copy.c

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        (hp) = erts_inc_alloc(n);                                       \
    } else {                                                            \
        (hp) = IncAlloc((p),n,&dest,1);                                 \
        if (ma_gc_flags & GC_CYCLE_START) {                             \
            alloc_old = 1;                                              \
            global_htop = global_heap;                                  \
            (hp) = erts_inc_alloc(n);                                   \
        }                                                               \
    }                                                                   \
    CLEARMEM((hp),(n));                                                 \
    BM_SWAP_TIMER(system,copy);                                         \
} while(0)

#else /* no INCREMELNTAL */

#define GlobalAlloc(p, need, hp)                                        \
do {                                                                    \
    Uint n = (need);                                                    \
    total_need += n;                                                    \
    if (total_need >= global_heap_sz)                                   \
        erl_exit(ERTS_ABORT_EXIT, "Copying a message (%d words) larger than the nursery simply won't work...\n", total_need); \
    if (global_hend - n < global_htop) {                                \
        BM_SWAP_TIMER(copy,system);                                     \
        erts_global_garbage_collect((p),total_need,NULL,0);             \
        BM_SWAP_TIMER(system,copy);                                     \
        total_need = 0;                                                 \
        ma_src_top = 0;                                                 \
        ma_dst_top = 0;                                                 \
        ma_offset_top = 0;                                              \
        goto copy_start;                                                \
    }                                                                   \
    (hp) = global_htop;                                                 \
    global_htop += n;                                                   \
    BM_ADD(words_copied,n);                                             \
} while(0)
#endif /* INCREMENTAL */

/* Copy a message to the message area. */
Eterm copy_struct_lazy(Process *from, Eterm orig, Uint offs)
{
    Eterm obj;
    Eterm dest;
#ifdef INCREMENTAL
    int alloc_old = 0;
#else
    int total_need = 0;
#endif

    VERBOSE(DEBUG_MESSAGES,
            ("COPY START; %T is sending a message @ 0x%016x\n%T\n",
             from->id, orig, orig));

#ifndef INCREMENTAL
 copy_start:
#endif
    MA_STACK_PUSH(src,orig);
    MA_STACK_PUSH(dst,&dest);
    MA_STACK_PUSH(offset,offs);

    while (ma_src_top > 0) {
        obj = MA_STACK_POP(src);

        /* copy_struct_lazy should never be called with something that
         * do not need to be copied. Within the loop, nothing that do
         * not need copying should be placed in the src-stack.
         */
        ASSERT(!NO_COPY(obj));

        switch (primary_tag(obj)) {
        case TAG_PRIMARY_LIST: {
            Eterm *hp;
            Eterm *objp;

            GlobalAlloc(from,2,hp);
            objp = list_val(obj);

            MA_STACK_UPDATE(dst,MA_STACK_POP(offset),make_list(hp));
            MA_STACK_POP(dst);

            /* TODO: Byt ordningen nedan så att CDR pushas först. */

            if (NO_COPY(*objp)) {
                hp[0] = *objp;
#ifdef INCREMENTAL
                if (ptr_within(ptr_val(*objp),inc_fromspc,inc_fromend))
                    INC_STORE(gray,hp,2);
#endif
            } else {
                MA_STACK_PUSH(src,*objp);
                MA_STACK_PUSH(dst,hp);
                MA_STACK_PUSH(offset,0);
            }

            objp++;

            if (NO_COPY(*objp)) {
                hp[1] = *objp;
#ifdef INCREMENTAL
                if (ptr_within(ptr_val(*objp),inc_fromspc,inc_fromend))
                    INC_STORE(gray,hp,2);
#endif
            }
            else {
                MA_STACK_PUSH(src,*objp);
                MA_STACK_PUSH(dst,hp);
                MA_STACK_PUSH(offset,1);
            }
            continue;
        }

        case TAG_PRIMARY_BOXED: {
            Eterm *objp = boxed_val(obj);

            switch (*objp & _TAG_HEADER_MASK) {
            case ARITYVAL_SUBTAG: {
                Uint ari = arityval(*objp);
                Uint i;
                Eterm *hp;
                GlobalAlloc(from,ari + 1,hp);
                /* A GC above might invalidate the value of objp */
                objp = boxed_val(obj);
                MA_STACK_UPDATE(dst,MA_STACK_POP(offset),make_tuple(hp));
                MA_STACK_POP(dst);
                *hp = *objp++;
                for (i = 1; i <= ari; i++) {
                    switch (primary_tag(*objp)) {
                    case TAG_PRIMARY_LIST:
                    case TAG_PRIMARY_BOXED:
                        if (NO_COPY(*objp)) {
                            hp[i] = *objp;
#ifdef INCREMENTAL
                            if (ptr_within(ptr_val(*objp),
                                           inc_fromspc,inc_fromend))
                                INC_STORE(gray,hp,BOXED_NEED(hp,*hp));
#endif
                            objp++;
                        } else {
                            MA_STACK_PUSH(src,*objp++);
                            MA_STACK_PUSH(dst,hp);
                            MA_STACK_PUSH(offset,i);
                        }
                        break;
                    default:
                        hp[i] = *objp++;
                    }
                }
                continue;
            }

            case REFC_BINARY_SUBTAG: {
                ProcBin *pb;
                Uint i = thing_arityval(*objp) + 1;
                Eterm *hp;
                GlobalAlloc(from,i,hp);
                /* A GC above might invalidate the value of objp */
                objp = boxed_val(obj);
                MA_STACK_UPDATE(dst,MA_STACK_POP(offset),make_binary(hp));
                MA_STACK_POP(dst);
                pb = (ProcBin*) hp;
                while (i--) {
                    *hp++ = *objp++;
                }
                erts_refc_inc(&pb->val->refc, 2);
                pb->next = erts_global_offheap.mso;
                erts_global_offheap.mso = pb;
                erts_global_offheap.overhead += pb->size /
                    BINARY_OVERHEAD_FACTOR / sizeof(Eterm);
                continue;
            }

            case FUN_SUBTAG: {
                ErlFunThing *funp = (ErlFunThing*) objp;
                Uint i = thing_arityval(*objp) + 1;
                Uint j = i + 1 + funp->num_free;
                Uint k = i;
                Eterm *hp, *hp_start;
                GlobalAlloc(from,j,hp);
                /* A GC above might invalidate the value of objp */
                objp = boxed_val(obj);
                hp_start = hp;
                MA_STACK_UPDATE(dst,MA_STACK_POP(offset),make_fun(hp));
                MA_STACK_POP(dst);
                funp = (ErlFunThing*) hp;
                while (i--) {
                    *hp++ = *objp++;
                }
#ifndef HYBRID // FIND ME!
                funp->next = erts_global_offheap.funs;
                erts_global_offheap.funs = funp;
                erts_refc_inc(&funp->fe->refc, 2);
#endif
                for (i = k; i < j; i++) {
                    switch (primary_tag(*objp)) {
                    case TAG_PRIMARY_LIST:
                    case TAG_PRIMARY_BOXED:
                        if (NO_COPY(*objp)) {
#ifdef INCREMENTAL
                            if (ptr_within(ptr_val(*objp),
                                           inc_fromspc,inc_fromend))
                                INC_STORE(gray,hp,BOXED_NEED(hp,*hp));
#endif
                            *hp++ = *objp++;
                        } else {
                            MA_STACK_PUSH(src,*objp++);
                            MA_STACK_PUSH(dst,hp_start);
                            MA_STACK_PUSH(offset,i);
                            hp++;
                        }
                        break;
                    default:
                        *hp++ = *objp++;
                    }
                }
                continue;
            }

            case EXTERNAL_PID_SUBTAG:
            case EXTERNAL_PORT_SUBTAG:
            case EXTERNAL_REF_SUBTAG: {
                ExternalThing *etp;
                Uint i =  thing_arityval(*objp) + 1;
                Eterm *hp;
                GlobalAlloc(from,i,hp);
                /* A GC above might invalidate the value of objp */
                objp = boxed_val(obj);
                MA_STACK_UPDATE(dst,MA_STACK_POP(offset),make_external(hp));
                MA_STACK_POP(dst);
                etp = (ExternalThing*) hp;
                while (i--)  {
                    *hp++ = *objp++;
                }

                etp->next = erts_global_offheap.externals;
                erts_global_offheap.externals = etp;
		erts_refc_inc(&etp->node->refc, 2);
                continue;
            }

            case SUB_BINARY_SUBTAG: {
                ErlSubBin *sb = (ErlSubBin *) objp;
		Eterm *hp;
		Eterm res_binary;
                Eterm real_bin = sb->orig;
                Uint bit_offset = sb->bitoffs;
		Uint bit_size = sb -> bitsize;
		Uint sub_offset = sb->offs;
                size_t size = sb->size;
		Uint extra_bytes;
		Uint real_size;
		Uint sub_binary_heapneed;
		if ((bit_size + bit_offset) > 8) {
		    extra_bytes = 2;
		    sub_binary_heapneed = ERL_SUB_BIN_SIZE;
		}  
		else if ((bit_size + bit_offset) > 0) {
		    extra_bytes = 1;
		    sub_binary_heapneed = ERL_SUB_BIN_SIZE;
		}
		else {
		    extra_bytes = 0;
		    sub_binary_heapneed = 0;
		}
		
		real_size = size+extra_bytes;
                objp = binary_val(real_bin);
                if (thing_subtag(*objp) == HEAP_BINARY_SUBTAG) {
                    ErlHeapBin *from_bin;
                    ErlHeapBin *to_bin;
                    Uint i = heap_bin_size(real_size);
                    GlobalAlloc(from,i+sub_binary_heapneed,hp);
                    from_bin = (ErlHeapBin *) objp;
                    to_bin = (ErlHeapBin *) hp;
                    to_bin->thing_word = header_heap_bin(real_size);
                    to_bin->size = real_size;
                    sys_memcpy(to_bin->data, ((byte *)from_bin->data) +
                               sub_offset, real_size);
		    res_binary=make_binary(to_bin);
		    hp += i;
                } else {
                    ProcBin *from_bin;
                    ProcBin *to_bin;
                    
                    ASSERT(thing_subtag(*objp) == REFC_BINARY_SUBTAG);
		    from_bin = (ProcBin *) objp;
		    erts_refc_inc(&from_bin->val->refc, 2);
                    GlobalAlloc(from,PROC_BIN_SIZE+sub_binary_heapneed,hp);
                    to_bin = (ProcBin *) hp;
                    to_bin->thing_word = HEADER_PROC_BIN;
                    to_bin->size = real_size;
                    to_bin->val = from_bin->val;
                    to_bin->bytes = from_bin->bytes + sub_offset;
                    to_bin->next = erts_global_offheap.mso;
                    erts_global_offheap.mso = to_bin;
                    erts_global_offheap.overhead += to_bin->size /
                        BINARY_OVERHEAD_FACTOR / sizeof(Eterm);
		    res_binary=make_binary(to_bin);
		    hp += PROC_BIN_SIZE;
                }
		if (extra_bytes != 0) {
		      ErlSubBin* res;
		      res = (ErlSubBin *) hp;
		      res->thing_word = HEADER_SUB_BIN;
		      res->size = size;
		      res->bitsize = bit_size;
		      res->bitoffs = bit_offset;
		      res->offs = 0;
		      res->orig = res_binary;
		      res_binary = make_binary(hp);
		    }
		MA_STACK_UPDATE(dst,MA_STACK_POP(offset),res_binary);
		MA_STACK_POP(dst);
                continue;
            }

	    case BIN_MATCHSTATE_SUBTAG:
		erl_exit(ERTS_ABORT_EXIT,
			 "copy_struct_lazy: matchstate term not allowed");

            default: {
                Uint size = thing_arityval(*objp) + 1;
                Eterm *hp;
                GlobalAlloc(from,size,hp);
                /* A GC above might invalidate the value of objp */
                objp = boxed_val(obj);
                MA_STACK_UPDATE(dst,MA_STACK_POP(offset),make_boxed(hp));
                MA_STACK_POP(dst);
                while (size--) {
                    *hp++ = *objp++;
                }
                continue;
            }
            }
            continue;
        }

        case TAG_PRIMARY_HEADER:
        ASSERT((obj & _TAG_HEADER_MASK) == ARITYVAL_SUBTAG);
        {
            Eterm *objp = &obj;
            Uint ari = arityval(obj);
            Uint i;
            Eterm *hp;
            GlobalAlloc(from,ari + 1,hp);
            MA_STACK_UPDATE(dst,MA_STACK_POP(offset),make_tuple(hp));
            MA_STACK_POP(dst);
            *hp = *objp++;
            for (i = 1; i <= ari; i++) {
                switch (primary_tag(*objp)) {
                case TAG_PRIMARY_LIST:
                case TAG_PRIMARY_BOXED:
                    if (NO_COPY(*objp)) {
#ifdef INCREMENTAL
                        if (ptr_within(ptr_val(*objp),inc_fromspc,inc_fromend))
                            INC_STORE(gray,hp,ari + 1);
#endif
                        hp[i] = *objp++;
                    } else {
                        MA_STACK_PUSH(src,*objp++);
                        MA_STACK_PUSH(dst,hp);
                        MA_STACK_PUSH(offset,i);
                    }
                    break;
                default:
                    hp[i] = *objp++;
                }
            }
            continue;
        }

        default:
            erl_exit(ERTS_ABORT_EXIT,
		     "%s, line %d: Internal error in copy_struct_lazy: 0x%08x\n",
                     __FILE__, __LINE__,obj);
        }
    }

    VERBOSE(DEBUG_MESSAGES,
            ("Copy allocated @ 0x%08lx:\n%T\n",
             (unsigned long)ptr_val(dest),dest));

    ma_gc_flags &= ~GC_CYCLE_START;

    ASSERT(eq(orig, dest));
    ASSERT(ma_src_top == 0);
    ASSERT(ma_dst_top == 0);
    ASSERT(ma_offset_top == 0);
    return dest;
}

#undef NO_COPY
#endif /* HYBRID */

/*
 * Copy a term that is guaranteed to be contained in a single
 * heap block. The heap block is copied word by word, and any
 * pointers are offsetted to point correctly in the new location.
 *
 * Typically used to copy a term from an ets table.
 *
 * NOTE: Assumes that term is a tuple (ptr is an untagged tuple ptr).
 */
Eterm
copy_shallow(Eterm* ptr, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
{
    Eterm* tp = ptr;
    Eterm* hp = *hpp;
    Sint offs = hp - tp;

    while (sz--) {
	Eterm val = *tp++;

	switch (primary_tag(val)) {
	case TAG_PRIMARY_IMMED1:
	    *hp++ = val;
	    break;
	case TAG_PRIMARY_LIST:
	case TAG_PRIMARY_BOXED:
	    *hp++ = offset_ptr(val, offs);
	    break;
	case TAG_PRIMARY_HEADER:
	    *hp++ = val;
	    switch (val & _HEADER_SUBTAG_MASK) {
	    case ARITYVAL_SUBTAG:
		break;
	    case REFC_BINARY_SUBTAG:
		{
		    ProcBin* pb = (ProcBin *) (hp-1);
		    int tari = thing_arityval(val);

		    sz -= tari;
		    while (tari--) {
			*hp++ = *tp++;
		    }
		    erts_refc_inc(&pb->val->refc, 2);
		    pb->next = off_heap->mso;
		    off_heap->mso = pb;
		}
		break;
	    case FUN_SUBTAG:
		{
#ifndef HYBRID /* FIND ME! */
		    ErlFunThing* funp = (ErlFunThing *) (hp-1);
#endif
		    int tari = thing_arityval(val);

		    sz -= tari;
		    while (tari--) {
			*hp++ = *tp++;
		    }
#ifndef HYBRID /* FIND ME! */
		    funp->next = off_heap->funs;
		    off_heap->funs = funp;
		    erts_refc_inc(&funp->fe->refc, 2);
#endif
		}
		break;
	    case EXTERNAL_PID_SUBTAG:
	    case EXTERNAL_PORT_SUBTAG:
	    case EXTERNAL_REF_SUBTAG:
		{
		    ExternalThing* etp = (ExternalThing *) (hp-1);
		    int tari = thing_arityval(val);

		    sz -= tari;
		    while (tari--) {
			*hp++ = *tp++;
		    }
		    etp->next = off_heap->externals;
		    off_heap->externals = etp;
		    erts_refc_inc(&etp->node->refc, 2);
		}
		break;
	    default:
		{
		    int tari = header_arity(val);

		    sz -= tari;
		    while (tari--) {
			*hp++ = *tp++;
		    }
		}
		break;
	    }
	    break;
	}
    }
    *hpp = hp;
    return make_tuple(ptr + offs); 
}