;
trail_overflow:
/* oops, we're in trouble */
HR = HLow;
/* we've done it */
/* restore our nice, friendly, term to its original state */
HB = HB0;
#ifdef RATIONAL_TREES
while (to_visit > to_visit0) {
to_visit --;
pt0 = to_visit->start_cp;
pt0_end = to_visit->end_cp;
ptf = to_visit->to;
*pt0 = to_visit->oldv;
}
#endif
{
tr_fr_ptr oTR = TR;
reset_trail(TR0);
if (!Yap_growtrail((oTR-TR0)*sizeof(tr_fr_ptr *), TRUE)) {
return -4;
}
return -2;
}
heap_overflow:
/* oops, we're in trouble */
HR = HLow;
/* we've done it */
/* restore our nice, friendly, term to its original state */
HB = HB0;
#ifdef RATIONAL_TREES
while (to_visit > to_visit0) {
to_visit --;
pt0 = to_visit->start_cp;
pt0_end = to_visit->end_cp;
ptf = to_visit->to;
*pt0 = to_visit->oldv;
}
#endif
reset_trail(TR0);
LOCAL_Error_Size = (ADDR)AuxSp-(ADDR)to_visit0;
return -3;
}
static size_t
ExportTerm(Term inp, char * buf, size_t len, UInt arity, int newattvs USES_REGS) {
Term t = Deref(inp);
tr_fr_ptr TR0 = TR;
size_t res = 0;
CELL *Hi = HR;
do {
if (IsVarTerm(t) || IsIntTerm(t)) {
return export_term_to_buffer(t, buf, buf+ 3*sizeof(CELL), &inp, &inp, len);
}
if (IsAtomTerm(t)) {
Atom at = AtomOfTerm(t);
char *b = buf+3*sizeof(CELL);
export_atom(at, &b, b, len-3*sizeof(CELL));
return export_term_to_buffer(t, buf, b, &inp, &inp, len);
}
if ((Int)res < 0) {
HR = Hi;
TR = TR0;
if ((t = handle_cp_overflow(res, TR0, arity, t))== 0L)
return res;
}
Hi = HR;
TR0 = TR;
res = export_complex_term(inp, &t-1, &t, buf, len, newattvs, Hi, Hi PASS_REGS);
} while ((Int)res < 0);
return res;
}
size_t
Yap_ExportTerm(Term inp, char * buf, size_t len, UInt arity) {
CACHE_REGS
return ExportTerm(inp, buf, len, arity, TRUE PASS_REGS);
}
static CELL *
ShiftPtr(CELL t, char *base)
{
return (CELL *)(base+t);
}
static Atom
addAtom(Atom t, char *buf)
{
char *s = buf+(UInt)t;
if (!*s) {
return Yap_LookupAtom(s+1);
}
return NULL;
}
static UInt
FetchFunctor(CELL *pt, char *buf)
{
CELL *ptr = (CELL *)(buf+(*pt-1));
// do arity first
UInt arity = *ptr++;
Atom name, at;
// and then an atom
ptr = AdjustSize(ptr, buf);
name = (Atom)((char *)ptr-buf);
at = addAtom(name, buf);
*pt = (CELL)Yap_MkFunctor(at, arity);
return arity;
}
static CELL *import_compound(CELL *hp, char *abase, char *buf, CELL *amax);
static CELL *import_pair(CELL *hp, char *abase, char *buf, CELL *amax);
static CELL *
import_arg(CELL *hp, char *abase, char *buf, CELL *amax)
{
Term t = *hp;
if (IsVarTerm(t)) {
hp[0] = (CELL)ShiftPtr(t, abase);
} else if (IsAtomTerm(t)) {
hp[0] = MkAtomTerm(addAtom(AtomOfTerm(t), buf));
} else if (IsPairTerm(t)) {
CELL *newp = ShiftPtr((CELL)RepPair(t), abase);
hp[0] = AbsPair(newp);
if (newp > amax) {
amax = import_pair(newp, abase, buf, newp);
}
} else if (IsApplTerm(t)) {
CELL *newp = ShiftPtr((CELL)RepAppl(t), abase);
hp[0] = AbsAppl(newp);
if (newp > amax) {
amax = import_compound(newp, abase, buf, newp);
}
}
return amax;
}
static CELL *
import_compound(CELL *hp, char *abase, char *buf, CELL *amax)
{
Functor f = (Functor)*hp;
UInt ar, i;
if (!((CELL)f & 1) && IsExtensionFunctor(f))
return amax;
ar = FetchFunctor(hp, buf);
for (i=1; i<=ar; i++) {
amax = import_arg(hp+i, abase, buf, amax);
}
return amax;
}
static CELL *
import_pair(CELL *hp, char *abase, char *buf, CELL *amax)
{
amax = import_arg(hp, abase, buf, amax);
amax = import_arg(hp+1, abase, buf, amax);
return amax;
}
Term
Yap_ImportTerm(char * buf) {
CACHE_REGS
CELL *bc = (CELL *)buf;
size_t sz = bc[1];
Term tinp, tret;
tinp = bc[2];
if (IsVarTerm(tinp))
return MkVarTerm();
else if (IsIntTerm(tinp))
return tinp;
else if (IsAtomTerm(tinp)) {
tret = MkAtomTerm(addAtom(NULL,(char *)(bc+3)));
return tret;
}
// call the gc/stack shifter mechanism
// if not enough stack available
while (HR + sz > ASP - 4096) {
if (!Yap_gcl( (sz+4096)*sizeof(CELL), PP->ArityOfPE, ENV, gc_P(P,CP))) {
Yap_Error(RESOURCE_ERROR_STACK, TermNil, LOCAL_ErrorMessage);
return 0L;
}
}
memmove(HR, buf+bc[0], sizeof(CELL)*sz);
if (IsApplTerm(tinp)) {
tret = AbsAppl(HR);
import_compound(HR, (char *)HR, buf, HR);
} else {
tret = AbsPair(HR);
import_pair(HR, (char *)HR, buf, HR);
}
HR += sz;
return tret;
}
size_t
Yap_SizeOfExportedTerm(char * buf) {
CELL *bc = (CELL *)buf;
return bc[0]+bc[1]*sizeof(CELL);
}
static Int
p_export_term( USES_REGS1 )
{
size_t sz = 4096, osz;
char *export_buf;
do {
export_buf = malloc(sz);
if (!export_buf)
return FALSE;
if (!(osz = Yap_ExportTerm(ARG1, export_buf, sz, 1))) {
sz += 4096;
free(export_buf);
}
} while (!osz);
return Yap_unify(ARG3,MkIntegerTerm(osz)) &&
Yap_unify(ARG2, MkIntegerTerm((Int)export_buf));
}
static Int
p_import_term( USES_REGS1 )
{
char *export_buf = (char *)IntegerOfTerm(Deref(ARG1));
if (!export_buf)
return FALSE;
Int out = Yap_unify(ARG2,Yap_ImportTerm(export_buf));
return out;
}
static Int
p_kill_exported_term( USES_REGS1 )
{
char *export_buf = (char *)IntegerOfTerm(Deref(ARG1));
if (!export_buf)
return FALSE;
free(export_buf);
return TRUE;
}
static int
SizeOfExtension(Term t)
{
Functor f = FunctorOfTerm(t);
if (f== FunctorDouble) {
return 2 + sizeof(Float)/sizeof(CELL);
}
if (f== FunctorString) {
return 3 + RepAppl(t)[1];
}
if (f== FunctorLongInt) {
return 2 + sizeof(Float)/sizeof(CELL);
}
if (f== FunctorDBRef) {
return 0;
}
if (f== FunctorBigInt) {
CELL *pt = RepAppl(t)+2;
return 3+sizeof(MP_INT)+(((MP_INT *)(pt))->_mp_alloc*sizeof(mp_limb_t));
}
return 0;
}
static Int sz_ground_complex_term(register CELL *pt0, register CELL *pt0_end, int ground USES_REGS)
{
register CELL **to_visit0, **to_visit = (CELL **)Yap_PreAllocCodeSpace();
Int sz = 0;
to_visit0 = to_visit;
loop:
while (pt0 < pt0_end) {
register CELL d0;
register CELL *ptd0;
++pt0;
ptd0 = pt0;
d0 = *ptd0;
deref_head(d0, vars_in_term_unk);
vars_in_term_nvar:
{
if (IsPairTerm(d0)) {
sz += 2;
if (to_visit + 1024 >= (CELL **)AuxSp) {
goto aux_overflow;
}
#ifdef RATIONAL_TREES
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = (CELL *)*pt0;
to_visit += 3;
*pt0 = TermNil;
#else
if (pt0 < pt0_end) {
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit += 2;
}
#endif
pt0 = RepPair(d0) - 1;
pt0_end = RepPair(d0) + 1;
} else if (IsApplTerm(d0)) {
register Functor f;
register CELL *ap2;
/* store the terms to visit */
ap2 = RepAppl(d0);
f = (Functor)(*ap2);
if (IsExtensionFunctor(f)) {
sz += SizeOfExtension(d0);
continue;
}
if (to_visit + 1024 >= (CELL **)AuxSp) {
goto aux_overflow;
}
#ifdef RATIONAL_TREES
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = (CELL *)*pt0;
to_visit += 3;
*pt0 = TermNil;
#else
/* store the terms to visit */
if (pt0 < pt0_end) {
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit += 2;
}
#endif
d0 = ArityOfFunctor(f);
sz += (1+d0);
pt0 = ap2;
pt0_end = ap2 + d0;
}
continue;
}
derefa_body(d0, ptd0, vars_in_term_unk, vars_in_term_nvar);
if (!ground)
continue;
#ifdef RATIONAL_TREES
while (to_visit > to_visit0) {
to_visit -= 3;
pt0 = to_visit[0];
pt0_end = to_visit[1];
*pt0 = (CELL)to_visit[2];
}
#endif
return 0;
}
/* Do we still have compound terms to visit */
if (to_visit > to_visit0) {
#ifdef RATIONAL_TREES
to_visit -= 3;
pt0 = to_visit[0];
pt0_end = to_visit[1];
*pt0 = (CELL)to_visit[2];
#else
to_visit -= 2;
pt0 = to_visit[0];
pt0_end = to_visit[1];
#endif
goto loop;
}
return sz;
aux_overflow:
/* unwind stack */
#ifdef RATIONAL_TREES
while (to_visit > to_visit0) {
to_visit -= 3;
pt0 = to_visit[0];
*pt0 = (CELL)to_visit[2];
}
#endif
return -1;
}
int
Yap_SizeGroundTerm(Term t, int ground)
{
CACHE_REGS
if (IsVarTerm(t)) {
if (!ground)
return 1;
return 0;
} else if (IsPrimitiveTerm(t)) {
return 1;
} else if (IsPairTerm(t)) {
int sz = sz_ground_complex_term(RepPair(t)-1, RepPair(t)+1, ground PASS_REGS);
if (sz <= 0)
return sz;
return sz+2;
} else {
int sz = 0;
Functor fun = FunctorOfTerm(t);
if (IsExtensionFunctor(fun))
return 1+ SizeOfExtension(t);
sz = sz_ground_complex_term(RepAppl(t),
RepAppl(t)+
ArityOfFunctor(fun),
ground PASS_REGS);
if (sz <= 0)
return sz;
return 1+ArityOfFunctor(fun)+sz;
}
}
/* The code for TermHash was originally contributed by Gertjen Van Noor */
/* This code with max_depth == -1 will loop for infinite trees */
//-----------------------------------------------------------------------------
// MurmurHash2, by Austin Appleby
// Note - This code makes a few assumptions about how your machine behaves -
// 1. We can read a 4-byte value from any address without crashing
// 2. sizeof(int) == 4
// And it has a few limitations -
// 1. It will not work incrementally.
// 2. It will not produce the same results on litle-endian and big-endian
// machines.
static unsigned int
MurmurHashNeutral2 ( const void * key, int len, unsigned int seed )
{
const unsigned int m = 0x5bd1e995;
const int r = 24;
unsigned int h = seed ^ len;
const unsigned char * data = (const unsigned char *)key;
while(len >= 4)
{
unsigned int k;
k = data[0];
k |= data[1] << 8;
k |= data[2] << 16;
k |= data[3] << 24;
k *= m;
k ^= k >> r;
k *= m;
h *= m;
h ^= k;
data += 4;
len -= 4;
}
switch(len)
{
case 3: h ^= data[2] << 16;
case 2: h ^= data[1] << 8;
case 1: h ^= data[0];
h *= m;
};
h ^= h >> 13;
h *= m;
h ^= h >> 15;
return h;
}
static CELL *
addAtomToHash(CELL *st, Atom at)
{
unsigned int len;
char *c = RepAtom(at)->StrOfAE;
int ulen = strlen(c);
/* fix hashing over empty atom */
if (!ulen) {
return st;
}
if (ulen % CellSize == 0) {
len = ulen/CellSize;
} else {
len = ulen/CellSize;
len++;
}
st[len-1] = 0L;
strncpy((char *)st, c, ulen);
return st+len;
}
typedef struct visited {
CELL *start;
CELL *end;
CELL old;
UInt vdepth;
} visited_t;
static CELL *
hash_complex_term(register CELL *pt0,
register CELL *pt0_end,
Int depth,
CELL *st,
int variant USES_REGS)
{
register visited_t *to_visit0, *to_visit = (visited_t *)Yap_PreAllocCodeSpace();
to_visit0 = to_visit;
loop:
while (pt0 < pt0_end) {
register CELL d0;
register CELL *ptd0;
++ pt0;
ptd0 = pt0;
d0 = *ptd0;
deref_head(d0, hash_complex_unk);
hash_complex_nvar:
{
if (st + 1024 >= ASP) {
goto global_overflow;
}
if (IsAtomOrIntTerm(d0)) {
if (d0 != TermFoundVar) {
if (IsAtomTerm(d0)) {
st = addAtomToHash(st, AtomOfTerm(d0));
} else {
*st++ = IntOfTerm(d0);
}
}
continue;
} else if (IsPairTerm(d0)) {
st = addAtomToHash(st, AtomDot);
if (depth == 1)
continue;
if (to_visit + 256 >= (visited_t *)AuxSp) {
goto aux_overflow;
}
to_visit->start = pt0;
to_visit->end = pt0_end;
to_visit->old = *pt0;
to_visit->vdepth = depth;
to_visit++;
depth--;
*pt0 = TermFoundVar;
pt0 = RepPair(d0) - 1;
pt0_end = RepPair(d0) + 1;
continue;
} else if (IsApplTerm(d0)) {
register Functor f;
register CELL *ap2;
/* store the terms to visit */
ap2 = RepAppl(d0);
f = (Functor)(*ap2);
if (IsExtensionFunctor(f)) {
CELL fc = (CELL)f;
switch(fc) {
case (CELL)FunctorDBRef:
*st++ = fc;
break;
case (CELL)FunctorLongInt:
*st++ = LongIntOfTerm(d0);
break;
case (CELL)FunctorString:
memmove(st, RepAppl(d0), (3+RepAppl(d0)[1])*sizeof(CELL));
st += 3+RepAppl(d0)[1];
break;
#ifdef USE_GMP
case (CELL)FunctorBigInt:
{
CELL *pt = RepAppl(d0);
Int sz =
sizeof(MP_INT)+1+
(((MP_INT *)(pt+2))->_mp_alloc*sizeof(mp_limb_t));
if (st + (1024 + sz/CellSize) >= ASP) {
goto global_overflow;
}
/* then the actual number */
memmove((void *)(st+1), (void *)(pt+1), sz);
st = st+sz/CellSize;
}
break;
#endif
case (CELL)FunctorDouble:
{
CELL *pt = RepAppl(d0);
*st++ = pt[1];
#if SIZEOF_DOUBLE == 2*SIZEOF_INT_P
*st++ = pt[2];
#endif
break;
}
}
continue;
}
st = addAtomToHash(st, NameOfFunctor(f));
if (depth == 1)
continue;
if (to_visit + 1024 >= (visited_t *)AuxSp) {
goto aux_overflow;
}
to_visit->start = pt0;
to_visit->end = pt0_end;
to_visit->old = *pt0;
to_visit->vdepth = depth;
to_visit++;
depth--;
*pt0 = TermFoundVar;
d0 = ArityOfFunctor(f);
pt0 = ap2;
pt0_end = ap2 + d0;
}
continue;
}
deref_body(d0, ptd0, hash_complex_unk, hash_complex_nvar);
if (!variant)
return NULL;
else
continue;
}
/* Do we still have compound terms to visit */
if (to_visit > to_visit0) {
to_visit--;
pt0 = to_visit->start;
pt0_end = to_visit->end;
*pt0 = to_visit->old;
depth = to_visit->vdepth;
goto loop;
}
return st;
aux_overflow:
/* unwind stack */
while (to_visit > to_visit0) {
to_visit --;
pt0 = to_visit->start;
*pt0 = to_visit->old;
}
return (CELL *)-1;
global_overflow:
/* unwind stack */
while (to_visit > to_visit0) {
to_visit --;
pt0 = to_visit->start;
*pt0 = to_visit->old;
}
return (CELL *) -2;
}
Int
Yap_TermHash(Term t, Int size, Int depth, int variant)
{
CACHE_REGS
unsigned int i1;
Term t1 = Deref(t);
while (TRUE) {
CELL *ar = hash_complex_term(&t1-1, &t1, depth, HR, FALSE PASS_REGS);
if (ar == (CELL *)-1) {
if (!Yap_ExpandPreAllocCodeSpace(0, NULL, TRUE)) {
Yap_Error(RESOURCE_ERROR_AUXILIARY_STACK, ARG1, "overflow in term_hash");
return FALSE;
}
t1 = Deref(ARG1);
} else if(ar == (CELL *)-2) {
if (!Yap_gcl((ASP-HR)*sizeof(CELL), 0, ENV, gc_P(P,CP))) {
Yap_Error(RESOURCE_ERROR_STACK, TermNil, "in term_hash");
return FALSE;
}
t1 = Deref(ARG1);
} else if (ar == NULL) {
return FALSE;
} else {
i1 = MurmurHashNeutral2((const void *)HR, CellSize*(ar-HR),0x1a3be34a);
break;
}
}
/* got the seed and hash from SWI-Prolog */
return i1 % size;
}
static Int
p_term_hash( USES_REGS1 )
{
unsigned int i1;
Term t1 = Deref(ARG1);
Term t2 = Deref(ARG2);
Term t3 = Deref(ARG3);
Term result;
Int size, depth;
if (IsVarTerm(t2)) {
Yap_Error(INSTANTIATION_ERROR,t2,"term_hash/4");
return(FALSE);
}
if (!IsIntegerTerm(t2)) {
Yap_Error(TYPE_ERROR_INTEGER,t2,"term_hash/4");
return(FALSE);
}
depth = IntegerOfTerm(t2);
if (depth == 0) {
if (IsVarTerm(t1)) return(TRUE);
return(Yap_unify(ARG4,MkIntTerm(0)));
}
if (IsVarTerm(t3)) {
Yap_Error(INSTANTIATION_ERROR,t3,"term_hash/4");
return(FALSE);
}
if (!IsIntegerTerm(t3)) {
Yap_Error(TYPE_ERROR_INTEGER,t3,"term_hash/4");
return(FALSE);
}
size = IntegerOfTerm(t3);
while (TRUE) {
CELL *ar = hash_complex_term(&t1-1, &t1, depth, HR, FALSE PASS_REGS);
if (ar == (CELL *)-1) {
if (!Yap_ExpandPreAllocCodeSpace(0, NULL, TRUE)) {
Yap_Error(RESOURCE_ERROR_AUXILIARY_STACK, ARG1, "overflow in term_hash");
return FALSE;
}
t1 = Deref(ARG1);
} else if(ar == (CELL *)-2) {
if (!Yap_gcl((ASP-HR)*sizeof(CELL), 4, ENV, gc_P(P,CP))) {
Yap_Error(RESOURCE_ERROR_STACK, TermNil, "in term_hash");
return FALSE;
}
t1 = Deref(ARG1);
} else if (ar == NULL) {
return FALSE;
} else {
i1 = MurmurHashNeutral2((const void *)HR, CellSize*(ar-HR),0x1a3be34a);
break;
}
}
/* got the seed and hash from SWI-Prolog */
result = MkIntegerTerm(i1 % size);
return Yap_unify(ARG4,result);
}
static Int
p_instantiated_term_hash( USES_REGS1 )
{
unsigned int i1;
Term t1 = Deref(ARG1);
Term t2 = Deref(ARG2);
Term t3 = Deref(ARG3);
Term result;
Int size, depth;
if (IsVarTerm(t2)) {
Yap_Error(INSTANTIATION_ERROR,t2,"term_hash/4");
return(FALSE);
}
if (!IsIntegerTerm(t2)) {
Yap_Error(TYPE_ERROR_INTEGER,t2,"term_hash/4");
return(FALSE);
}
depth = IntegerOfTerm(t2);
if (depth == 0) {
if (IsVarTerm(t1)) return(TRUE);
return(Yap_unify(ARG4,MkIntTerm(0)));
}
if (IsVarTerm(t3)) {
Yap_Error(INSTANTIATION_ERROR,t3,"term_hash/4");
return(FALSE);
}
if (!IsIntegerTerm(t3)) {
Yap_Error(TYPE_ERROR_INTEGER,t3,"term_hash/4");
return(FALSE);
}
size = IntegerOfTerm(t3);
while (TRUE) {
CELL *ar = hash_complex_term(&t1-1, &t1, depth, HR, TRUE PASS_REGS);
if (ar == (CELL *)-1) {
if (!Yap_ExpandPreAllocCodeSpace(0, NULL, TRUE)) {
Yap_Error(RESOURCE_ERROR_AUXILIARY_STACK, ARG1, "overflow in term_hash");
return FALSE;
}
t1 = Deref(ARG1);
} else if(ar == (CELL *)-2) {
if (!Yap_gcl((ASP-HR)*sizeof(CELL), 4, ENV, gc_P(P,CP))) {
Yap_Error(RESOURCE_ERROR_STACK, TermNil, "in term_hash");
return FALSE;
}
t1 = Deref(ARG1);
} else if (ar == NULL) {
return FALSE;
} else {
i1 = MurmurHashNeutral2((const void *)HR, CellSize*(ar-HR),0x1a3be34a);
break;
}
}
/* got the seed and hash from SWI-Prolog */
result = MkIntegerTerm(i1 % size);
return Yap_unify(ARG4,result);
}
static int variant_complex(register CELL *pt0, register CELL *pt0_end, register
CELL *pt1 USES_REGS)
{
tr_fr_ptr OLDTR = TR;
register CELL **to_visit = (CELL **)ASP;
/* make sure that unification always forces trailing */
HBREG = HR;
loop:
while (pt0 < pt0_end) {
register CELL d0, d1;
++ pt0;
++ pt1;
d0 = Derefa(pt0);
d1 = Derefa(pt1);
if (IsVarTerm(d0)) {
if (IsVarTerm(d1)) {
CELL *pt0 = VarOfTerm(d0);
CELL *pt1 = VarOfTerm(d1);
if (pt0 >= HBREG || pt1 >= HBREG) {
/* one of the variables has been found before */
if (VarOfTerm(d0)+1 == VarOfTerm(d1)) continue;
goto fail;
} else {
/* two new occurrences of the same variable */
Term n0 = MkVarTerm(), n1 = MkVarTerm();
Bind_Global(VarOfTerm(d0), n0);
Bind_Global(VarOfTerm(d1), n1);
}
continue;
} else {
goto fail;
}
} else if (IsVarTerm(d1)) {
goto fail;
} else {
if (d0 == d1) continue;
else if (IsAtomOrIntTerm(d0)) {
goto fail;
} else if (IsPairTerm(d0)) {
if (!IsPairTerm(d1)) {
goto fail;
}
#ifdef RATIONAL_TREES
/* now link the two structures so that no one else will */
/* come here */
to_visit -= 4;
if ((CELL *)to_visit < HR+1024)
goto out_of_stack;
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit[3] = (CELL *)*pt0;
*pt0 = d1;
#else
/* store the terms to visit */
if (pt0 < pt0_end) {
to_visit -= 3;
if ((CELL *)to_visit < HR+1024)
goto out_of_stack;
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
}
#endif
pt0 = RepPair(d0) - 1;
pt0_end = RepPair(d0) + 1;
pt1 = RepPair(d1) - 1;
continue;
} else if (IsApplTerm(d0)) {
register Functor f;
register CELL *ap2, *ap3;
if (!IsApplTerm(d1)) {
goto fail;
} else {
/* store the terms to visit */
Functor f2;
ap2 = RepAppl(d0);
ap3 = RepAppl(d1);
f = (Functor)(*ap2);
f2 = (Functor)(*ap3);
if (f != f2)
goto fail;
if (IsExtensionFunctor(f)) {
if (!unify_extension(f, d0, ap2, d1))
goto fail;
continue;
}
#ifdef RATIONAL_TREES
/* now link the two structures so that no one else will */
/* come here */
to_visit -= 4;
if ((CELL *)to_visit < HR+1024)
goto out_of_stack;
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit[3] = (CELL *)*pt0;
*pt0 = d1;
#else
/* store the terms to visit */
if (pt0 < pt0_end) {
to_visit -= 3;
if ((CELL *)to_visit < HR+1024)
goto out_of_stack;
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
}
#endif
d0 = ArityOfFunctor(f);
pt0 = ap2;
pt0_end = ap2 + d0;
pt1 = ap3;
continue;
}
}
}
}
/* Do we still have compound terms to visit */
if (to_visit < (CELL **)ASP) {
#ifdef RATIONAL_TREES
pt0 = to_visit[0];
pt0_end = to_visit[1];
pt1 = to_visit[2];
*pt0 = (CELL)to_visit[3];
to_visit += 4;
#else
pt0 = to_visit[0];
pt0_end = to_visit[1];
pt1 = to_visit[2];
to_visit += 3;
#endif
goto loop;
}
HR = HBREG;
/* untrail all bindings made by variant */
while (TR != (tr_fr_ptr)OLDTR) {
CELL *pt1 = (CELL *) TrailTerm(--TR);
RESET_VARIABLE(pt1);
}
HBREG = B->cp_h;
return TRUE;
out_of_stack:
HR = HBREG;
/* untrail all bindings made by variant */
#ifdef RATIONAL_TREES
while (to_visit < (CELL **)ASP) {
pt0 = to_visit[0];
pt0_end = to_visit[1];
pt1 = to_visit[2];
*pt0 = (CELL)to_visit[3];
to_visit += 4;
}
#endif
while (TR != (tr_fr_ptr)OLDTR) {
CELL *pt1 = (CELL *) TrailTerm(--TR);
RESET_VARIABLE(pt1);
}
HBREG = B->cp_h;
return -1;
fail:
/* failure */
HR = HBREG;
#ifdef RATIONAL_TREES
while (to_visit < (CELL **)ASP) {
pt0 = to_visit[0];
pt0_end = to_visit[1];
pt1 = to_visit[2];
*pt0 = (CELL)to_visit[3];
to_visit += 4;
}
#endif
/* untrail all bindings made by variant */
while (TR != (tr_fr_ptr)OLDTR) {
CELL *pt1 = (CELL *) TrailTerm(--TR);
RESET_VARIABLE(pt1);
}
HBREG = B->cp_h;
return FALSE;
}
static bool
is_variant(Term t1, Term t2, int parity USES_REGS)
{
int out;
if (t1 == t2)
return true;
if (IsVarTerm(t1)) {
if (IsVarTerm(t2))
return true;
return false;
} else if (IsVarTerm(t2))
return false;
if (IsAtomOrIntTerm(t1)) {
return(t1 == t2);
}
if (IsPairTerm(t1)) {
if (IsPairTerm(t2)) {
out = variant_complex(RepPair(t1)-1,
RepPair(t1)+1,
RepPair(t2)-1 PASS_REGS);
if (out < 0) goto error;
return out != 0;
}
else return false;
}
if (!IsApplTerm(t2)) {
return false;
} else {
Functor f1 = FunctorOfTerm(t1);
if (f1 != FunctorOfTerm(t2)) return(FALSE);
if (IsExtensionFunctor(f1)) {
return(unify_extension(f1, t1, RepAppl(t1), t2));
}
out = variant_complex(RepAppl(t1),
RepAppl(t1)+ArityOfFunctor(f1),
RepAppl(t2) PASS_REGS);
if (out < 0) goto error;
return out != 0;
}
error:
if (out == -1) {
if (!Yap_gcl((ASP-HR)*sizeof(CELL), parity, ENV, gc_P(P,CP))) {
Yap_Error(RESOURCE_ERROR_STACK, TermNil, "in variant");
return FALSE;
}
return is_variant(t1, t2, parity PASS_REGS);
}
return false;
}
bool
Yap_Variant(Term t1, Term t2)
{
CACHE_REGS
return is_variant(t1, t2, 0 PASS_REGS);
}
static Int
p_variant( USES_REGS1 ) /* variant terms t1 and t2 */
{
return is_variant(Deref(ARG1), Deref(ARG2), 2 PASS_REGS);
}
static int subsumes_complex(register CELL *pt0, register CELL *pt0_end, register
CELL *pt1 USES_REGS)
{
register CELL **to_visit = (CELL **)ASP;
tr_fr_ptr OLDTR = TR, new_tr;
UInt write_mode = TRUE;
HBREG = HR;
loop:
while (pt0 < pt0_end) {
register CELL d0, d1;
Int our_write_mode = write_mode;
++ pt0;
++ pt1;
/* this is a version of Derefa that checks whether we are trying to
do something evil */
{
CELL *npt0 = pt0;
restart_d0:
if (npt0 >= HBREG) {
our_write_mode = FALSE;
}
d0 = *npt0;
if (IsVarTerm(d0) &&
d0 != (CELL)npt0
) {
npt0 = (CELL *)d0;
goto restart_d0;
}
}
{
CELL *npt1 = pt1;
restart_d1:
d1 = *npt1;
if (IsVarTerm(d1)
&& d1 != (CELL)npt1
) {
/* never dereference through a variable from the left-side */
if (npt1 >= HBREG) {
goto fail;
} else {
npt1 = (CELL *)d1;
goto restart_d1;
}
}
}
if (IsVarTerm(d0)) {
if (our_write_mode) {
/* generate a new binding */
CELL *pt0 = VarOfTerm(d0);
Term new = MkVarTerm();
Bind_Global(pt0, new);
if (d0 != d1) { /* avoid loops */
Bind_Global(VarOfTerm(new), d1);
if (Yap_rational_tree_loop(VarOfTerm(new)-1,VarOfTerm(new),(CELL **)AuxSp,(CELL **)AuxBase))
goto fail;
}
} else {
if (d0 == d1) continue;
goto fail;
}
continue;
} else if (IsVarTerm(d1)) {
goto fail;
} else {
if (d0 == d1) continue;
else if (IsAtomOrIntTerm(d0)) {
goto fail;
} else if (IsPairTerm(d0)) {
if (!IsPairTerm(d1)) {
goto fail;
}
#ifdef RATIONAL_TREES
/* now link the two structures so that no one else will */
/* come here */
to_visit -= 5;
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit[3] = (CELL *)*pt0;
to_visit[4] = (CELL *)write_mode;
*pt0 = d1;
#else
/* store the terms to visit */
if (pt0 < pt0_end) {
to_visit -= 4;
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit[3] = (CELL *)write_mode;
}
#endif
write_mode = our_write_mode;
pt0 = RepPair(d0) - 1;
pt0_end = RepPair(d0) + 1;
pt1 = RepPair(d1) - 1;
continue;
} else if (IsApplTerm(d0)) {
register Functor f;
register CELL *ap2, *ap3;
if (!IsApplTerm(d1)) {
goto fail;
} else {
/* store the terms to visit */
Functor f2;
ap2 = RepAppl(d0);
ap3 = RepAppl(d1);
f = (Functor)(*ap2);
f2 = (Functor)(*ap3);
if (f != f2)
goto fail;
if (IsExtensionFunctor(f)) {
if (!unify_extension(f, d0, ap2, d1))
goto fail;
continue;
}
#ifdef RATIONAL_TREES
/* now link the two structures so that no one else will */
/* come here */
to_visit -= 5;
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit[3] = (CELL *)*pt0;
to_visit[4] = (CELL *)write_mode;
*pt0 = d1;
#else
/* store the terms to visit */
if (pt0 < pt0_end) {
to_visit -= 4;
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit[3] = (CELL *)write_mode;
}
#endif
write_mode = our_write_mode;
d0 = ArityOfFunctor(f);
pt0 = ap2;
pt0_end = ap2 + d0;
pt1 = ap3;
continue;
}
}
}
}
/* Do we still have compound terms to visit */
if (to_visit < (CELL **)ASP) {
#ifdef RATIONAL_TREES
pt0 = to_visit[0];
pt0_end = to_visit[1];
pt1 = to_visit[2];
*pt0 = (CELL)to_visit[3];
write_mode = (Int)to_visit[ 4];
to_visit += 5;
#else
pt0 = to_visit[0];
pt0_end = to_visit[1];
pt1 = to_visit[2];
write_mode = (UInt)to_visit[3];
to_visit += 4;
#endif
goto loop;
}
HR = HBREG;
/* get rid of intermediate variables */
new_tr = TR;
while (TR != OLDTR) {
/* cell we bound */
CELL *pt1 = (CELL *) TrailTerm(--TR);
/* cell we created */
CELL *npt1 = (CELL *)*pt1;
/* shorten the chain */
if (IsVarTerm(*pt1) && IsUnboundVar(pt1)) {
RESET_VARIABLE(pt1);
} else {
*pt1 = *npt1;
}
}
TR = new_tr;
HBREG = B->cp_h;
return TRUE;
fail:
HR = HBREG;
#ifdef RATIONAL_TREES
while (to_visit < (CELL **)ASP) {
pt0 = to_visit[0];
pt0_end = to_visit[1];
pt1 = to_visit[2];
*pt0 = (CELL)to_visit[3];
to_visit += 5;
}
#endif
/* untrail all bindings made by variant */
while (TR != (tr_fr_ptr)OLDTR) {
CELL *pt1 = (CELL *) TrailTerm(--TR);
RESET_VARIABLE(pt1);
}
HBREG = B->cp_h;
return FALSE;
}
static Int
p_subsumes( USES_REGS1 ) /* subsumes terms t1 and t2 */
{
Term t1 = Deref(ARG1);
Term t2 = Deref(ARG2);
if (t1 == t2)
return (TRUE);
if (IsVarTerm(t1)) {
YapBind(VarOfTerm(t1), t2);
if (Yap_rational_tree_loop(VarOfTerm(t1)-1,VarOfTerm(t1),(CELL **)AuxSp,(CELL **)AuxBase))
return FALSE;
return TRUE;
} else if (IsVarTerm(t2))
return(FALSE);
if (IsAtomOrIntTerm(t1)) {
return(t1 == t2);
}
if (IsPairTerm(t1)) {
if (IsPairTerm(t2)) {
return(subsumes_complex(RepPair(t1)-1,
RepPair(t1)+1,
RepPair(t2)-1 PASS_REGS));
}
else return (FALSE);
} else {
Functor f1;
if (!IsApplTerm(t2)) return(FALSE);
f1 = FunctorOfTerm(t1);
if (f1 != FunctorOfTerm(t2))
return(FALSE);
if (IsExtensionFunctor(f1)) {
return(unify_extension(f1, t1, RepAppl(t1), t2));
}
return(subsumes_complex(RepAppl(t1),
RepAppl(t1)+ArityOfFunctor(f1),
RepAppl(t2) PASS_REGS));
}
}
static int term_subsumer_complex(register CELL *pt0, register CELL *pt0_end, register
CELL *pt1, CELL *npt USES_REGS)
{
register CELL **to_visit = (CELL **)ASP;
tr_fr_ptr OLDTR = TR;
int out;
CELL *bindings = NULL, *tbindings = NULL;
HB = HR;
loop:
while (pt0 < pt0_end) {
register CELL d0, d1;
++ pt0;
++ pt1;
d0 = Derefa(pt0);
d1 = Derefa(pt1);
if (d0 == d1) {
*npt++ = d0;
continue;
} else if (IsVarTerm(d0)) {
CELL *match, *omatch = NULL;
match = VarOfTerm(d0);
if (match >= HB) {
while (match >= HB) {
/* chained to a sequence */
if (Yap_eq(d1, match[1]) ) {
*npt++ = match[2];
break;
}
omatch = match;
match = (CELL *)match[3];
}
/* found a match */
if (match >= HB)
continue;
/* could not find a match, add to end of chain */
RESET_VARIABLE(HR); /* key */
HR[1] = d1; /* comparison value */
HR[2] = (CELL)npt; /* new value */
HR[3] = (CELL)match; /* end of chain points back to first cell */
omatch[3] = (CELL)HR;
HR+=4;
RESET_VARIABLE(npt);
npt++;
continue;
}
if (TR > (tr_fr_ptr)LOCAL_TrailTop - 256) {
goto trail_overflow;
}
RESET_VARIABLE(HR);
HR[1] = d1;
HR[2] = (CELL)npt;
HR[3] = d0;
YapBind(VarOfTerm(d0), (CELL)HR);
HR+=4;
RESET_VARIABLE(npt);
npt++;
continue;
} else if (IsPairTerm(d0) && IsPairTerm(d1)) {
CELL *match = bindings;
while (match) {
if (match[0] == d0 && match[1] == d1) {
*npt++ = match[2];
break;
}
match = (CELL *)match[3];
}
if (match) {
continue;
}
if (bindings) {
*tbindings = (CELL)HR;
} else {
bindings = HR;
}
HR[0] = d0;
HR[1] = d1;
HR[2] = AbsPair(HR+4);
HR[3] = (CELL)NULL;
tbindings = HR+3;
HR+=4;
*npt++ = AbsPair(HR);
#ifdef RATIONAL_TREES
/* now link the two structures so that no one else will */
/* come here */
to_visit -= 5;
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit[3] = tbindings;
to_visit[4] = npt;
#else
/* store the terms to visit */
if (pt0 < pt0_end) {
to_visit -= 4;
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit[3] = npt;
}
#endif
pt0 = RepPair(d0) - 1;
pt0_end = RepPair(d0) + 1;
pt1 = RepPair(d1) - 1;
npt = HR;
HR += 2;
if (HR > (CELL *)to_visit -1024)
goto stack_overflow;
continue;
} else if (IsApplTerm(d0) && IsApplTerm(d1)) {
CELL *ap2 = RepAppl(d0);
CELL *ap3 = RepAppl(d1);
Functor f = (Functor)(*ap2);
Functor f2 = (Functor)(*ap3);
if (f == f2) {
CELL *match = bindings;
if (IsExtensionFunctor(f)) {
if (unify_extension(f, d0, ap2, d1)) {
*npt++ = d0;
continue;
}
}
while (match) {
if (match[0] == d0 && match[1] == d1) {
*npt++ = match[2];
break;
}
match = (CELL *)match[3];
}
if (match) {
continue;
}
if (bindings) {
*tbindings = (CELL)HR;
} else {
bindings = HR;
}
HR[0] = d0;
HR[1] = d1;
HR[2] = AbsAppl(HR+4);
HR[3] = (CELL)NULL;
tbindings = HR+3;
HR+=4;
*npt++ = AbsAppl(HR);
#ifdef RATIONAL_TREES
/* now link the two structures so that no one else will */
/* come here */
to_visit -= 5;
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit[3] = tbindings;
to_visit[4] = npt;
#else
/* store the terms to visit */
if (pt0 < pt0_end) {
to_visit -= 4;
to_visit[0] = pt0;
to_visit[1] = pt0_end;
to_visit[2] = pt1;
to_visit[3] = npt;
}
#endif
d0 = ArityOfFunctor(f);
pt0 = ap2;
pt0_end = ap2 + d0;
pt1 = ap3;
npt = HR;
*npt++ = (CELL)f;
HR += d0;
if (HR > (CELL *)to_visit -1024)
goto stack_overflow;
continue;
}
}
RESET_VARIABLE(npt);
npt++;
}
/* Do we still have compound terms to visit */
if (to_visit < (CELL **)ASP) {
#ifdef RATIONAL_TREES
pt0 = to_visit[0];
pt0_end = to_visit[1];
pt1 = to_visit[2];
tbindings = to_visit[3];
npt = to_visit[ 4];
if (!tbindings) {
bindings = NULL;
}
to_visit += 5;
#else
pt0 = to_visit[0];
pt0_end = to_visit[1];
pt1 = to_visit[2];
npt = to_visit[3];
to_visit += 4;
#endif
goto loop;
}
out = 1;
complete:
/* get rid of intermediate variables */
while (TR != OLDTR) {
CELL *pt1 = (CELL *) TrailTerm(--TR);
RESET_VARIABLE(pt1);
}
HBREG = B->cp_h;
return out;
stack_overflow:
out = -1;
goto complete;
trail_overflow:
out = -2;
goto complete;
}
static Int
p_term_subsumer( USES_REGS1 ) /* term_subsumer terms t1 and t2 */
{
int out = 0;
while (out != 1) {
Term t1 = Deref(ARG1);
Term t2 = Deref(ARG2);
CELL *oldH = HR;
if (t1 == t2)
return Yap_unify(ARG3,t1);
if (IsPairTerm(t1) && IsPairTerm(t2)) {
Term tf = AbsAppl(HR);
HR += 2;
HB = HR;
if ((out = term_subsumer_complex(RepPair(t1)-1,
RepPair(t1)+1,
RepPair(t2)-1, HR-2 PASS_REGS)) > 0) {
HB = B->cp_h;
return Yap_unify(ARG3,tf);
}
} else if (IsApplTerm(t1) && IsApplTerm(t2)) {
Functor f1;
if ((f1 = FunctorOfTerm(t1)) == FunctorOfTerm(t2)) {
if (IsExtensionFunctor(f1)) {
if (unify_extension(f1, t1, RepAppl(t1), t2)) {
return Yap_unify(ARG3,t1);
}
} else {
Term tf = AbsAppl(HR);
UInt ar = ArityOfFunctor(f1);
HR[0] = (CELL)f1;
HR += 1+ar;
HB = HR;
if ((out = term_subsumer_complex(RepAppl(t1),
RepAppl(t1)+ArityOfFunctor(f1),
RepAppl(t2), HR-ar PASS_REGS)) > 0) {
HB = B->cp_h;
return Yap_unify(ARG3,tf);
}
}
}
}
HB = B->cp_h;
if (out == 0) {
return Yap_unify(ARG3, MkVarTerm());
} else {
HR = oldH;
if (out == -1) {
if (!Yap_gcl((ASP-HR)*sizeof(CELL), 0, ENV, gc_P(P,CP))) {
Yap_Error(RESOURCE_ERROR_STACK, TermNil, "in term_subsumer");
return FALSE;
}
} else {
/* Trail overflow */
if (!Yap_growtrail(0, FALSE)) {
Yap_Error(RESOURCE_ERROR_TRAIL, TermNil, "in term_subsumer");
return FALSE;
}
}
}
}
return FALSE;
}
#ifdef DEBUG
static Int
p_force_trail_expansion( USES_REGS1 )
{
Int i = IntOfTerm(Deref(ARG1))*1024, j = 0;
tr_fr_ptr OTR = TR;
for (j = 0; j < i; j++) {
TrailTerm(TR) = 0;
TR++;
}
TR = OTR;
return(TRUE);
}
static Int
camacho_dum( USES_REGS1 )
{
Term t1, t2;
int max = 3;
/* build output list */
t1 = TermNil;
t2 = MkPairTerm(MkIntegerTerm(max), t1);
return(Yap_unify(t2, ARG1));
}
#endif /* DEBUG */
bool
Yap_IsListTerm(Term t)
{
Term *tailp;
Yap_SkipList(&t, &tailp);
return *tailp == TermNil;
}
static Int
p_is_list( USES_REGS1 )
{
return Yap_IsListTerm(Deref(ARG1));
}
bool
Yap_IsListOrPartialListTerm(Term t)
{
Term *tailp, tail;
Yap_SkipList(&t, &tailp);
tail = *tailp;
return tail == TermNil || IsVarTerm(tail);
}
static Int
p_is_list_or_partial_list( USES_REGS1 )
{
return Yap_IsListOrPartialListTerm(Deref(ARG1));
}
#if 0
static Term
numbervar_singleton(USES_REGS1)
{
Term ts[1];
ts[0] = MkIntegerTerm(-1);
return Yap_MkApplTerm(FunctorDollarVar, 1, ts);
}
static void
renumbervar(Term t, Int id USES_REGS)
{
Term *ts = RepAppl(t);
ts[1] = MkIntegerTerm(id);
}
#endif
static int
unnumber_complex_term(CELL *pt0, CELL *pt0_end, CELL *ptf, CELL *HLow, int share USES_REGS)
{
struct cp_frame *to_visit0, *to_visit = (struct cp_frame *)Yap_PreAllocCodeSpace();
CELL *HB0 = HB;
tr_fr_ptr TR0 = TR;
int ground = share;
Int max = -1;
int lvl = push_text_stack();
HB = HLow;
to_visit0 = to_visit;
loop:
while (pt0 < pt0_end) {
register CELL d0;
register CELL *ptd0;
++ pt0;
ptd0 = pt0;
d0 = *ptd0;
deref_head(d0, unnumber_term_unk);
unnumber_term_nvar:
{
if (IsPairTerm(d0)) {
CELL *ap2 = RepPair(d0);
if (ap2 >= HB && ap2 < HR) {
/* If this is newer than the current term, just reuse */
*ptf++ = d0;
continue;
}
*ptf = AbsPair(HR);
ptf++;
if (to_visit+1 >= (struct cp_frame *)AuxSp) {
goto heap_overflow;
}
to_visit->start_cp = pt0;
to_visit->end_cp = pt0_end;
to_visit->to = ptf;
to_visit->oldv = *pt0;
to_visit->ground = ground;
/* fool the system into thinking we had a variable there */
*pt0 = AbsPair(HR);
to_visit ++;
ground = share;
pt0 = ap2 - 1;
pt0_end = ap2 + 1;
ptf = HR;
HR += 2;
if (HR > ASP - 2048) {
goto overflow;
}
} else if (IsApplTerm(d0)) {
register Functor f;
register CELL *ap2;
/* store the terms to visit */
ap2 = RepAppl(d0);
if (ap2 >= HB && ap2 <= HR) {
/* If this is newer than the current term, just reuse */
*ptf++ = d0;
continue;
}
f = (Functor)(*ap2);
if (IsExtensionFunctor(f)) {
*ptf++ = d0; /* you can just unnumber other extensions. */
continue;
}
if (f == FunctorDollarVar) {
Int id = IntegerOfTerm(ap2[1]);
ground = FALSE;
if (id < -1) {
pop_text_stack(lvl);
Yap_Error(RESOURCE_ERROR_STACK, TermNil, "unnumber vars cannot cope with VAR(-%d)", id);
return 0L;
}
if (id <= max) {
if (ASP-(max+1) <= HR) {
goto overflow;
}
/* we found this before? */
if (ASP[-id-1])
*ptf++ = ASP[-id-1];
else {
RESET_VARIABLE(ptf);
ASP[-id-1] = (CELL)ptf;
ptf++;
}
continue;
}
/* alloc more space */
if (ASP-(id+1) <= HR) {
goto overflow;
}
while (id > max) {
ASP[-(id+1)] = 0L;
max++;
}
/* new variable */
RESET_VARIABLE(ptf);
ASP[-(id+1)] = (CELL)ptf;
ptf++;
continue;
}
*ptf = AbsAppl(HR);
ptf++;
/* store the terms to visit */
if (to_visit+1 >= (struct cp_frame *)AuxSp) {
goto heap_overflow;
}
to_visit->start_cp = pt0;
to_visit->end_cp = pt0_end;
to_visit->to = ptf;
to_visit->oldv = *pt0;
to_visit->ground = ground;
/* fool the system into thinking we had a variable there */
*pt0 = AbsAppl(HR);
to_visit ++;
ground = (f != FunctorMutable) && share;
d0 = ArityOfFunctor(f);
pt0 = ap2;
pt0_end = ap2 + d0;
/* store the functor for the new term */
HR[0] = (CELL)f;
ptf = HR+1;
HR += 1+d0;
if (HR > ASP - 2048) {
goto overflow;
}
} else {
/* just unnumber atoms or integers */
*ptf++ = d0;
}
continue;
}
derefa_body(d0, ptd0, unnumber_term_unk, unnumber_term_nvar);
/* this should never happen ? */
ground = FALSE;
*ptf++ = (CELL) ptd0;
}
/* Do we still have compound terms to visit */
if (to_visit > to_visit0) {
to_visit --;
if (ground) {
CELL old = to_visit->oldv;
CELL *newp = to_visit->to-1;
CELL new = *newp;
*newp = old;
if (IsApplTerm(new))
HR = RepAppl(new);
else
HR = RepPair(new);
}
pt0 = to_visit->start_cp;
pt0_end = to_visit->end_cp;
ptf = to_visit->to;
#ifdef RATIONAL_TREES
*pt0 = to_visit->oldv;
#endif
ground = (ground && to_visit->ground);
goto loop;
}
/* restore our nice, friendly, term to its original state */
clean_dirty_tr(TR0 PASS_REGS);
HB = HB0;
pop_text_stack(lvl);
return ground;
overflow:
/* oops, we're in trouble */
HR = HLow;
/* we've done it */
/* restore our nice, friendly, term to its original state */
HB = HB0;
while (to_visit > to_visit0) {
to_visit --;
pt0 = to_visit->start_cp;
pt0_end = to_visit->end_cp;
ptf = to_visit->to;
*pt0 = to_visit->oldv;
}
reset_trail(TR0);
/* follow chain of multi-assigned variables */
pop_text_stack(lvl);
return -1;
heap_overflow:
/* oops, we're in trouble */
HR = HLow;
/* we've done it */
/* restore our nice, friendly, term to its original state */
HB = HB0;
while (to_visit > to_visit0) {
to_visit --;
pt0 = to_visit->start_cp;
pt0_end = to_visit->end_cp;
ptf = to_visit->to;
*pt0 = to_visit->oldv;
}
reset_trail(TR0);
LOCAL_Error_Size = (ADDR)AuxSp-(ADDR)to_visit0;
pop_text_stack(lvl);
return -3;
}
static Term
UnnumberTerm(Term inp, UInt arity, int share USES_REGS) {
Term t = Deref(inp);
tr_fr_ptr TR0 = TR;
if (IsVarTerm(t)) {
return inp;
} else if (IsPrimitiveTerm(t)) {
return t;
} else if (IsPairTerm(t)) {
Term tf;
CELL *ap;
CELL *Hi;
restart_list:
ap = RepPair(t);
Hi = HR;
tf = AbsPair(HR);
HR += 2;
{
int res;
if ((res = unnumber_complex_term(ap-1, ap+1, Hi, Hi, share PASS_REGS)) < 0) {
HR = Hi;
if ((t = handle_cp_overflow(res, TR0, arity, t))== 0L)
return FALSE;
goto restart_list;
} else if (res) {
HR = Hi;
return t;
}
}
return tf;
} else {
Functor f = FunctorOfTerm(t);
Term tf;
CELL *HB0;
CELL *ap;
restart_appl:
f = FunctorOfTerm(t);
HB0 = HR;
ap = RepAppl(t);
tf = AbsAppl(HR);
HR[0] = (CELL)f;
HR += 1+ArityOfFunctor(f);
if (HR > ASP-128) {
HR = HB0;
if ((t = handle_cp_overflow(-1, TR0, arity, t))== 0L)
return FALSE;
goto restart_appl;
} else {
int res;
if ((res = unnumber_complex_term(ap, ap+ArityOfFunctor(f), HB0+1, HB0, share PASS_REGS)) < 0) {
HR = HB0;
if ((t = handle_cp_overflow(res, TR0, arity, t))== 0L)
return FALSE;
goto restart_appl;
} else if (res && FunctorOfTerm(t) != FunctorMutable) {
HR = HB0;
return t;
}
}
return tf;
}
}
Term
Yap_UnNumberTerm(Term inp, int share) {
CACHE_REGS
return UnnumberTerm(inp, 0, share PASS_REGS);
}
static Int
p_unnumbervars( USES_REGS1 ) {
/* this should be a standard Prolog term, so we allow sharing? */
return Yap_unify(UnnumberTerm(ARG1, 2, FALSE PASS_REGS), ARG2);
}
Int
Yap_SkipList(Term *l, Term **tailp)
{
Int length = 0;
Term *s; /* slow */
Term v; /* temporary */
do_derefa(v,l,derefa_unk,derefa_nonvar);
s = l;
if ( IsPairTerm(*l) )
{ intptr_t power = 1, lam = 0;
do
{ if ( power == lam )
{ s = l;
power *= 2;
lam = 0;
}
lam++;
length++;
l = RepPair(*l)+1;
do_derefa(v,l,derefa2_unk,derefa2_nonvar);
} while ( *l != *s && IsPairTerm(*l) );
}
*tailp = l;
return length;
}
static Int
p_skip_list( USES_REGS1 ) {
Term *tail;
Int len = Yap_SkipList(XREGS+2, &tail);
return Yap_unify(MkIntegerTerm(len), ARG1) &&
Yap_unify(*tail, ARG3);
}
static Int
p_skip_list4( USES_REGS1 ) {
Term *tail;
Int len, len1 = -1;
Term t2 = Deref(ARG2), t;
if (!IsVarTerm(t2)) {
if (!IsIntegerTerm(t2)) {
Yap_Error(TYPE_ERROR_INTEGER, t2, "length/2");
return FALSE;
}
if ((len1 = IntegerOfTerm(t2)) < 0) {
Yap_Error(DOMAIN_ERROR_NOT_LESS_THAN_ZERO, t2, "length/2");
return FALSE;
}
}
/* we need len here */
len = Yap_SkipList(XREGS+1, &tail);
t = *tail;
/* don't set M0 if full list, just check M */
if (t == TermNil) {
if (len1 >= 0) { /* ARG2 was bound */
return
len1 == len &&
Yap_unify(t, ARG4);
} else {
return Yap_unify_constant(ARG4, TermNil) &&
Yap_unify_constant(ARG2, MkIntegerTerm(len));
}
}
return Yap_unify(MkIntegerTerm(len), ARG3) &&
Yap_unify(t, ARG4);
}
static Int
p_free_arguments( USES_REGS1 )
{
Term t = Deref(ARG1);
if (IsVarTerm(t))
return FALSE;
if (IsAtomTerm(t) || IsIntTerm(t))
return TRUE;
if (IsPairTerm(t)) {
Term th = HeadOfTerm(t);
Term tl = TailOfTerm(t);
return IsVarTerm(th) && IsVarTerm(tl) && th != tl;
} else {
Functor f = FunctorOfTerm(t);
UInt i, ar;
Int ret = TRUE;
if (IsExtensionFunctor(f))
return TRUE;
ar = ArityOfFunctor(f);
for (i = 1 ; i <= ar; i++) {
Term ta = ArgOfTerm(i, t);
Int j;
ret = IsVarTerm(ta);
if (!ret) break;
/* stupid quadractic algorithm, but needs no testing for overflows */
for (j = 1 ; j < i; j++) {
ret = ArgOfTerm(j, t) != ta;
if (!ret) break;
}
if (!ret) break;
}
return ret;
}
}
static Int
p_freshen_variables( USES_REGS1 )
{
Term t = Deref(ARG1);
Functor f = FunctorOfTerm(t);
UInt arity = ArityOfFunctor(f), i;
Term tn = Yap_MkNewApplTerm(f, arity);
CELL *src = RepAppl(t)+1;
CELL *targ = RepAppl(tn)+1;
for (i=0; i< arity; i++) {
RESET_VARIABLE(targ);
*VarOfTerm(*src) = (CELL)targ;
targ++;
src++;
}
return TRUE;
}
static Int
p_reset_variables( USES_REGS1 )
{
Term t = Deref(ARG1);
Functor f = FunctorOfTerm(t);
UInt arity = ArityOfFunctor(f), i;
CELL *src = RepAppl(t)+1;
for (i=0; i< arity; i++) {
RESET_VARIABLE(VarOfTerm(*src));
src++;
}
return TRUE;
}
void Yap_InitUtilCPreds(void)
{
CACHE_REGS
Term cm = CurrentModule;
Yap_InitCPred("copy_term", 2, p_copy_term, 0);
/** @pred copy_term(? _TI_,- _TF_) is iso
Term _TF_ is a variant of the original term _TI_, such that for
each variable _V_ in the term _TI_ there is a new variable _V'_
in term _TF_. Notice that:
+ suspended goals and attributes for attributed variables in _TI_ are also duplicated;
+ ground terms are shared between the new and the old term.
If you do not want any sharing to occur please use
duplicate_term/2.
*/
Yap_InitCPred("duplicate_term", 2, p_duplicate_term, 0);
/** @pred duplicate_term(? _TI_,- _TF_)
Term _TF_ is a variant of the original term _TI_, such that
for each variable _V_ in the term _TI_ there is a new variable
_V'_ in term _TF_, and the two terms do not share any
structure. All suspended goals and attributes for attributed variables
in _TI_ are also duplicated.
Also refer to copy_term/2.
*/
Yap_InitCPred("copy_term_nat", 2, p_copy_term_no_delays, 0);
/** @pred copy_term_nat(? _TI_,- _TF_)
As copy_term/2. Attributes however, are <em>not</em> copied but replaced
by fresh variables.
*/
Yap_InitCPred("is_list", 1, p_is_list, SafePredFlag|TestPredFlag);
Yap_InitCPred("$is_list_or_partial_list", 1, p_is_list_or_partial_list, SafePredFlag|TestPredFlag);
/** @pred term_factorized(? _TI_,- _TF_, ?SubTerms)
Similar to rational_term_to_tree/4, but _SubTerms_ is a proper list.
*/
Yap_InitCPred("=@=", 2, p_variant, 0);
Yap_InitCPred("unnumbervars", 2, p_unnumbervars, 0);
/** @pred unnumbervars( _T_,+ _NT_)
Replace every `$VAR( _I_)` by a free variable.
*/
/* use this carefully */
Yap_InitCPred("$skip_list", 3, p_skip_list, SafePredFlag|TestPredFlag);
Yap_InitCPred("$skip_list", 4, p_skip_list4, SafePredFlag|TestPredFlag);
Yap_InitCPred("$free_arguments", 1, p_free_arguments, TestPredFlag);
CurrentModule = TERMS_MODULE;
Yap_InitCPred("term_hash", 4, p_term_hash, 0);
Yap_InitCPred("instantiated_term_hash", 4, p_instantiated_term_hash, 0);
Yap_InitCPred("variant", 2, p_variant, 0);
Yap_InitCPred("subsumes", 2, p_subsumes, 0);
Yap_InitCPred("term_subsumer", 3, p_term_subsumer, 0);
Yap_InitCPred("export_term", 3, p_export_term, 0);
Yap_InitCPred("kill_exported_term", 1, p_kill_exported_term, SafePredFlag);
Yap_InitCPred("import_term", 2, p_import_term, 0);
Yap_InitCPred("freshen_variables", 1, p_freshen_variables, 0);
Yap_InitCPred("reset_variables", 1, p_reset_variables, 0);
CurrentModule = cm;
#ifdef DEBUG
Yap_InitCPred("$force_trail_expansion", 1, p_force_trail_expansion, SafePredFlag);
Yap_InitCPred("dum", 1, camacho_dum, SafePredFlag);
#endif
}