path: root/erts/emulator/beam/erl_gc.h

/*
 * %CopyrightBegin%
 *
 * Copyright Ericsson AB 2007-2016. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * %CopyrightEnd%
 */

#ifndef __ERL_GC_H__
#define __ERL_GC_H__

#if defined(ERL_WANT_GC_INTERNALS__) || defined(ERTS_DO_INCL_GLB_INLINE_FUNC_DEF)

/* GC declarations shared by beam/erl_gc.c and hipe/hipe_gc.c */

#define ERTS_POTENTIALLY_LONG_GC_HSIZE (128*1024) /* Words */

#include "erl_map.h"
#include "erl_fun.h"
#include "erl_bits.h"

#define IS_MOVED_BOXED(x)	(!is_header((x)))
#define IS_MOVED_CONS(x)	(is_non_value((x)))

#define MOVE_CONS(PTR,CAR,HTOP,ORIG)					\
do {									\
    Eterm gval;								\
									\
    HTOP[0] = CAR;		/* copy car */				\
    HTOP[1] = PTR[1];		/* copy cdr */				\
    gval = make_list(HTOP);	/* new location */			\
    *ORIG = gval;		/* redirect original reference */	\
    PTR[0] = THE_NON_VALUE;	/* store forwarding indicator */	\
    PTR[1] = gval;		/* store forwarding address */		\
    HTOP += 2;			/* update tospace htop */		\
} while(0)

#define MOVE_BOXED(PTR,HDR,HTOP,ORIG) \
    do { \
        move_boxed(&(PTR), HDR, &(HTOP), ORIG); \
    } while(0)

void erts_sub_binary_to_heap_binary(Eterm **pp, Eterm **hpp, Eterm *orig);
ERTS_GLB_INLINE void move_boxed(Eterm **pp, Eterm hdr, Eterm **hpp, Eterm *orig);

#if ERTS_GLB_INLINE_INCL_FUNC_DEF
ERTS_GLB_INLINE void move_boxed(Eterm **pp, Eterm hdr, Eterm **hpp, Eterm *orig)
{
    Eterm gval;
    Sint nelts;
    Eterm *ptr = *pp;
    Eterm *htop = *hpp;

    ASSERT(is_header(hdr));
    nelts = header_arity(hdr);
    switch ((hdr) & _HEADER_SUBTAG_MASK) {
    case SUB_BINARY_SUBTAG:
        {
            ErlSubBin *sb = (ErlSubBin *)ptr;
            /* convert sub-binary to heap-binary if applicable */
            if (sb->bitsize == 0 && sb->bitoffs == 0 &&
                sb->is_writable == 0 && sb->size <= sizeof(Eterm) * 3) {
                erts_sub_binary_to_heap_binary(pp, hpp, orig);
                return;
            }
        }
        nelts++;
        break;
    case MAP_SUBTAG:
        if (is_flatmap_header(hdr)) nelts+=flatmap_get_size(ptr) + 1;
        else nelts += hashmap_bitcount(MAP_HEADER_VAL(hdr));
    break;
    case FUN_SUBTAG: nelts+=((ErlFunThing*)(ptr))->num_free+1; break;
    }
    gval    = make_boxed(htop);
    *orig   = gval;
    *htop++ = hdr;
    *ptr++  = gval;
    while (nelts--) *htop++ = *ptr++;

    *hpp = htop;
    *pp  = ptr;
}
#endif

#define ErtsInYoungGen(TPtr, Ptr, OldHeap, OldHeapSz)			\
    (!erts_is_literal((TPtr), (Ptr))					\
     & !ErtsInArea((Ptr), (OldHeap), (OldHeapSz)))

ERTS_GLB_INLINE Eterm follow_moved(Eterm term, Eterm xptr_tag);

#if ERTS_GLB_INLINE_INCL_FUNC_DEF
ERTS_GLB_INLINE Eterm follow_moved(Eterm term, Eterm xptr_tag)
{
    Eterm* ptr;
    switch (primary_tag(term)) {
    case TAG_PRIMARY_IMMED1:
	break;
    case TAG_PRIMARY_BOXED:
	ptr = boxed_val(term);
	if (IS_MOVED_BOXED(*ptr)) term = (*ptr) | xptr_tag;
	break;
    case TAG_PRIMARY_LIST:
	ptr = list_val(term);
	if (IS_MOVED_CONS(ptr[0])) term = (ptr[1]) | xptr_tag;
	break;
    default:
	ASSERT(!"strange tag in follow_moved");
    }
    return term;
}

#endif

#endif /* ERL_GC_C__ || HIPE_GC_C__ */

/*
 * Global exported
 */

#define ERTS_IS_GC_DESIRED_INTERNAL(Proc, HTop, STop)			\
    ((((STop) - (HTop) < (Proc)->mbuf_sz))				\
     | ((Proc)->off_heap.overhead > (Proc)->bin_vheap_sz)		\
     | !!((Proc)->flags & F_FORCE_GC))

#define ERTS_IS_GC_DESIRED(Proc)					\
    ERTS_IS_GC_DESIRED_INTERNAL((Proc), (Proc)->htop, (Proc)->stop)

#define ERTS_FORCE_GC_INTERNAL(Proc, FCalls)				\
    do {								\
	(Proc)->flags |= F_FORCE_GC;					\
	ERTS_VBUMP_ALL_REDS_INTERNAL((Proc), (FCalls));			\
    } while (0)

#define ERTS_FORCE_GC(Proc)						\
    ERTS_FORCE_GC_INTERNAL((Proc), (Proc)->fcalls)

extern Uint erts_test_long_gc_sleep;

typedef struct {
  Uint64 reclaimed;
  Uint64 garbage_cols;
} ErtsGCInfo;

#define ERTS_PROCESS_GC_INFO_MAX_TERMS (11)  /* number of elements in process_gc_info*/
#define ERTS_PROCESS_GC_INFO_MAX_SIZE                                   \
    (ERTS_PROCESS_GC_INFO_MAX_TERMS * (2/*cons*/ + 3/*2-tuple*/ + BIG_UINT_HEAP_SIZE))
Eterm erts_process_gc_info(struct process*, Uint *, Eterm **, Uint, Uint);

void erts_gc_info(ErtsGCInfo *gcip);
void erts_init_gc(void);
int erts_garbage_collect_nobump(struct process*, int, Eterm*, int, int);
void erts_garbage_collect(struct process*, int, Eterm*, int);
void erts_garbage_collect_hibernate(struct process* p);
Eterm erts_gc_after_bif_call_lhf(struct process* p, ErlHeapFragment *live_hf_end,
				 Eterm result, Eterm* regs, Uint arity);
Eterm erts_gc_after_bif_call(struct process* p, Eterm result, Eterm* regs, Uint arity);
int erts_garbage_collect_literals(struct process* p, Eterm* literals,
				  Uint lit_size,
				  struct erl_off_heap_header* oh,
				  int fcalls);
Uint erts_next_heap_size(Uint, Uint);
Eterm erts_heap_sizes(struct process* p);

void erts_offset_off_heap(struct erl_off_heap*, Sint, Eterm*, Eterm*);
void erts_offset_heap_ptr(Eterm*, Uint, Sint, Eterm*, Eterm*);
void erts_offset_heap(Eterm*, Uint, Sint, Eterm*, Eterm*);
void erts_free_heap_frags(struct process* p);
Eterm erts_max_heap_size_map(Sint, Uint, Eterm **, Uint *);
int erts_max_heap_size(Eterm, Uint *, Uint *);
void erts_deallocate_young_generation(Process *c_p);
#if defined(DEBUG) || defined(ERTS_OFFHEAP_DEBUG)
int erts_dbg_within_proc(Eterm *ptr, Process *p, Eterm* real_htop);
#endif

#endif /* __ERL_GC_H__ */