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yap-6.3/H/heapgc.h
2004-04-22 20:07:07 +00:00

151 lines
4.7 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: heapgc.c *
* Last rev: *
* mods: *
* comments: Header for Global Stack garbage collector *
* *
*************************************************************************/
/* macros used by garbage collection */
#if TAG_64BITS
#define MaskAdr (~(MBIT|RBIT|0x7L))
#endif
/* return pointer from object pointed to by ptr (remove tag & mark) */
#ifdef TAGS_FAST_OPS
#define GET_NEXT(val) ((CELL *)(IsVarTerm((val)) ? \
(val) & MaskAdr : \
( IsPairTerm((val)) ? \
Unsigned(RepPair((val))) & MaskAdr : \
( IsApplTerm((val)) ? \
Unsigned(RepAppl((val))) & MaskAdr : \
(val) & MaskAdr \
) \
) \
) \
)
#else
#ifdef TAG_LOW_BITS_32
#if INVERT_RBIT
#define GET_NEXT(val) ((CELL *) (((val) & ~(LowTagBits|MBIT))|RBIT))
#else
#define GET_NEXT(val) ((CELL *) ((val) & ~(LowTagBits|MBIT|RBIT)))
#endif
#else
#define GET_NEXT(val) ((CELL *) ((val) & MaskAdr))
#endif
#endif
/* is ptr a pointer to the heap? */
#define ONHEAP(ptr) (CellPtr(ptr) >= H0 && CellPtr(ptr) < H)
/* is ptr a pointer to code space? */
#if USE_SYSTEM_MALLOC
#define ONCODE(ptr) (Addr(ptr) < Yap_GlobalBase || Addr(ptr) > Yap_TrailTop)
#else
#define ONCODE(ptr) (Addr(ptr) < HeapTop && Addr(ptr) >= Yap_HeapBase)
#endif
/* is val pointing to something bound to the heap? */
#define GCIsPrimitiveTerm(X) (!IsVarTerm(X) && IsAtomOrIntTerm(X))
/* Does X point to an object in the heap */
#define HEAP_PTR(val) (!GCIsPrimitiveTerm(val) && ONHEAP(GET_NEXT(val)))
/*
Heap_trail_entry must be very careful. We are looking at a valid
trail entry if: it was between H0 and HB or between B and LCLO
(that is, if it was covered by choicepoints at the time), and if it
was a heap pointer.
We can join the two conditions: (H0 =< val < HB || ((B < val < LCL0)
&& H0 <= *DETAG(val) < H))
*/
#define HEAP_TRAIL_ENTRY(val) ((IsVarTerm(val)) && \
((H0 <= CellPtr(val) && CellPtr(val)\
< cp_H) || \
(CellPtr(B) < CellPtr(val) && CellPtr(val) <= \
LCL0 && HEAP_PTR(val))))
/* is the object pointed to by ptr marked? */
#ifdef TAGS_FAST_OPS
#define MARKED_VAR(val) ((val) & MBIT)
#define MARKED_COMP(val) (!((val) & MBIT))
#define MARKED(val) ((Int)(val) < 0 && (((val) & LowTagBits) != 2)\
? \
!((val) & MBIT) : ((val) & MBIT))
#else
#define MARKED(val) ((val) & MBIT)
#endif
#define MARK(ptr) (*(ptr) ^= MBIT) /* mark the object pointed to by ptr */
#define MARK_CELL(val) ((val) ^ MBIT) /* mark the object pointed to by ptr */
#define UNMARK(ptr) (*(ptr) ^= MBIT) /* unmark the object pointed to by ptr */
#define UNMARK_CELL(val) ((val) ^ MBIT) /* unmark the object pointed to by ptr */
#ifdef TAGS_FAST_OPS
#define RMARKED(val) (!GCIsPrimitiveTerm(val) && (IsVarTerm(val) ?\
((val) & RBIT) : !((val) & RBIT)))
#define UNMARKED(val) ((Int)(val) < 0 && (((val) & LowTagBits) != 2)\
? \
((val) | MBIT) : ((val) & ~MBIT))
#define ENSURE_MARKED(val) ((Int)(val) < 0 && (((val) & LowTagBits) != 2)\
? \
((val) & ~MBIT) : ((val) | MBIT))
#else
#if INVERT_RBIT
#define RMARKED(val) (!GCIsPrimitiveTerm(val) && !((val) & RBIT))
#else
#define RMARKED(val) (!GCIsPrimitiveTerm(val) && ((val) & RBIT))
#endif
#endif
/* is the object pointed to by ptr marked as in a relocation chain? */
#if LONG_ADDRESSES
#ifdef TAG_LOW_BITS_32
#define TAG(X) ((X) & LowTagBits)
#else
#ifdef TAG_64BITS
#define TAG(X) ((X) & MKTAG(0x0,0x7))
#else
#define TAG(X) ((X) & 0x80000003L)
#endif
#endif
#else
#define TAG(X) ((X) & 0x98000000L)
#endif
typedef CELL *CELL_PTR;
#define ENVSIZE(E) EnvSize(((CELL *)E)[E_CP])
void STD_PROTO(Yap_mark_variable, (CELL *));
void STD_PROTO(Yap_mark_external_reference, (CELL *));
void STD_PROTO(Yap_inc_mark_variable, (void));