HALFWORD ETS relative terms

In halfword emulator, make ETS use a variant of the internal term
format that uses relative offsets instead of absolute pointers. This
will allow storage in high memory (>4G). Preprocessor macros (like
list_val_rel(TERM,BASE)) are used to make normal (fullword) emulator
almost completely unchanged while still reusing most of the code.

17 files changed, 876 insertions, 486 deletions

diff --git a/erts/emulator/beam/big.c b/erts/emulator/beam/big.c
index ff15d834ab..57964b31e4 100644
--- a/erts/emulator/beam/big.c
+++ b/erts/emulator/beam/big.c
@@ -1558,7 +1558,7 @@ Eterm erts_sint64_to_big(Sint64 x, Eterm **hpp)
 ** Convert a bignum to a double float
 */
 int
-big_to_double(Eterm x, double* resp)
+big_to_double(Wterm x, double* resp)
 {
     double d = 0.0;
     Eterm* xp = big_val(x);
@@ -1725,7 +1725,7 @@ static Eterm big_norm(Eterm *x, dsize_t xl, short sign)
 /*
 ** Compare bignums
 */
-int big_comp(Eterm x, Eterm y)
+int big_comp(Wterm x, Wterm y)
 {
     Eterm* xp = big_val(x);
     Eterm* yp = big_val(y);
@@ -2060,7 +2060,7 @@ static Eterm B_plus_minus(ErtsDigit *x, dsize_t xl, short xsgn,
 /*
 ** Add bignums
 */
-Eterm big_plus(Eterm x, Eterm y, Eterm *r)
+Eterm big_plus(Wterm x, Wterm y, Eterm *r)
 {
     Eterm* xp = big_val(x);
     Eterm* yp = big_val(y);
diff --git a/erts/emulator/beam/big.h b/erts/emulator/beam/big.h
index 25466cd3c2..294e1d50fb 100644
--- a/erts/emulator/beam/big.h
+++ b/erts/emulator/beam/big.h
@@ -120,7 +120,7 @@ char *erts_big_to_string(Eterm x, char *buf, Uint buf_sz);
 
 Eterm small_times(Sint, Sint, Eterm*);
 
-Eterm big_plus(Eterm, Eterm, Eterm*);
+Eterm big_plus(Wterm, Wterm, Eterm*);
 Eterm big_minus(Eterm, Eterm, Eterm*);
 Eterm big_times(Eterm, Eterm, Eterm*);
 Eterm big_div(Eterm, Eterm, Eterm*);
@@ -137,9 +137,9 @@ Eterm big_bxor(Eterm, Eterm, Eterm*);
 Eterm big_bnot(Eterm, Eterm*);
 
 Eterm big_lshift(Eterm, Sint, Eterm*);
-int big_comp (Eterm, Eterm);
+int big_comp (Wterm, Wterm);
 int big_ucomp (Eterm, Eterm);
-int big_to_double(Eterm x, double* resp);
+int big_to_double(Wterm x, double* resp);
 Eterm small_to_big(Sint, Eterm*);
 Eterm uint_to_big(Uint, Eterm*);
 Eterm uword_to_big(UWord, Eterm*);
diff --git a/erts/emulator/beam/copy.c b/erts/emulator/beam/copy.c
index 8bee47232e..d582b479cc 100644
--- a/erts/emulator/beam/copy.c
+++ b/erts/emulator/beam/copy.c
@@ -72,8 +72,11 @@ copy_object(Eterm obj, Process* to)
  * Return the "flat" size of the object.
  */
 
-Uint
-size_object(Eterm obj)
+#if HALFWORD_HEAP
+Uint size_object_rel(Eterm obj, Eterm* base)
+#else
+Uint size_object(Eterm obj)
+#endif
 {
     Uint sum = 0;
     Eterm* ptr;
@@ -84,7 +87,7 @@ size_object(Eterm obj)
 	switch (primary_tag(obj)) {
 	case TAG_PRIMARY_LIST:
 	    sum += 2;
-	    ptr = list_val(obj);
+	    ptr = list_val_rel(obj,base);
 	    obj = *ptr++;
 	    if (!IS_CONST(obj)) {
 		ESTACK_PUSH(s, obj);
@@ -93,11 +96,11 @@ size_object(Eterm obj)
 	    break;
 	case TAG_PRIMARY_BOXED:
 	    {
-		Eterm hdr = *boxed_val(obj);
+		Eterm hdr = *boxed_val_rel(obj,base);
 		ASSERT(is_header(hdr));
 		switch (hdr & _TAG_HEADER_MASK) {
 		case ARITYVAL_SUBTAG:
-		    ptr = tuple_val(obj);
+		    ptr = tuple_val_rel(obj,base);
 		    arity = header_arity(hdr);
 		    sum += arity + 1;
 		    if (arity == 0) { /* Empty tuple -- unusual. */
@@ -113,7 +116,7 @@ size_object(Eterm obj)
 		    break;
 		case FUN_SUBTAG:
 		    {
-			Eterm* bptr = fun_val(obj);
+			Eterm* bptr = fun_val_rel(obj,base);
 			ErlFunThing* funp = (ErlFunThing *) bptr;
 			unsigned eterms = 1 /* creator */ + funp->num_free;
 			unsigned sz = thing_arityval(hdr);
@@ -136,7 +139,7 @@ size_object(Eterm obj)
 			Uint bitoffs;
 			Uint extra_bytes;
 			Eterm hdr;
-			ERTS_GET_REAL_BIN(obj, real_bin, offset, bitoffs, bitsize);
+			ERTS_GET_REAL_BIN_REL(obj, real_bin, offset, bitoffs, bitsize, base);
 			if ((bitsize + bitoffs) > 8) {
 			    sum += ERL_SUB_BIN_SIZE;
 			    extra_bytes = 2;
@@ -146,11 +149,11 @@ size_object(Eterm obj)
 			} else {
 			    extra_bytes = 0;
 			}
-			hdr = *binary_val(real_bin);
+			hdr = *binary_val_rel(real_bin,base);
 			if (thing_subtag(hdr) == REFC_BINARY_SUBTAG) {
 			    sum += PROC_BIN_SIZE;
 			} else {
-			    sum += heap_bin_size(binary_size(obj)+extra_bytes);
+			    sum += heap_bin_size(binary_size_rel(obj,base)+extra_bytes);
 			}
 			goto pop_next;
 		    }
@@ -181,8 +184,12 @@ size_object(Eterm obj)
 /*
  *  Copy a structure to a heap.
  */
-Eterm
-copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
+#if HALFWORD_HEAP
+Eterm copy_struct_rel(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap,
+                      Eterm* src_base, Eterm* dst_base)
+#else
+Eterm copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
+#endif
 {
     char* hstart;
     Uint hsize;
@@ -214,7 +221,10 @@ copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 
     /* Copy the object onto the heap */
     switch (primary_tag(obj)) {
-    case TAG_PRIMARY_LIST: argp = &res; goto L_copy_list;
+    case TAG_PRIMARY_LIST:
+	argp = &res;
+	objp = list_val_rel(obj,src_base);
+	goto L_copy_list;
     case TAG_PRIMARY_BOXED: argp = &res; goto L_copy_boxed;
     default:
 	erl_exit(ERTS_ABORT_EXIT,
@@ -231,32 +241,46 @@ copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 	    hp++;
 	    break;
 	case TAG_PRIMARY_LIST:
-	    objp = list_val(obj);
+	    objp = list_val_rel(obj,src_base);
+	#if !HALFWORD_HEAP || defined(DEBUG)
 	    if (in_area(objp,hstart,hsize)) {
+		ASSERT(!HALFWORD_HEAP);
 		hp++;
 		break;
 	    }
+	#endif
 	    argp = hp++;
 	    /* Fall through */
 
 	L_copy_list:
 	    tailp = argp;
-	    while (is_list(obj)) {
-		objp = list_val(obj);
+	    for (;;) {
 		tp = tailp;
-		elem = *objp;
+		elem = CAR(objp);
 		if (IS_CONST(elem)) {
-		    *(hbot-2) = elem;
-		    tailp = hbot-1;
 		    hbot -= 2;
+		    CAR(hbot) = elem;
+		    tailp = &CDR(hbot);
 		}
 		else {
-		    *htop = elem;
-		    tailp = htop+1;
+		    CAR(htop) = elem;
+		#if HALFWORD_HEAP
+		    CDR(htop) = CDR(objp);
+		    *tailp = make_list_rel(htop,dst_base);
+		    htop += 2;
+		    goto L_copy;
+		#else
+		    tailp = &CDR(htop);
 		    htop += 2;
+		#endif
+		}
+		ASSERT(!HALFWORD_HEAP || tp < hp || tp >= hbot);
+		*tp = make_list_rel(tailp - 1, dst_base);
+		obj = CDR(objp);
+		if (!is_list(obj)) {
+		    break;
 		}
-		*tp = make_list(tailp - 1);
-		obj = *(objp+1);
+		objp = list_val_rel(obj,src_base);
 	    }
 	    switch (primary_tag(obj)) {
 	    case TAG_PRIMARY_IMMED1: *tailp = obj; goto L_copy;
@@ -268,21 +292,24 @@ copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 	    }
 	    
 	case TAG_PRIMARY_BOXED:
-	    if (in_area(boxed_val(obj),hstart,hsize)) {
+	#if !HALFWORD_HEAP || defined(DEBUG)
+	    if (in_area(boxed_val_rel(obj,src_base),hstart,hsize)) {
+		ASSERT(!HALFWORD_HEAP);
 		hp++;
 		break;
 	    }
+	#endif
 	    argp = hp++;
 
 	L_copy_boxed:
-	    objp = boxed_val(obj);
+	    objp = boxed_val_rel(obj, src_base);
 	    hdr = *objp;
 	    switch (hdr & _TAG_HEADER_MASK) {
 	    case ARITYVAL_SUBTAG:
 		{
 		    int const_flag = 1; /* assume constant tuple */
 		    i = arityval(hdr);
-		    *argp = make_tuple(htop);
+		    *argp = make_tuple_rel(htop, dst_base);
 		    tp = htop;	/* tp is pointer to new arity value */
 		    *htop++ = *objp++; /* copy arity value */
 		    while (i--) {
@@ -311,7 +338,7 @@ copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 		    while (i--)  {
 			*tp++ = *objp++;
 		    }
-		    *argp = make_binary(hbot);
+		    *argp = make_binary_rel(hbot, dst_base);
 		    pb = (ProcBin*) hbot;
 		    erts_refc_inc(&pb->val->refc, 2);
 		    pb->next = off_heap->first;
@@ -338,7 +365,7 @@ copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 			extra_bytes = 0;
 		    } 
 		    real_size = size+extra_bytes;
-		    objp = binary_val(real_bin);
+		    objp = binary_val_rel(real_bin,src_base);
 		    if (thing_subtag(*objp) == HEAP_BINARY_SUBTAG) {
 			ErlHeapBin* from = (ErlHeapBin *) objp;
 			ErlHeapBin* to;
@@ -368,7 +395,7 @@ copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 			off_heap->first = (struct erl_off_heap_header*) to;
 			OH_OVERHEAD(off_heap, to->size / sizeof(Eterm));
 		    }
-		    *argp = make_binary(hbot);
+		    *argp = make_binary_rel(hbot, dst_base);
 		    if (extra_bytes != 0) {
 			ErlSubBin* res;
 			hbot -= ERL_SUB_BIN_SIZE;
@@ -380,7 +407,7 @@ copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 			res->offs = 0;
 			res->is_writable = 0;
 			res->orig = *argp;
-			*argp = make_binary(hbot);
+			*argp = make_binary_rel(hbot, dst_base);
 		    }
 		    break;
 		}
@@ -400,7 +427,7 @@ copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 		    off_heap->first = (struct erl_off_heap_header*) funp;
 		    erts_refc_inc(&funp->fe->refc, 2);
 #endif
-		    *argp = make_fun(tp);
+		    *argp = make_fun_rel(tp, dst_base);
 		}
 		break;
 	    case EXTERNAL_PID_SUBTAG:
@@ -420,7 +447,7 @@ copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 		  off_heap->first = (struct erl_off_heap_header*)etp;
 		  erts_refc_inc(&etp->node->refc, 2);
 
-		  *argp = make_external(tp);
+		  *argp = make_external_rel(tp, dst_base);
 		}
 		break;
 	    case BIN_MATCHSTATE_SUBTAG:
@@ -430,7 +457,7 @@ copy_struct(Eterm obj, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 		i = thing_arityval(hdr)+1;
 		hbot -= i;
 		tp = hbot;
-		*argp = make_boxed(hbot);
+		*argp = make_boxed_rel(hbot, dst_base);
 		while (i--) {
 		    *tp++ = *objp++;
 		}
@@ -885,12 +912,21 @@ Eterm copy_struct_lazy(Process *from, Eterm orig, Uint offs)
  *
  * 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)
+#if HALFWORD_HEAP
+Eterm copy_shallow_rel(Eterm* ptr, Uint sz, Eterm** hpp, ErlOffHeap* off_heap,
+		       Eterm* src_base)
+#else
+Eterm copy_shallow(Eterm* ptr, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
+#endif
 {
     Eterm* tp = ptr;
     Eterm* hp = *hpp;
-    Sint offs = hp - tp;
+    const Eterm res = make_tuple(hp);
+#if HALFWORD_HEAP
+    const Sint offs = COMPRESS_POINTER(hp - (tp - src_base));
+#else
+    const Sint offs = (hp - tp) * sizeof(Eterm);
+#endif
 
     while (sz--) {
 	Eterm val = *tp++;
@@ -901,7 +937,7 @@ copy_shallow(Eterm* ptr, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 	    break;
 	case TAG_PRIMARY_LIST:
 	case TAG_PRIMARY_BOXED:
-	    *hp++ = offset_ptr(val, offs);
+	    *hp++ = byte_offset_ptr(val, offs);
 	    break;
 	case TAG_PRIMARY_HEADER:
 	    *hp++ = val;
@@ -958,7 +994,8 @@ copy_shallow(Eterm* ptr, Uint sz, Eterm** hpp, ErlOffHeap* off_heap)
 	}
     }
     *hpp = hp;
-    return make_tuple(ptr + offs); 
+
+    return res;
 }
 
 /* Move all terms in heap fragments into heap. The terms must be guaranteed to 
diff --git a/erts/emulator/beam/erl_bif_lists.c b/erts/emulator/beam/erl_bif_lists.c
index ce13469801..d4dc3867ad 100644
--- a/erts/emulator/beam/erl_bif_lists.c
+++ b/erts/emulator/beam/erl_bif_lists.c
@@ -378,7 +378,7 @@ keyfind(int Bif, Process* p, Eterm Key, Eterm Pos, Eterm List)
 		Eterm *tuple_ptr = tuple_val(term);
 		if (pos <= arityval(*tuple_ptr)) {
 		    Eterm element = tuple_ptr[pos];
-		    if (cmp(Key, element) == 0) {
+		    if (CMP(Key, element) == 0) {
 			return term;
 		    }
 		}
diff --git a/erts/emulator/beam/erl_binary.h b/erts/emulator/beam/erl_binary.h
index bdf0fe23fc..3093fb8856 100644
--- a/erts/emulator/beam/erl_binary.h
+++ b/erts/emulator/beam/erl_binary.h
@@ -71,6 +71,7 @@ typedef struct erl_heap_bin {
  */
 
 #define binary_size(Bin) (binary_val(Bin)[1])
+#define binary_size_rel(Bin,BasePtr) (binary_val_rel(Bin,BasePtr)[1])
 
 #define binary_bitsize(Bin)			\
   ((*binary_val(Bin) == HEADER_SUB_BIN) ?	\
@@ -93,9 +94,12 @@ typedef struct erl_heap_bin {
  * Bitsize: output variable (Uint)
  */
 
-#define ERTS_GET_BINARY_BYTES(Bin,Bytep,Bitoffs,Bitsize)		\
+#define ERTS_GET_BINARY_BYTES(Bin,Bytep,Bitoffs,Bitsize) \
+     ERTS_GET_BINARY_BYTES_REL(Bin,Bytep,Bitoffs,Bitsize,NULL)
+
+#define ERTS_GET_BINARY_BYTES_REL(Bin,Bytep,Bitoffs,Bitsize,BasePtr)    \
 do {									\
-    Eterm* _real_bin = binary_val(Bin);					\
+    Eterm* _real_bin = binary_val_rel(Bin,BasePtr);			\
     Uint _offs = 0;							\
     Bitoffs = Bitsize = 0;						\
     if (*_real_bin == HEADER_SUB_BIN) {					\
@@ -103,7 +107,7 @@ do {									\
 	_offs = _sb->offs;						\
         Bitoffs = _sb->bitoffs;						\
         Bitsize = _sb->bitsize;						\
-	_real_bin = binary_val(_sb->orig);				\
+	_real_bin = binary_val_rel(_sb->orig,BasePtr);			\
     }									\
     if (*_real_bin == HEADER_PROC_BIN) {				\
 	Bytep = ((ProcBin *) _real_bin)->bytes + _offs;			\
@@ -125,9 +129,12 @@ do {									\
  * BitSize: Extra bit size (Uint)
  */
 
-#define ERTS_GET_REAL_BIN(Bin, RealBin, ByteOffset, BitOffset, BitSize)	\
+#define ERTS_GET_REAL_BIN(Bin, RealBin, ByteOffset, BitOffset, BitSize) \
+     ERTS_GET_REAL_BIN_REL(Bin, RealBin, ByteOffset, BitOffset, BitSize, NULL)
+
+#define ERTS_GET_REAL_BIN_REL(Bin, RealBin, ByteOffset, BitOffset, BitSize, BasePtr) \
   do {									\
-    ErlSubBin* _sb = (ErlSubBin *) binary_val(Bin);			\
+    ErlSubBin* _sb = (ErlSubBin *) binary_val_rel(Bin,BasePtr);	        \
     if (_sb->thing_word == HEADER_SUB_BIN) {				\
       RealBin = _sb->orig;						\
       ByteOffset = _sb->offs;						\
diff --git a/erts/emulator/beam/erl_db.c b/erts/emulator/beam/erl_db.c
index 3173d3510e..3115e647af 100644
--- a/erts/emulator/beam/erl_db.c
+++ b/erts/emulator/beam/erl_db.c
@@ -910,7 +910,8 @@ BIF_RETTYPE ets_update_counter_3(BIF_ALIST_3)
 	Eterm upop;
 	Eterm* tpl;
 	Sint position;
-	Eterm incr, warp, oldcnt;
+	Eterm incr, warp;
+	Wterm oldcnt;
 
 	if (is_not_list(iter)) {
 	    goto finalize;
@@ -985,7 +986,7 @@ BIF_RETTYPE ets_update_counter_3(BIF_ALIST_3)
 	Eterm* tpl = tuple_val(CAR(list_val(iter)));
 	Sint position = signed_val(tpl[1]);
 	Eterm incr = tpl[2];
-	Eterm oldcnt = handle.dbterm->tpl[position];
+	Wterm oldcnt = db_do_read_element(&handle,position);
 	Eterm newcnt = db_add_counter(&htop, oldcnt, incr);
 
 	if (newcnt == NIL) {
@@ -998,9 +999,9 @@ BIF_RETTYPE ets_update_counter_3(BIF_ALIST_3)
 
 	if (arityval(*tpl) == 4) { /* Maybe warp it */
 	    Eterm threshold = tpl[3];
-	    if ((cmp(incr,make_small(0)) < 0) ? /* negative increment? */
-		(cmp(newcnt,threshold) < 0) :  /* if negative, check if below */
-		(cmp(newcnt,threshold) > 0)) { /* else check if above threshold */
+	    if ((CMP(incr,make_small(0)) < 0) ? /* negative increment? */
+		(CMP(newcnt,threshold) < 0) :  /* if negative, check if below */
+		(CMP(newcnt,threshold) > 0)) { /* else check if above threshold */
 
 		newcnt = tpl[4];
 	    }
@@ -3490,11 +3491,25 @@ static void set_heir(Process* me, DbTable* tb, Eterm heir, UWord heir_data)
 
     if (!is_immed(heir_data)) {
 	DeclareTmpHeap(tmp,2,me);
+	Eterm wrap_tpl;
+	int size;
+	DbTerm* dbterm;
+	Eterm* top;
+	ErlOffHeap tmp_offheap;
 
 	UseTmpHeap(2,me);
-	/* Make a dummy 1-tuple around data to use db_get_term() */
-	heir_data = (UWord) db_store_term(&tb->common, NULL, 0,
-					  TUPLE1(tmp,heir_data));
+	/* Make a dummy 1-tuple around data to use DbTerm */
+	wrap_tpl = TUPLE1(tmp,heir_data);
+	size = size_object(wrap_tpl);
+	// SVERK: Must be low memory
+	dbterm = erts_db_alloc(ERTS_ALC_T_DB_TERM, (DbTable *)tb,
+			       (sizeof(DbTerm) + sizeof(Eterm)*(size-1)));
+	dbterm->size = size;
+	top = dbterm->tpl;
+	tmp_offheap.first  = NULL;
+	copy_struct(wrap_tpl, size, &top, &tmp_offheap);
+	dbterm->first_oh = tmp_offheap.first;
+	heir_data = (UWord)dbterm;
 	UnUseTmpHeap(2,me);
 	ASSERT(!is_immed(heir_data));
     }
diff --git a/erts/emulator/beam/erl_db_hash.c b/erts/emulator/beam/erl_db_hash.c
index 1e50fee554..ced6629c43 100644
--- a/erts/emulator/beam/erl_db_hash.c
+++ b/erts/emulator/beam/erl_db_hash.c
@@ -258,12 +258,6 @@ static ERTS_INLINE Sint next_slot_w(DbTableHash* tb, Uint ix,
 }
 
 
-/* 
- * tplp is an untagged pointer to a tuple we know is large enough 
- * and dth is a pointer to a DbTableHash.   
- */
-#define GETKEY(dth, tplp)   (*((tplp) +  (dth)->common.keypos))
-
 /*
  * Some special binary flags
  */
@@ -434,6 +428,9 @@ static ERTS_INLINE void try_shrink(DbTableHash* tb)
     }
 }	
 
+#define EQ_REL(x,y,y_base) \
+    (is_same(x,NULL,y,y_base) || (is_not_both_immed((x),(y)) && eq_rel((x),(y),y_base)))
+
 /* Is this a live object (not pseodo-deleted) with the specified key? 
 */
 static ERTS_INLINE int has_live_key(DbTableHash* tb, HashDbTerm* b,
@@ -443,7 +440,7 @@ static ERTS_INLINE int has_live_key(DbTableHash* tb, HashDbTerm* b,
     else {
 	Eterm itemKey = GETKEY(tb, b->dbterm.tpl);
 	ASSERT(!is_header(itemKey));
-	return EQ(key,itemKey);
+	return EQ_REL(key, itemKey, b->dbterm.tpl);
     }
 }
 
@@ -456,7 +453,7 @@ static ERTS_INLINE int has_key(DbTableHash* tb, HashDbTerm* b,
     else {
 	Eterm itemKey = GETKEY(tb, b->dbterm.tpl);
 	ASSERT(!is_header(itemKey));
-	return EQ(key,itemKey);
+	return EQ_REL(key, itemKey, b->dbterm.tpl);
     }
 }
 
@@ -696,9 +693,7 @@ static int db_first_hash(Process *p, DbTable *tbl, Eterm *ret)
 	}
     }
     if (list != NULL) {
-	Eterm key = GETKEY(tb, list->dbterm.tpl);
-	
-	COPY_OBJECT(key, p, ret);
+	*ret = db_copy_key(p, tbl, &list->dbterm);
 	RUNLOCK_HASH(lck);
     }
     else {
@@ -746,7 +741,7 @@ static int db_next_hash(Process *p, DbTable *tbl, Eterm key, Eterm *ret)
 	*ret = am_EOT;
     }
     else {
-	COPY_OBJECT(GETKEY(tb, b->dbterm.tpl), p, ret);
+	*ret = db_copy_key(p, tbl, &b->dbterm);
 	RUNLOCK_HASH(lck);
     }    
     return DB_ERROR_NONE;
@@ -2695,6 +2690,9 @@ static int db_lookup_dbterm_hash(DbTable *tbl, Eterm key, DbUpdateHandle* handle
 	    handle->dbterm = &b->dbterm;
 	    handle->mustResize = 0;
 	    handle->new_size = b->dbterm.size;
+	    #if HALFWORD_HEAP
+	    handle->new_tuple = handle->dbterm->tpl;
+	    #endif
 	    handle->lck = lck;
 	    /* KEEP hval WLOCKED, db_finalize_dbterm_hash will WUNLOCK */
 	    return 1;
diff --git a/erts/emulator/beam/erl_db_tree.c b/erts/emulator/beam/erl_db_tree.c
index 8108494fc5..c74ccdc119 100644
--- a/erts/emulator/beam/erl_db_tree.c
+++ b/erts/emulator/beam/erl_db_tree.c
@@ -48,9 +48,6 @@
 
 #include "erl_db_tree.h"
 
-
-
-#define GETKEY(dtt, tplp)   (*((tplp) +  (dtt)->common.keypos))
 #define GETKEY_WITH_POS(Keypos, Tplp) (*((Tplp) + Keypos))
 #define NITEMS(tb) ((int)erts_smp_atomic_read(&(tb)->common.nitems))
 
@@ -282,7 +279,7 @@ struct select_delete_context {
 /*
 ** Forward declarations 
 */
-static TreeDbTerm *linkout_tree(DbTableTree *tb, Eterm key);
+static TreeDbTerm *linkout_tree(DbTableTree *tb, Eterm key, Eterm* key_base);
 static TreeDbTerm *linkout_object_tree(DbTableTree *tb, 
 				       Eterm object);
 static int do_free_tree_cont(DbTableTree *tb, int num_left);
@@ -293,15 +290,15 @@ static int delsub(TreeDbTerm **this);
 static TreeDbTerm *slot_search(Process *p, DbTableTree *tb, Sint slot);
 static TreeDbTerm *find_node(DbTableTree *tb, Eterm key);
 static TreeDbTerm **find_node2(DbTableTree *tb, Eterm key);
-static TreeDbTerm *find_next(DbTableTree *tb, DbTreeStack*, Eterm key);
-static TreeDbTerm *find_prev(DbTableTree *tb, DbTreeStack*, Eterm key);
+static TreeDbTerm *find_next(DbTableTree *tb, DbTreeStack*, Eterm key, Eterm* kbase);
+static TreeDbTerm *find_prev(DbTableTree *tb, DbTreeStack*, Eterm key, Eterm* kbase);
 static TreeDbTerm *find_next_from_pb_key(DbTableTree *tb, DbTreeStack*,
 					 Eterm key);
 static TreeDbTerm *find_prev_from_pb_key(DbTableTree *tb, DbTreeStack*,
 					 Eterm key);
 static void traverse_backwards(DbTableTree *tb,
 			       DbTreeStack*,
-			       Eterm lastkey,
+			       Eterm lastkey, Eterm* lk_base,
 			       int (*doit)(DbTableTree *tb,
 					   TreeDbTerm *,
 					   void *,
@@ -309,7 +306,7 @@ static void traverse_backwards(DbTableTree *tb,
 			       void *context); 
 static void traverse_forward(DbTableTree *tb,
 			     DbTreeStack*,
-			     Eterm lastkey,
+			     Eterm lastkey, Eterm* lk_base,
 			     int (*doit)(DbTableTree *tb,
 					 TreeDbTerm *,
 					 void *,
@@ -317,8 +314,8 @@ static void traverse_forward(DbTableTree *tb,
 			     void *context); 
 static int key_given(DbTableTree *tb, Eterm pattern, TreeDbTerm **ret,
 		     Eterm *partly_bound_key);
-static Sint cmp_partly_bound(Eterm partly_bound_key, Eterm bound_key);
-static Sint do_cmp_partly_bound(Eterm a, Eterm b, int *done);
+static Sint cmp_partly_bound(Eterm partly_bound_key, Eterm bound_key, Eterm* bk_base);
+static Sint do_cmp_partly_bound(Eterm a, Eterm b, Eterm* b_base, int *done);
 
 static int analyze_pattern(DbTableTree *tb, Eterm pattern, 
 			   struct mp_info *mpi);
@@ -492,9 +489,6 @@ static int db_first_tree(Process *p, DbTable *tbl, Eterm *ret)
     DbTableTree *tb = &tbl->tree;
     DbTreeStack* stack;
     TreeDbTerm *this;
-    Eterm e;
-    Eterm *hp;
-    Uint sz;
 
     if (( this = tb->root ) == NULL) {
 	*ret = am_EOT;
@@ -513,13 +507,7 @@ static int db_first_tree(Process *p, DbTable *tbl, Eterm *ret)
 	stack->slot = 1;
 	release_stack(tb,stack);
     }
-    e = GETKEY(tb, this->dbterm.tpl);
-    sz = size_object(e);
-
-    hp = HAlloc(p, sz);
-
-    *ret = copy_struct(e,sz,&hp,&MSO(p));
-    
+    *ret = db_copy_key(p, tbl, &this->dbterm);
     return DB_ERROR_NONE;
 }
 
@@ -528,26 +516,17 @@ static int db_next_tree(Process *p, DbTable *tbl, Eterm key, Eterm *ret)
     DbTableTree *tb = &tbl->tree;
     DbTreeStack* stack;
     TreeDbTerm *this;
-    Eterm e;
-    Eterm *hp;
-    Uint sz;
 
     if (is_atom(key) && key == am_EOT)
 	return DB_ERROR_BADKEY;
     stack = get_any_stack(tb);
-    this = find_next(tb, stack, key);
+    this = find_next(tb, stack, key, NULL);
     release_stack(tb,stack);
     if (this == NULL) {
 	*ret = am_EOT;
 	return DB_ERROR_NONE;
     }
-    e = GETKEY(tb, this->dbterm.tpl);
-    sz = size_object(e);
-
-    hp = HAlloc(p, sz);
-
-    *ret = copy_struct(e,sz,&hp,&MSO(p));
-    
+    *ret = db_copy_key(p, tbl, &this->dbterm);
     return DB_ERROR_NONE;
 }
 
@@ -556,9 +535,6 @@ static int db_last_tree(Process *p, DbTable *tbl, Eterm *ret)
     DbTableTree *tb = &tbl->tree;
     TreeDbTerm *this;
     DbTreeStack* stack;
-    Eterm e;
-    Eterm *hp;
-    Uint sz;
 
     if (( this = tb->root ) == NULL) {
 	*ret = am_EOT;
@@ -577,13 +553,7 @@ static int db_last_tree(Process *p, DbTable *tbl, Eterm *ret)
 	stack->slot = NITEMS(tb);
 	release_stack(tb,stack);
     }
-    e = GETKEY(tb, this->dbterm.tpl);
-    sz = size_object(e);
-
-    hp = HAlloc(p, sz);
-
-    *ret = copy_struct(e,sz,&hp,&MSO(p));
-    
+    *ret = db_copy_key(p, tbl, &this->dbterm);
     return DB_ERROR_NONE;
 }
 
@@ -592,27 +562,33 @@ static int db_prev_tree(Process *p, DbTable *tbl, Eterm key, Eterm *ret)
     DbTableTree *tb = &tbl->tree;
     TreeDbTerm *this;
     DbTreeStack* stack;
-    Eterm e;
-    Eterm *hp;
-    Uint sz;
 
     if (is_atom(key) && key == am_EOT)
 	return DB_ERROR_BADKEY;
     stack = get_any_stack(tb);
-    this = find_prev(tb, stack, key);
+    this = find_prev(tb, stack, key, NULL);
     release_stack(tb,stack);
     if (this == NULL) {
 	*ret = am_EOT;
 	return DB_ERROR_NONE;
     }
-    e = GETKEY(tb, this->dbterm.tpl);
-    sz = size_object(e);
+    *ret = db_copy_key(p, tbl, &this->dbterm);
+    return DB_ERROR_NONE;
+}
 
-    hp = HAlloc(p, sz);
+static ERTS_INLINE int cmp_key(DbTableTree* tb, Eterm key, Eterm* key_base,
+			       TreeDbTerm* obj)
+{
+    return cmp_rel(key, key_base,
+		   GETKEY(tb,obj->dbterm.tpl), obj->dbterm.tpl);
+}
 
-    *ret = copy_struct(e,sz,&hp,&MSO(p));
-    
-    return DB_ERROR_NONE;
+static ERTS_INLINE int cmp_key_eq(DbTableTree* tb, Eterm key, Eterm* key_base,
+				  TreeDbTerm* obj)
+{
+    Eterm obj_key = GETKEY(tb,obj->dbterm.tpl);
+    return is_same(key, key_base, obj_key, obj->dbterm.tpl)
+	|| cmp_rel(key, key_base, obj_key, obj->dbterm.tpl) == 0;
 }
 
 static int db_put_tree(DbTable *tbl, Eterm obj, int key_clash_fail)
@@ -646,8 +622,8 @@ static int db_put_tree(DbTable *tbl, Eterm obj, int key_clash_fail)
 	    (*this)->balance = 0;
 	    (*this)->left = (*this)->right = NULL;
 	    break;
-	} else if ((c = cmp(key,GETKEY(tb,(*this)->dbterm.tpl))) < 0) { 
-	    /* go left */
+	} else if ((c = cmp_key(tb, key, NULL, *this)) < 0) {
+	    /* go lefts */
 	    dstack[dpos++] = DIR_LEFT;
 	    tstack[tpos++] = this;
 	    this = &((*this)->left);
@@ -801,7 +777,7 @@ static int db_erase_tree(DbTable *tbl, Eterm key, Eterm *ret)
 
     *ret = am_true;
 
-    if ((res = linkout_tree(tb, key)) != NULL) {
+    if ((res = linkout_tree(tb, key, NULL)) != NULL) {
 	free_term(tb, res);
     }
     return DB_ERROR_NONE;
@@ -993,15 +969,15 @@ static int db_select_continue_tree(Process *p,
     stack = get_any_stack(tb);
     if (chunk_size) {
 	if (reverse) {
-	    traverse_backwards(tb, stack, lastkey, &doit_select_chunk, &sc); 
+	    traverse_backwards(tb, stack, lastkey, NULL, &doit_select_chunk, &sc);
 	} else {
-	    traverse_forward(tb, stack, lastkey, &doit_select_chunk, &sc); 
+	    traverse_forward(tb, stack, lastkey, NULL, &doit_select_chunk, &sc);
 	}
     } else {
 	if (reverse) {
-	    traverse_forward(tb, stack, lastkey, &doit_select, &sc);
+	    traverse_forward(tb, stack, lastkey, NULL, &doit_select, &sc);
 	} else {
-	    traverse_backwards(tb, stack, lastkey, &doit_select, &sc);
+	    traverse_backwards(tb, stack, lastkey, NULL, &doit_select, &sc);
 	}
     }
     release_stack(tb,stack);
@@ -1026,10 +1002,9 @@ static int db_select_continue_tree(Process *p,
 	    }
 
 	    key = GETKEY(tb, sc.lastobj);
-
-	    sz = size_object(key);
+	    sz = size_object_rel(key,sc.lastobj);
 	    hp = HAlloc(p, 9 + sz);
-	    key = copy_struct(key, sz, &hp, &MSO(p));
+	    key = copy_struct_rel(key, sz, &hp, &MSO(p), sc.lastobj, NULL);
 	    continuation = TUPLE8
 		(hp,
 		 tptr[1],
@@ -1050,8 +1025,8 @@ static int db_select_continue_tree(Process *p,
     key = GETKEY(tb, sc.lastobj);
     if (chunk_size) {
 	if (end_condition != NIL && 
-	    ((!reverse && cmp_partly_bound(end_condition,key) < 0) ||
-	     (reverse && cmp_partly_bound(end_condition,key) > 0))) { 
+	    ((!reverse && cmp_partly_bound(end_condition,key,sc.lastobj) < 0) ||
+	     (reverse && cmp_partly_bound(end_condition,key,sc.lastobj) > 0))) {
 	    /* done anyway */
 	    if (!sc.got) {
 		RET_TO_BIF(am_EOT, DB_ERROR_NONE);
@@ -1063,16 +1038,16 @@ static int db_select_continue_tree(Process *p,
 	}
     } else {
 	if (end_condition != NIL && 
-	    ((!reverse && cmp_partly_bound(end_condition,key) > 0) ||
-	     (reverse && cmp_partly_bound(end_condition,key) < 0))) { 
+	    ((!reverse && cmp_partly_bound(end_condition,key,sc.lastobj) > 0) ||
+	     (reverse && cmp_partly_bound(end_condition,key,sc.lastobj) < 0))) {
 	    /* done anyway */
 	    RET_TO_BIF(sc.accum,DB_ERROR_NONE);
 	}
     }
     /* Not done yet, let's trap. */
-    sz = size_object(key);
+    sz = size_object_rel(key,sc.lastobj);
     hp = HAlloc(p, 9 + sz);
-    key = copy_struct(key, sz, &hp, &MSO(p));
+    key = copy_struct_rel(key, sz, &hp, &MSO(p), sc.lastobj, NULL);
     continuation = TUPLE8
 	(hp,
 	 tptr[1],
@@ -1099,6 +1074,7 @@ static int db_select_tree(Process *p, DbTable *tbl,
     struct select_context sc;
     struct mp_info mpi;
     Eterm lastkey = THE_NON_VALUE;
+    Eterm* lk_base = NULL;
     Eterm key;
     Eterm continuation;
     unsigned sz;
@@ -1140,7 +1116,7 @@ static int db_select_tree(Process *p, DbTable *tbl,
     sc.all_objects = mpi.all_objects;
 
     if (!mpi.got_partial && mpi.some_limitation && 
-	cmp(mpi.least,mpi.most) == 0) {
+	CMP(mpi.least,mpi.most) == 0) {
 	doit_select(tb,mpi.save_term,&sc,0 /* direction doesn't matter */);
 	RET_TO_BIF(sc.accum,DB_ERROR_NONE);
     }
@@ -1150,20 +1126,20 @@ static int db_select_tree(Process *p, DbTable *tbl,
 	if (mpi.some_limitation) {
 	    if ((this = find_prev_from_pb_key(tb, stack, mpi.least)) != NULL) {
 		lastkey = GETKEY(tb, this->dbterm.tpl);
+		lk_base = this->dbterm.tpl;
 	    }
 	    sc.end_condition = mpi.most;
 	}
-	
-	traverse_forward(tb, stack, lastkey, &doit_select, &sc);
+	traverse_forward(tb, stack, lastkey, lk_base, &doit_select, &sc);
     } else {
 	if (mpi.some_limitation) {
 	    if ((this = find_next_from_pb_key(tb, stack, mpi.most)) != NULL) {
 		lastkey = GETKEY(tb, this->dbterm.tpl);
+		lk_base = this->dbterm.tpl;
 	    }
 	    sc.end_condition = mpi.least;
 	}
-	
-	traverse_backwards(tb, stack, lastkey, &doit_select, &sc);
+	traverse_backwards(tb, stack, lastkey, lk_base, &doit_select, &sc);
     }
     release_stack(tb,stack);
 #ifdef HARDDEBUG
@@ -1176,9 +1152,9 @@ static int db_select_tree(Process *p, DbTable *tbl,
     }
 
     key = GETKEY(tb, sc.lastobj);
-    sz = size_object(key);
+    sz = size_object_rel(key, sc.lastobj);
     hp = HAlloc(p, 9 + sz + PROC_BIN_SIZE);
-    key = copy_struct(key, sz, &hp, &MSO(p));
+    key = copy_struct_rel(key, sz, &hp, &MSO(p), sc.lastobj, NULL);
     if (mpi.all_objects)
 	(mpi.mp)->flags |= BIN_FLAG_ALL_OBJECTS;
     mpb=db_make_mp_binary(p,mpi.mp,&hp);
@@ -1259,7 +1235,7 @@ static int db_select_count_continue_tree(Process *p,
     }
 
     stack = get_any_stack(tb);
-    traverse_backwards(tb, stack, lastkey, &doit_select_count, &sc);
+    traverse_backwards(tb, stack, lastkey, NULL, &doit_select_count, &sc);
     release_stack(tb,stack);
 
     BUMP_REDS(p, 1000 - sc.max);
@@ -1269,12 +1245,12 @@ static int db_select_count_continue_tree(Process *p,
     }	
     key = GETKEY(tb, sc.lastobj);
     if (end_condition != NIL && 
-	(cmp_partly_bound(end_condition,key) > 0)) { 
+	(cmp_partly_bound(end_condition,key,sc.lastobj) > 0)) {
 	/* done anyway */
 	RET_TO_BIF(make_small(sc.got),DB_ERROR_NONE);
     }
     /* Not done yet, let's trap. */
-    sz = size_object(key);
+    sz = size_object_rel(key, sc.lastobj);
     if (IS_USMALL(0, sc.got)) {
 	hp = HAlloc(p, sz + 6);
 	egot = make_small(sc.got);
@@ -1284,7 +1260,7 @@ static int db_select_count_continue_tree(Process *p,
 	egot = uint_to_big(sc.got, hp);
 	hp += BIG_UINT_HEAP_SIZE;
     }
-    key = copy_struct(key, sz, &hp, &MSO(p));
+    key = copy_struct_rel(key, sz, &hp, &MSO(p), sc.lastobj, NULL);
     continuation = TUPLE5
 	(hp,
 	 tptr[1],
@@ -1307,6 +1283,7 @@ static int db_select_count_tree(Process *p, DbTable *tbl,
     struct select_count_context sc;
     struct mp_info mpi;
     Eterm lastkey = THE_NON_VALUE;
+    Eterm* lk_base = NULL;
     Eterm key;
     Eterm continuation;
     unsigned sz;
@@ -1347,7 +1324,7 @@ static int db_select_count_tree(Process *p, DbTable *tbl,
     sc.all_objects = mpi.all_objects;
 
     if (!mpi.got_partial && mpi.some_limitation && 
-	cmp(mpi.least,mpi.most) == 0) {
+	CMP(mpi.least,mpi.most) == 0) {
 	doit_select_count(tb,mpi.save_term,&sc,0 /* dummy */);
 	RET_TO_BIF(erts_make_integer(sc.got,p),DB_ERROR_NONE);
     }
@@ -1356,11 +1333,12 @@ static int db_select_count_tree(Process *p, DbTable *tbl,
     if (mpi.some_limitation) {
 	if ((this = find_next_from_pb_key(tb, stack, mpi.most)) != NULL) {
 	    lastkey = GETKEY(tb, this->dbterm.tpl);
+	    lk_base = this->dbterm.tpl;
 	}
 	sc.end_condition = mpi.least;
     }
     
-    traverse_backwards(tb, stack, lastkey, &doit_select_count, &sc);
+    traverse_backwards(tb, stack, lastkey, lk_base, &doit_select_count, &sc);
     release_stack(tb,stack);
     BUMP_REDS(p, 1000 - sc.max);
     if (sc.max > 0) {
@@ -1368,7 +1346,7 @@ static int db_select_count_tree(Process *p, DbTable *tbl,
     }
 
     key = GETKEY(tb, sc.lastobj);
-    sz = size_object(key);
+    sz = size_object_rel(key, sc.lastobj);
     if (IS_USMALL(0, sc.got)) {
 	hp = HAlloc(p, sz + PROC_BIN_SIZE + 6);
 	egot = make_small(sc.got);
@@ -1378,7 +1356,7 @@ static int db_select_count_tree(Process *p, DbTable *tbl,
 	egot = uint_to_big(sc.got, hp);
 	hp += BIG_UINT_HEAP_SIZE;
     }
-    key = copy_struct(key, sz, &hp, &MSO(p));
+    key = copy_struct_rel(key, sz, &hp, &MSO(p), sc.lastobj, NULL);
     if (mpi.all_objects)
 	(mpi.mp)->flags |= BIN_FLAG_ALL_OBJECTS;
     mpb = db_make_mp_binary(p,mpi.mp,&hp);
@@ -1409,6 +1387,7 @@ static int db_select_chunk_tree(Process *p, DbTable *tbl,
     struct select_context sc;
     struct mp_info mpi;
     Eterm lastkey = THE_NON_VALUE;
+    Eterm* lk_base = NULL;
     Eterm key;
     Eterm continuation;
     unsigned sz;
@@ -1450,7 +1429,7 @@ static int db_select_chunk_tree(Process *p, DbTable *tbl,
     sc.all_objects = mpi.all_objects;
 
     if (!mpi.got_partial && mpi.some_limitation && 
-	cmp(mpi.least,mpi.most) == 0) {
+	CMP(mpi.least,mpi.most) == 0) {
 	doit_select(tb,mpi.save_term,&sc, 0 /* direction doesn't matter */);
 	if (sc.accum != NIL) {
 	    hp=HAlloc(p, 3);
@@ -1465,20 +1444,20 @@ static int db_select_chunk_tree(Process *p, DbTable *tbl,
 	if (mpi.some_limitation) {
 	    if ((this = find_next_from_pb_key(tb, stack, mpi.most)) != NULL) {
 		lastkey = GETKEY(tb, this->dbterm.tpl);
+		lk_base = this->dbterm.tpl;
 	    }
 	    sc.end_condition = mpi.least;
 	}
-
-	traverse_backwards(tb, stack, lastkey, &doit_select_chunk, &sc);
+	traverse_backwards(tb, stack, lastkey, lk_base, &doit_select_chunk, &sc);
     } else {
 	if (mpi.some_limitation) {
 	    if ((this = find_prev_from_pb_key(tb, stack, mpi.least)) != NULL) {
 		lastkey = GETKEY(tb, this->dbterm.tpl);
+		lk_base = this->dbterm.tpl;
 	    }
 	    sc.end_condition = mpi.most;
 	}
-
-	traverse_forward(tb, stack, lastkey, &doit_select_chunk, &sc);
+	traverse_forward(tb, stack, lastkey, lk_base, &doit_select_chunk, &sc);
     }
     release_stack(tb,stack);
 
@@ -1503,9 +1482,9 @@ static int db_select_chunk_tree(Process *p, DbTable *tbl,
 	}
 
 	key = GETKEY(tb, sc.lastobj);
-	sz = size_object(key);
+	sz = size_object_rel(key, sc.lastobj);
 	hp = HAlloc(p, 9 + sz + PROC_BIN_SIZE);
-	key = copy_struct(key, sz, &hp, &MSO(p));
+	key = copy_struct_rel(key, sz, &hp, &MSO(p), sc.lastobj, NULL);
 	if (mpi.all_objects)
 	    (mpi.mp)->flags |= BIN_FLAG_ALL_OBJECTS;
 	mpb = db_make_mp_binary(p,mpi.mp,&hp);
@@ -1528,9 +1507,9 @@ static int db_select_chunk_tree(Process *p, DbTable *tbl,
     }
 
     key = GETKEY(tb, sc.lastobj);
-    sz = size_object(key);
+    sz = size_object_rel(key, sc.lastobj);
     hp = HAlloc(p, 9 + sz + PROC_BIN_SIZE);
-    key = copy_struct(key, sz, &hp, &MSO(p));
+    key = copy_struct_rel(key, sz, &hp, &MSO(p), sc.lastobj, NULL);
 
     if (mpi.all_objects)
 	(mpi.mp)->flags |= BIN_FLAG_ALL_OBJECTS;
@@ -1606,7 +1585,7 @@ static int db_select_delete_continue_tree(Process *p,
     sc.keypos = tb->common.keypos;
 
     ASSERT(!erts_smp_atomic_read(&tb->is_stack_busy));
-    traverse_backwards(tb, &tb->static_stack, lastkey, &doit_select_delete, &sc);
+    traverse_backwards(tb, &tb->static_stack, lastkey, NULL, &doit_select_delete, &sc);
 
     BUMP_REDS(p, 1000 - sc.max);
 
@@ -1615,11 +1594,11 @@ static int db_select_delete_continue_tree(Process *p,
     }	
     key = GETKEY(tb, (sc.lastterm)->dbterm.tpl);
     if (end_condition != NIL && 
-	cmp_partly_bound(end_condition,key) > 0) { /* done anyway */
+	cmp_partly_bound(end_condition,key,sc.lastterm->dbterm.tpl) > 0) { /* done anyway */
 	RET_TO_BIF(erts_make_integer(sc.accum,p),DB_ERROR_NONE);
     }
     /* Not done yet, let's trap. */
-    sz = size_object(key);
+    sz = size_object_rel(key, sc.lastterm->dbterm.tpl);
     if (IS_USMALL(0, sc.accum)) {
 	hp = HAlloc(p, sz + 6);
 	eaccsum = make_small(sc.accum);
@@ -1629,7 +1608,7 @@ static int db_select_delete_continue_tree(Process *p,
 	eaccsum = uint_to_big(sc.accum, hp);
 	hp += BIG_UINT_HEAP_SIZE;
     }
-    key = copy_struct(key, sz, &hp, &MSO(p));
+    key = copy_struct_rel(key, sz, &hp, &MSO(p), sc.lastterm->dbterm.tpl, NULL);
     continuation = TUPLE5
 	(hp,
 	 tptr[1],
@@ -1650,6 +1629,7 @@ static int db_select_delete_tree(Process *p, DbTable *tbl,
     struct select_delete_context sc;
     struct mp_info mpi;
     Eterm lastkey = THE_NON_VALUE;
+    Eterm* lk_base = NULL;
     Eterm key;
     Eterm continuation;
     unsigned sz;
@@ -1693,7 +1673,7 @@ static int db_select_delete_tree(Process *p, DbTable *tbl,
     sc.mp = mpi.mp;
 
     if (!mpi.got_partial && mpi.some_limitation && 
-	cmp(mpi.least,mpi.most) == 0) {
+	CMP(mpi.least,mpi.most) == 0) {
 	doit_select_delete(tb,mpi.save_term,&sc, 0 /* direction doesn't 
 						      matter */);
 	RET_TO_BIF(erts_make_integer(sc.accum,p),DB_ERROR_NONE);
@@ -1702,11 +1682,12 @@ static int db_select_delete_tree(Process *p, DbTable *tbl,
     if (mpi.some_limitation) {
 	if ((this = find_next_from_pb_key(tb, &tb->static_stack, mpi.most)) != NULL) {
 	    lastkey = GETKEY(tb, this->dbterm.tpl);
+	    lk_base = this->dbterm.tpl;
 	}
 	sc.end_condition = mpi.least;
     }
 
-    traverse_backwards(tb, &tb->static_stack, lastkey, &doit_select_delete, &sc);
+    traverse_backwards(tb, &tb->static_stack, lastkey, lk_base, &doit_select_delete, &sc);
     BUMP_REDS(p, 1000 - sc.max);
 
     if (sc.max > 0) {
@@ -1714,7 +1695,7 @@ static int db_select_delete_tree(Process *p, DbTable *tbl,
     }
 
     key = GETKEY(tb, (sc.lastterm)->dbterm.tpl);
-    sz = size_object(key);
+    sz = size_object_rel(key, sc.lastterm->dbterm.tpl);
     if (IS_USMALL(0, sc.accum)) {
 	hp = HAlloc(p, sz + PROC_BIN_SIZE + 6);
 	eaccsum = make_small(sc.accum);
@@ -1724,7 +1705,7 @@ static int db_select_delete_tree(Process *p, DbTable *tbl,
 	eaccsum = uint_to_big(sc.accum, hp);
 	hp += BIG_UINT_HEAP_SIZE;
     }
-    key = copy_struct(key, sz, &hp, &MSO(p));
+    key = copy_struct_rel(key, sz, &hp, &MSO(p), sc.lastterm->dbterm.tpl, NULL);
     mpb = db_make_mp_binary(p,mpi.mp,&hp);
     
     continuation = TUPLE5
@@ -1842,7 +1823,7 @@ do_db_tree_foreach_offheap(TreeDbTerm *tdbt,
 }
 
 static TreeDbTerm *linkout_tree(DbTableTree *tb, 
-				Eterm key)
+				Eterm key, Eterm* key_base)
 {
     TreeDbTerm **tstack[STACK_NEED];
     int tpos = 0;
@@ -1865,7 +1846,7 @@ static TreeDbTerm *linkout_tree(DbTableTree *tb,
     for (;;) {
 	if (!*this) { /* Failure */
 	    return NULL;
-	} else if ((c = cmp(key,GETKEY(tb,(*this)->dbterm.tpl))) < 0) { 
+	} else if ((c = cmp_key(tb, key, key_base, *this)) < 0) {
 	    dstack[dpos++] = DIR_LEFT;
 	    tstack[tpos++] = this;
 	    this = &((*this)->left);
@@ -1929,7 +1910,7 @@ static TreeDbTerm *linkout_object_tree(DbTableTree *tb,
     for (;;) {
 	if (!*this) { /* Failure */
 	    return NULL;
-	} else if ((c = cmp(key,GETKEY(tb,(*this)->dbterm.tpl))) < 0) { 
+	} else if ((c = cmp_key(tb,key,NULL,*this)) < 0) {
 	    dstack[dpos++] = DIR_LEFT;
 	    tstack[tpos++] = this;
 	    this = &((*this)->left);
@@ -2324,14 +2305,15 @@ done:
  * Find next and previous in sort order
  */
 
-static TreeDbTerm *find_next(DbTableTree *tb, DbTreeStack* stack, Eterm key)
+static TreeDbTerm *find_next(DbTableTree *tb, DbTreeStack* stack,
+			     Eterm key, Eterm* key_base)
 {
     TreeDbTerm *this;
     TreeDbTerm *tmp;
     Sint c;
 
     if(( this = TOP_NODE(stack)) != NULL) {
-	if (!CMP_EQ(GETKEY(tb, this->dbterm.tpl),key)) {
+	if (!cmp_key_eq(tb,key,key_base,this)) {
 	    /* Start from the beginning */
 	    stack->pos = stack->slot = 0;
 	}
@@ -2341,14 +2323,14 @@ static TreeDbTerm *find_next(DbTableTree *tb, DbTreeStack* stack, Eterm key)
 	    return NULL;
 	for (;;) {
 	    PUSH_NODE(stack, this);
-	    if (( c = cmp(GETKEY(tb, this->dbterm.tpl),key) ) < 0) {
+	    if (( c = cmp_key(tb,key,key_base,this) ) > 0) {
 		if (this->right == NULL) /* We are at the previos 
 					    and the element does
 					    not exist */
 		    break;
 		else
 		    this = this->right;
-	    } else if (c > 0) {
+	    } else if (c < 0) {
 		if (this->left == NULL) /* Done */
 		    return this;
 		else
@@ -2381,14 +2363,15 @@ static TreeDbTerm *find_next(DbTableTree *tb, DbTreeStack* stack, Eterm key)
     return this;
 }
 
-static TreeDbTerm *find_prev(DbTableTree *tb, DbTreeStack* stack, Eterm key)
+static TreeDbTerm *find_prev(DbTableTree *tb, DbTreeStack* stack,
+			     Eterm key, Eterm* key_base)
 {
     TreeDbTerm *this;
     TreeDbTerm *tmp;
     Sint c;
 
     if(( this = TOP_NODE(stack)) != NULL) {
-	if (!CMP_EQ(GETKEY(tb, this->dbterm.tpl),key)) {
+	if (!cmp_key_eq(tb,key,key_base,this)) {
 	    /* Start from the beginning */
 	    stack->pos = stack->slot = 0;
 	}
@@ -2398,14 +2381,14 @@ static TreeDbTerm *find_prev(DbTableTree *tb, DbTreeStack* stack, Eterm key)
 	    return NULL;
 	for (;;) {
 	    PUSH_NODE(stack, this);
-	    if (( c = cmp(GETKEY(tb, this->dbterm.tpl),key) ) > 0) {
+	    if (( c = cmp_key(tb,key,key_base,this) ) < 0) {
 		if (this->left == NULL) /* We are at the next 
 					   and the element does
 					   not exist */
 		    break;
 		else
 		    this = this->left;
-	    } else if (c < 0) {
+	    } else if (c > 0) {
 		if (this->right == NULL) /* Done */
 		    return this;
 		else
@@ -2451,7 +2434,8 @@ static TreeDbTerm *find_next_from_pb_key(DbTableTree *tb, DbTreeStack* stack,
 	return NULL;
     for (;;) {
 	PUSH_NODE(stack, this);
-	if (( c = cmp_partly_bound(key,GETKEY(tb, this->dbterm.tpl)) ) >= 0) {
+	if (( c = cmp_partly_bound(key,GETKEY(tb, this->dbterm.tpl),
+				   this->dbterm.tpl) ) >= 0) {
 	    if (this->right == NULL) {
 		do {
 		    tmp = POP_NODE(stack);
@@ -2484,7 +2468,8 @@ static TreeDbTerm *find_prev_from_pb_key(DbTableTree *tb, DbTreeStack* stack,
 	return NULL;
     for (;;) {
 	PUSH_NODE(stack, this);
-	if (( c = cmp_partly_bound(key,GETKEY(tb, this->dbterm.tpl)) ) <= 0) {
+	if (( c = cmp_partly_bound(key,GETKEY(tb, this->dbterm.tpl),
+				   this->dbterm.tpl) ) <= 0) {
 	    if (this->left == NULL) {
 		do {
 		    tmp = POP_NODE(stack);
@@ -2514,12 +2499,11 @@ static TreeDbTerm *find_node(DbTableTree *tb, Eterm key)
     Sint res;
     DbTreeStack* stack = get_static_stack(tb);
 
-    if(!stack || EMPTY_NODE(stack) 
-       || !CMP_EQ(GETKEY(tb, ( this = TOP_NODE(stack) )->dbterm.tpl), key)) {
+    if(!stack || EMPTY_NODE(stack)
+       || !cmp_key_eq(tb, key, NULL, (this=TOP_NODE(stack)))) {
 
 	this = tb->root;
-	while (this != NULL && 
-	       ( res = cmp(key, GETKEY(tb, this->dbterm.tpl)) ) != 0) {
+	while (this != NULL && (res = cmp_key(tb,key,NULL,this)) != 0) {
 	    if (res < 0)
 		this = this->left;
 	    else
@@ -2541,8 +2525,7 @@ static TreeDbTerm **find_node2(DbTableTree *tb, Eterm key)
     Sint res;
 
     this = &tb->root;
-    while ((*this) != NULL && 
-	   ( res = cmp(key, GETKEY(tb, (*this)->dbterm.tpl)) ) != 0) {
+    while ((*this) != NULL && (res = cmp_key(tb, key, NULL, *this)) != 0) {
 	if (res < 0)
 	    this = &((*this)->left);
 	else
@@ -2565,6 +2548,9 @@ static int db_lookup_dbterm_tree(DbTable *tbl, Eterm key, DbUpdateHandle* handle
     handle->mustResize = 0;
     handle->bp = (void**) pp;
     handle->new_size = (*pp)->dbterm.size;
+    #if HALFWORD_HEAP
+    handle->new_tuple = handle->dbterm->tpl;
+    #endif
     return 1;
 }
 
@@ -2589,7 +2575,7 @@ static void db_finalize_dbterm_tree(DbUpdateHandle* handle)
  */
 static void traverse_backwards(DbTableTree *tb,
 			       DbTreeStack* stack,
-			       Eterm lastkey,
+			       Eterm lastkey, Eterm* lk_base,
 			       int (*doit)(DbTableTree *,
 					   TreeDbTerm *,
 					   void *,
@@ -2608,15 +2594,16 @@ static void traverse_backwards(DbTableTree *tb,
 	    this = this->right;
 	}
 	this = TOP_NODE(stack);
-	next = find_prev(tb, stack, GETKEY(tb, this->dbterm.tpl));
+	next = find_prev(tb, stack, GETKEY(tb, this->dbterm.tpl),
+			 this->dbterm.tpl);
 	if (!((*doit)(tb, this, context, 0)))
 	    return;
     } else {
-	next = find_prev(tb, stack, lastkey);
+	next = find_prev(tb, stack, lastkey, lk_base);
     }
 
     while ((this = next) != NULL) {
-	next = find_prev(tb, stack, GETKEY(tb, this->dbterm.tpl));
+	next = find_prev(tb, stack, GETKEY(tb, this->dbterm.tpl), this->dbterm.tpl);
 	if (!((*doit)(tb, this, context, 0)))
 	    return;
     }
@@ -2627,7 +2614,7 @@ static void traverse_backwards(DbTableTree *tb,
  */
 static void traverse_forward(DbTableTree *tb,
 			     DbTreeStack* stack,
-			     Eterm lastkey,
+			     Eterm lastkey, Eterm* lk_base,
 			     int (*doit)(DbTableTree *,
 					 TreeDbTerm *,
 					 void *,
@@ -2646,15 +2633,15 @@ static void traverse_forward(DbTableTree *tb,
 	    this = this->left;
 	}
 	this = TOP_NODE(stack);
-	next = find_next(tb, stack, GETKEY(tb, this->dbterm.tpl));
+	next = find_next(tb, stack, GETKEY(tb, this->dbterm.tpl), this->dbterm.tpl);
 	if (!((*doit)(tb, this, context, 1)))
 	    return;
     } else {
-	next = find_next(tb, stack, lastkey);
+	next = find_next(tb, stack, lastkey, lk_base);
     }
 
     while ((this = next) != NULL) {
-	next = find_next(tb, stack, GETKEY(tb, this->dbterm.tpl));
+	next = find_next(tb, stack, GETKEY(tb, this->dbterm.tpl), this->dbterm.tpl);
 	if (!((*doit)(tb, this, context, 1)))
 	    return;
     }
@@ -2680,7 +2667,7 @@ static int key_given(DbTableTree *tb, Eterm pattern, TreeDbTerm **ret,
 	if (( this = find_node(tb, key) ) == NULL) {
 	    return -1;
 	}
-	*ret = this; 
+	*ret = this;
 	return 1;
     } else if (partly_bound != NULL && key != am_Underscore && 
 	       db_is_variable(key) < 0)
@@ -2691,7 +2678,7 @@ static int key_given(DbTableTree *tb, Eterm pattern, TreeDbTerm **ret,
 
 
 
-static Sint do_cmp_partly_bound(Eterm a, Eterm b, int *done)
+static Sint do_cmp_partly_bound(Eterm a, Eterm b, Eterm* b_base, int *done)
 {
     Eterm* aa;
     Eterm* bb;
@@ -2705,44 +2692,44 @@ static Sint do_cmp_partly_bound(Eterm a, Eterm b, int *done)
 	*done = 1;
 	return 0;
     }
-    if (a == b)
+    if (is_same(a,NULL,b,b_base))
 	return 0;
     
     switch (a & _TAG_PRIMARY_MASK) {
     case TAG_PRIMARY_LIST:
 	if (!is_list(b)) {
-	    return cmp(a,b);
+	    return cmp_rel(a,NULL,b,b_base);
 	}
 	aa = list_val(a);
-	bb = list_val(b);
+	bb = list_val_rel(b,b_base);
 	while (1) {
-	    if ((j = do_cmp_partly_bound(*aa++, *bb++, done)) != 0 || *done) 
+	    if ((j = do_cmp_partly_bound(*aa++, *bb++, b_base, done)) != 0 || *done)
 		return j;
 	    if (*aa==*bb)
 		return 0;
 	    if (is_not_list(*aa) || is_not_list(*bb))
-		return do_cmp_partly_bound(*aa, *bb, done);
+		return do_cmp_partly_bound(*aa, *bb, b_base, done);
 	    aa = list_val(*aa);
-	    bb = list_val(*bb);
+	    bb = list_val_rel(*bb,b_base);
 	}
     case TAG_PRIMARY_BOXED:
 	if ((b & _TAG_PRIMARY_MASK) != TAG_PRIMARY_BOXED) {
-	    return cmp(a,b);
+	    return cmp_rel(a,NULL,b,b_base);
 	}
 	a_hdr = ((*boxed_val(a)) & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE;
-	b_hdr = ((*boxed_val(b)) & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE;
+	b_hdr = ((*boxed_val_rel(b,b_base)) & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE;
 	if (a_hdr != b_hdr) {
-	    return cmp(a, b);
+	    return cmp_rel(a, NULL, b, b_base);
 	}
 	if (a_hdr == (_TAG_HEADER_ARITYVAL >> _TAG_PRIMARY_SIZE)) {
 	    aa = tuple_val(a);
-	    bb = tuple_val(b);
+	    bb = tuple_val_rel(b, b_base);
 	    /* compare the arities */
 	    i = arityval(*aa);	/* get the arity*/
 	    if (i < arityval(*bb)) return(-1);
 	    if (i > arityval(*bb)) return(1);
 	    while (i--) {
-		if ((j = do_cmp_partly_bound(*++aa, *++bb, done)) != 0 
+		if ((j = do_cmp_partly_bound(*++aa, *++bb, b_base, done)) != 0
 		    || *done) 
 		    return j;
 	    }
@@ -2750,14 +2737,14 @@ static Sint do_cmp_partly_bound(Eterm a, Eterm b, int *done)
 	}
 	/* Drop through */
       default:
-	  return cmp(a, b);
+	  return cmp_rel(a, NULL, b, b_base);
     }
 }
 
-static Sint cmp_partly_bound(Eterm partly_bound_key, Eterm bound_key) 
+static Sint cmp_partly_bound(Eterm partly_bound_key, Eterm bound_key, Eterm* bk_base)
 {
     int done = 0;
-    Sint ret = do_cmp_partly_bound(partly_bound_key, bound_key, &done);
+    Sint ret = do_cmp_partly_bound(partly_bound_key, bound_key, bk_base, &done);
 #ifdef HARDDEBUG
     erts_fprintf(stderr,"\ncmp_partly_bound: %T", partly_bound_key);
     if (ret < 0)
@@ -2766,7 +2753,7 @@ static Sint cmp_partly_bound(Eterm partly_bound_key, Eterm bound_key)
 	erts_fprintf(stderr," > ");
     else
 	erts_fprintf(stderr," == ");
-    erts_fprintf(stderr,"%T\n",bound_key);
+    erts_fprintf(stderr,"%T\n",bound_key);  // SVERK: printing rterm
 #endif
     return ret;
 }
@@ -2853,7 +2840,7 @@ static int do_partly_bound_can_match_lesser(Eterm a, Eterm b,
 
     if (not_eq_tags(a,b)) {
 	*done = 1;
-	return (cmp(a, b) < 0) ? 1 : 0;
+	return (CMP(a, b) < 0) ? 1 : 0;
     }
 
     /* we now know that tags are the same */
@@ -2889,7 +2876,7 @@ static int do_partly_bound_can_match_lesser(Eterm a, Eterm b,
 	    bb = list_val(*bb);
 	}
     default:
-	if((i = cmp(a, b)) != 0) {
+	if((i = CMP(a, b)) != 0) {
 	    *done = 1;
 	}
 	return (i < 0) ? 1 : 0;
@@ -2924,7 +2911,7 @@ static int do_partly_bound_can_match_greater(Eterm a, Eterm b,
 
     if (not_eq_tags(a,b)) {
 	*done = 1;
-	return (cmp(a, b) > 0) ? 1 : 0;
+	return (CMP(a, b) > 0) ? 1 : 0;
     }
 
     /* we now know that tags are the same */
@@ -2960,7 +2947,7 @@ static int do_partly_bound_can_match_greater(Eterm a, Eterm b,
 	    bb = list_val(*bb);
 	}
     default:
-	if((i = cmp(a, b)) != 0) {
+	if((i = CMP(a, b)) != 0) {
 	    *done = 1;
 	}
 	return (i > 0) ? 1 : 0;
@@ -2983,12 +2970,12 @@ static int doit_select(DbTableTree *tb, TreeDbTerm *this, void *ptr,
     if (sc->end_condition != NIL && 
 	((forward && 
 	  cmp_partly_bound(sc->end_condition, 
-			   GETKEY_WITH_POS(sc->keypos, 
-					   this->dbterm.tpl)) < 0) ||
+			   GETKEY_WITH_POS(sc->keypos, this->dbterm.tpl),
+			   this->dbterm.tpl) < 0) ||
 	 (!forward && 
 	  cmp_partly_bound(sc->end_condition, 
-			   GETKEY_WITH_POS(sc->keypos, 
-					   this->dbterm.tpl)) > 0))) {
+			   GETKEY_WITH_POS(sc->keypos, this->dbterm.tpl),
+			   this->dbterm.tpl) > 0))) {
 	return 0;
     }
     ret = db_prog_match_and_copy(&tb->common,sc->p,sc->mp,sc->all_objects,
@@ -3020,8 +3007,8 @@ static int doit_select_count(DbTableTree *tb, TreeDbTerm *this, void *ptr,
     /* Always backwards traversing */
     if (sc->end_condition != NIL && 
 	(cmp_partly_bound(sc->end_condition, 
-			  GETKEY_WITH_POS(sc->keypos, 
-					  this->dbterm.tpl)) > 0)) {
+			  GETKEY_WITH_POS(sc->keypos, this->dbterm.tpl),
+			  this->dbterm.tpl) > 0)) {
 	return 0;
     }
     ret = db_prog_match_and_copy(&tb->common, sc->p, sc->mp, 0,
@@ -3047,12 +3034,12 @@ static int doit_select_chunk(DbTableTree *tb, TreeDbTerm *this, void *ptr,
     if (sc->end_condition != NIL && 
 	((forward && 
 	  cmp_partly_bound(sc->end_condition, 
-			   GETKEY_WITH_POS(sc->keypos, 
-					   this->dbterm.tpl)) < 0) ||
+			   GETKEY_WITH_POS(sc->keypos, this->dbterm.tpl),
+			   this->dbterm.tpl) < 0) ||
 	 (!forward && 
 	  cmp_partly_bound(sc->end_condition, 
-			   GETKEY_WITH_POS(sc->keypos, 
-					   this->dbterm.tpl)) > 0))) {
+			   GETKEY_WITH_POS(sc->keypos, this->dbterm.tpl),
+			   this->dbterm.tpl) > 0))) {
 	return 0;
     }
 
@@ -3090,14 +3077,14 @@ static int doit_select_delete(DbTableTree *tb, TreeDbTerm *this, void *ptr,
     
     if (sc->end_condition != NIL && 
 	cmp_partly_bound(sc->end_condition, 
-			 GETKEY_WITH_POS(sc->keypos, 
-					 this->dbterm.tpl)) > 0)
+			 GETKEY_WITH_POS(sc->keypos, this->dbterm.tpl),
+			 this->dbterm.tpl) > 0)
 	return 0;
     ret = db_prog_match_and_copy(&tb->common, sc->p, sc->mp, 0,
 				 &this->dbterm, NULL, 0);
     if (ret == am_true) {
 	key = GETKEY(sc->tb, this->dbterm.tpl);
-	linkout_tree(sc->tb, key);
+	linkout_tree(sc->tb, key, this->dbterm.tpl);
 	sc->erase_lastterm = 1;
 	++sc->accum;
     }
diff --git a/erts/emulator/beam/erl_db_util.c b/erts/emulator/beam/erl_db_util.c
index 2852fb93fe..cff208ffa7 100644
--- a/erts/emulator/beam/erl_db_util.c
+++ b/erts/emulator/beam/erl_db_util.c
@@ -422,9 +422,10 @@ get_match_pseudo_process(Process *c_p, Uint heap_size)
     mpsp = match_pseudo_process;
     cleanup_match_pseudo_process(mpsp, 0);
 #endif
-    if (heap_size > ERTS_DEFAULT_MS_HEAP_SIZE)
+    if (heap_size > ERTS_DEFAULT_MS_HEAP_SIZE) {
 	mpsp->heap = (Eterm *) erts_alloc(ERTS_ALC_T_DB_MS_RUN_HEAP,
 					  heap_size*sizeof(Uint));
+    }
     else {
 	ASSERT(mpsp->heap == &mpsp->default_heap[0]);
     }
@@ -467,23 +468,6 @@ erts_match_set_release_result(Process* c_p)
 
 static erts_smp_atomic_t trace_control_word;
 
-
-Eterm
-erts_ets_copy_object(Eterm obj, Process* to)
-{
-    Uint size = size_object(obj);
-    Eterm* hp = HAlloc(to, size);
-    Eterm res;
-
-    res = copy_struct(obj, size, &hp, &MSO(to));
-#ifdef DEBUG
-    if (eq(obj, res) == 0) {
-	erl_exit(1, "copy not equal to source\n");
-    }
-#endif
-    return res;
-}
-
 /* This needs to be here, before the bif table... */
 
 static Eterm db_set_trace_control_word_fake_1(Process *p, Eterm val);
@@ -1609,7 +1593,7 @@ static Eterm dpm_array_to_list(Process *psp, Eterm *arr, int arity)
 /*
 ** Execution of the match program, this is Pam.
 ** May return THE_NON_VALUE, which is a bailout.
-** the para meter 'arity' is only used if 'term' is actually an array,
+** the parameter 'arity' is only used if 'term' is actually an array,
 ** i.e. 'DCOMP_TRACE' was specified 
 */
 Eterm db_prog_match(Process *c_p, Binary *bprog, Eterm term, 
@@ -1639,6 +1623,7 @@ Eterm db_prog_match(Process *c_p, Binary *bprog, Eterm term,
     Eterm (*bif)(Process*, ...);
     int fail_label;
     int atomic_trace;
+    Eterm* base = is_immed(term) ? NULL : termp;
 #ifdef DMC_DEBUG
     Uint *heap_fence;
     Uint *eheap_fence;
@@ -1646,6 +1631,8 @@ Eterm db_prog_match(Process *c_p, Binary *bprog, Eterm term,
     Uint save_op;
 #endif /* DMC_DEBUG */
 
+    ASSERT(base==NULL);  // SVERK: base not used for now, maybe remove
+
     mpsp = get_match_pseudo_process(c_p, prog->heap_size);
     psp = &mpsp->process;
 
@@ -1740,9 +1727,9 @@ restart:
 	    hp[n] = dpm_array_to_list(psp, termp, arity);
 	    break;
 	case matchTuple: /* *ep is a tuple of arity n */
-	    if (!is_tuple(*ep))
+	    if (!is_tuple_rel(*ep,base))
 		FAIL();
-	    ep = tuple_val(*ep);
+	    ep = tuple_val_rel(*ep,base);
 	    n = *pc++;
 	    if (arityval(*ep) != n)
 		FAIL();
@@ -1750,9 +1737,9 @@ restart:
 	    break;
 	case matchPushT: /* *ep is a tuple of arity n, 
 			    push ptr to first element */
-	    if (!is_tuple(*ep))
+	    if (!is_tuple_rel(*ep,base))
 		FAIL();
-	    tp = tuple_val(*ep);
+	    tp = tuple_val_rel(*ep,base);
 	    n = *pc++;
 	    if (arityval(*tp) != n)
 		FAIL();
@@ -1762,12 +1749,12 @@ restart:
 	case matchList:
 	    if (!is_list(*ep))
 		FAIL();
-	    ep = list_val(*ep);
+	    ep = list_val_rel(*ep,base);
 	    break;
 	case matchPushL:
 	    if (!is_list(*ep))
 		FAIL();
-	    *sp++ = list_val(*ep);
+	    *sp++ = list_val_rel(*ep,base);
 	    ++ep;
 	    break;
 	case matchPop:
@@ -1779,37 +1766,37 @@ restart:
 	    break;
 	case matchCmp:
 	    n = *pc++;
-	    if (!eq(hp[n],*ep))
+	    if (!eq_rel(hp[n],*ep,base))
 		FAIL();
 	    ++ep;
 	    break;
 	case matchEqBin:
 	    t = (Eterm) *pc++;
-	    if (!eq(*ep,t))
+	    if (!eq_rel(t,*ep,base))
 		FAIL();
 	    ++ep;
 	    break;
 	case matchEqFloat:
-	    if (!is_float(*ep))
+	    if (!is_float_rel(*ep,base))
 		FAIL();
-	    if (memcmp(float_val(*ep) + 1, pc, sizeof(double)))
+	    if (memcmp(float_val_rel(*ep,base) + 1, pc, sizeof(double)))
 		FAIL();
 	    pc += TermWords(2);
 	    ++ep;
 	    break;
 	case matchEqRef:
-	    if (!is_ref(*ep))
+	    if (!is_ref_rel(*ep,base))
 		FAIL();
-	    if (!eq(*ep, make_internal_ref((Uint *) pc)))
+	    if (!eq_rel(make_internal_ref((Uint *) pc), *ep, base))
 		FAIL();
 	    i = thing_arityval(*((Uint *) pc));
 	    pc += TermWords(i+1);
 	    ++ep;
 	    break;
 	case matchEqBig:
-	    if (!is_big(*ep))
+	    if (!is_big_rel(*ep,base))
 		FAIL();
-	    tp = big_val(*ep);
+	    tp = big_val_rel(*ep,base);
 	    {
 		Eterm *epc = (Eterm *) pc;
 		if (*tp != *epc)
@@ -1825,7 +1812,8 @@ restart:
 	    ++ep;
 	    break;
 	case matchEq:
-	    t = (Eterm) *pc++; 
+	    t = (Eterm) *pc++;
+	    ASSERT(is_immed(t));
 	    if (t != *ep++)
 		FAIL();
 	    break;
@@ -1909,7 +1897,8 @@ restart:
 	    *esp++ = hp[*pc++];
 	    break;
 	case matchPushExpr:
-	    *esp++ = term;
+	    ASSERT(is_tuple_rel(term,base));
+	    *esp++ = make_tuple(tuple_val_rel(term,base));
 	    break;
 	case matchPushArrayAsList:
 	    n = arity; /* Only happens when 'term' is an array */
@@ -2327,13 +2316,13 @@ void db_free_dmc_err_info(DMCErrInfo *ei){
 ** Store bignum in *hpp and increase *hpp accordingly.
 ** *hpp is assumed to be large enough to hold the result.
 */
-Eterm db_add_counter(Eterm** hpp, Eterm counter, Eterm incr)
+Eterm db_add_counter(Eterm** hpp, Wterm counter, Eterm incr)
 {
     DeclareTmpHeapNoproc(big_tmp,2);
     Eterm res;
     Sint ires;
-    Eterm arg1;
-    Eterm arg2;
+    Wterm arg1;
+    Wterm arg2;
 
     if (is_both_small(counter,incr)) {
 	ires = signed_val(counter) + signed_val(incr);
@@ -2374,6 +2363,44 @@ Eterm db_add_counter(Eterm** hpp, Eterm counter, Eterm incr)
     }
 }
 
+/* Must be called to read elements after db_lookup_dbterm.
+** Will decompress if needed.
+** HEALFWORD_HEAP: Will convert from relative to Wterm format if needed.
+*/
+Wterm db_do_read_element(DbUpdateHandle* handle, Sint position)
+{
+#if HALFWORD_HEAP
+    Eterm elem = handle->new_tuple[position];
+    Eterm* base = handle->dbterm->tpl;
+
+    if (elem == THE_NON_VALUE) {
+	elem = handle->dbterm->tpl[position];
+	ASSERT(is_value(elem));
+    }
+    else if (handle->new_tuple != handle->dbterm->tpl
+	     || handle->tb->common.compress) {
+	base = NULL;
+    }
+    if (!is_header(elem)) {
+	return is_immed(elem) ? elem : rterm2wterm(elem, base);
+    }
+#else
+    Eterm elem = handle->dbterm->tpl[position];
+    if (!is_header(elem)) {
+	return elem;
+    }
+#endif
+
+    ASSERT(((DbTableCommon*)handle->tb)->compress);
+    ASSERT(!handle->mustResize);
+    handle->dbterm = db_alloc_tmp_uncompressed((DbTableCommon*)handle->tb, handle->dbterm);
+    handle->mustResize = 1;
+#if HALFWORD_HEAP
+    handle->new_tuple = handle->dbterm->tpl;
+#endif
+    return handle->dbterm->tpl[position];
+}
+
 /*
 ** Update one element:
 ** handle:   Initialized by db_lookup_dbterm()
@@ -2385,6 +2412,61 @@ void db_do_update_element(DbUpdateHandle* handle,
 			  Sint position,
 			  Eterm newval)
 {
+#if HALFWORD_HEAP
+    Eterm oldval = handle->new_tuple[position];
+    Eterm* old_base;
+    Uint newval_sz;
+    Uint oldval_sz;
+
+    if (is_both_immed(newval,oldval)) {
+	handle->new_tuple[position] = newval;
+#ifdef DEBUG_CLONE
+	if (handle->dbterm->debug_clone) {
+	    handle->dbterm->debug_clone[position] = newval;
+	}
+#endif
+	return;
+    }
+
+    if (handle->tb->common.compress) {
+	if (!handle->mustResize) {
+	    handle->dbterm = db_alloc_tmp_uncompressed(&handle->tb->common,
+						       handle->dbterm);
+	    handle->mustResize = 1;
+	    handle->new_tuple = handle->dbterm->tpl;
+	    oldval = handle->dbterm->tpl[position];
+	}
+	old_base = NULL;
+    }
+    else {
+	if (handle->new_tuple == handle->dbterm->tpl) {
+	    int i = header_arity(handle->new_tuple[0]);
+	    handle->new_tuple = erts_alloc(ERTS_ALC_T_TMP, (i+1)*sizeof(Eterm));
+	    handle->new_tuple[0] =  handle->dbterm->tpl[0];
+	    for ( ; i ; i--) {
+		handle->new_tuple[i] = THE_NON_VALUE;
+	    }
+	}
+	if (handle->new_tuple[position] == THE_NON_VALUE) {
+	    oldval = handle->dbterm->tpl[position];
+	    old_base = handle->dbterm->tpl;
+	}
+	else {
+	    old_base = NULL;
+	}
+    }
+    oldval_sz = is_immed(oldval) ? 0 : size_object_rel(oldval,old_base);
+    newval_sz = is_immed(newval) ? 0 : size_object(newval);
+
+    handle->new_size = handle->new_size - oldval_sz + newval_sz;
+
+    /* write new value in old dbterm, finalize will make a flat copy */
+    handle->new_tuple[position] = newval;
+    handle->mustResize = 1;
+
+
+#else /****** !HALFWORD_HEAP ******/
+
     Eterm oldval = handle->dbterm->tpl[position];
     Eterm* newp;
     Eterm* oldp;
@@ -2425,7 +2507,7 @@ void db_do_update_element(DbUpdateHandle* handle,
 			oldval_sz = header_arity(*oldp) + 1;
 			if (oldval_sz == newval_sz) {
 			    /* "self contained" terms of same size, do memcpy */
-				sys_memcpy(oldp, newp, newval_sz*sizeof(Eterm));
+			    sys_memcpy(oldp, newp, newval_sz*sizeof(Eterm));
 			    return;
 			}
 			goto both_size_set;
@@ -2440,7 +2522,7 @@ void db_do_update_element(DbUpdateHandle* handle,
 
     newval_sz = is_immed(newval) ? 0 : size_object(newval);
 new_size_set:
-	
+
     oldval_sz = is_immed(oldval) ? 0 : size_object(oldval);
 both_size_set:
 
@@ -2449,6 +2531,7 @@ both_size_set:
     /* write new value in old dbterm, finalize will make a flat copy */	
     handle->dbterm->tpl[position] = newval;
     handle->mustResize = 1;
+#endif /* !HALFWORD_HEAP */
 }
 
 static ERTS_INLINE byte* db_realloc_term(DbTableCommon* tb, void* old,
@@ -2547,7 +2630,7 @@ static void* copy_to_comp(DbTableCommon* tb, Eterm obj, DbTerm* dest,
     tpl[arity + 1] = alloc_size;
 
     tmp_offheap.first = NULL;
-    tpl[tb->keypos] = copy_struct(key, size_object(key), &top.ep, &tmp_offheap);
+    tpl[tb->keypos] = copy_struct_rel(key, size_object(key), &top.ep, &tmp_offheap, NULL, tpl);
     dest->first_oh = tmp_offheap.first;
     for (i=1; i<=arity; i++) {
 	if (i != tb->keypos) {
@@ -2566,7 +2649,7 @@ static void* copy_to_comp(DbTableCommon* tb, Eterm obj, DbTerm* dest,
 	Eterm* dbg_top = erts_alloc(ERTS_ALC_T_DB_TERM, dest->size * sizeof(Eterm));
 	dest->debug_clone = dbg_top;
 	tmp_offheap.first = dest->first_oh;
-	copy_struct(obj, dest->size, &dbg_top, &tmp_offheap);
+	copy_struct_rel(obj, dest->size, &dbg_top, &tmp_offheap, NULL, dbg_top);
 	dest->first_oh = tmp_offheap.first;
 	ASSERT(dbg_top == dest->debug_clone + dest->size);
     }
@@ -2613,7 +2696,7 @@ void* db_store_term(DbTableCommon *tb, DbTerm* old, Uint offset, Eterm obj)
     newp->size = size;
     top = newp->tpl;
     tmp_offheap.first  = NULL;
-    copy_struct(obj, size, &top, &tmp_offheap);
+    copy_struct_rel(obj, size, &top, &tmp_offheap, NULL, top);
     newp->first_oh = tmp_offheap.first;
 #ifdef DEBUG_CLONE
     newp->debug_clone = NULL;
@@ -2652,7 +2735,7 @@ void* db_store_term_comp(DbTableCommon *tb, DbTerm* old, Uint offset, Eterm obj)
     top = copy_to_comp(tb, obj, newp, new_sz);
     ASSERT(top <= basep + new_sz);
 
-    // SVERK: realloc?
+    /* ToDo: Maybe realloc if ((basep+new_sz) - top) > WASTED_SPACE_LIMIT */
 
     return basep;
 }
@@ -2660,6 +2743,66 @@ void* db_store_term_comp(DbTableCommon *tb, DbTerm* old, Uint offset, Eterm obj)
 
 void db_finalize_resize(DbUpdateHandle* handle, Uint offset)
 {
+#if HALFWORD_HEAP
+    DbTable* tbl = handle->tb;
+    DbTerm* newDbTerm;
+    Uint alloc_sz = offset +
+	(tbl->common.compress ?
+	 db_size_dbterm_comp(&tbl->common, make_tuple(handle->dbterm->tpl)) :
+	 sizeof(DbTerm)+sizeof(Eterm)*(handle->new_size-1));
+    byte* newp = erts_db_alloc(ERTS_ALC_T_DB_TERM, tbl, alloc_sz);
+    byte* oldp = *(handle->bp);
+
+    sys_memcpy(newp, oldp, offset);  /* copy only hash/tree header */
+    *(handle->bp) = newp;
+    newDbTerm = (DbTerm*) (newp + offset);
+    newDbTerm->size = handle->new_size;
+
+    /* make a flat copy */
+
+    if (tbl->common.compress) {
+	copy_to_comp(&tbl->common, make_tuple(handle->dbterm->tpl),
+		     newDbTerm, alloc_sz);
+	db_free_tmp_uncompressed(handle->dbterm);
+    }
+    else {
+	ErlOffHeap tmp_offheap;
+	int i, arity = header_arity(handle->dbterm->tpl[0]);
+	Eterm* top = newDbTerm->tpl + arity + 1;
+
+	ASSERT(handle->new_tuple != handle->dbterm->tpl);
+	tmp_offheap.first = NULL;
+
+	newDbTerm->tpl[0] = handle->dbterm->tpl[0];
+	for (i=1; i<=arity; i++) {
+	    Eterm* tpl;
+	    Eterm* src_base;
+
+
+	    if (handle->new_tuple[i] == THE_NON_VALUE) {
+		tpl = handle->dbterm->tpl;
+		src_base = tpl;
+	    }
+	    else {
+		tpl = handle->new_tuple;
+		src_base = NULL;
+	    }
+	    newDbTerm->tpl[i] = copy_struct_rel(tpl[i],
+						size_object_rel(tpl[i],src_base),
+						&top, &tmp_offheap, src_base,
+						newDbTerm->tpl);
+	}
+
+	newDbTerm->first_oh = tmp_offheap.first;
+#ifdef DEBUG_CLONE
+	newDbTerm->debug_clone = NULL;
+#endif
+	ASSERT((byte*)top <= (newp + alloc_sz));
+	ASSERT(handle->new_tuple != handle->dbterm->tpl);
+	erts_free(ERTS_ALC_T_TMP, handle->new_tuple);
+    }
+
+#else /***** !HALFWORD_HEAP *****/
     DbTable* tbl = handle->tb;
     DbTerm* newDbTerm;
     Uint alloc_sz = offset +
@@ -2694,6 +2837,7 @@ void db_finalize_resize(DbUpdateHandle* handle, Uint offset)
 #endif
 	ASSERT((byte*)top <= (newp + alloc_sz));
     }
+#endif
 }
 
 Eterm db_copy_from_comp(DbTableCommon* tb, DbTerm* bp, Eterm** hpp,
@@ -2705,9 +2849,9 @@ Eterm db_copy_from_comp(DbTableCommon* tb, DbTerm* bp, Eterm** hpp,
     hp[0] = bp->tpl[0];
     *hpp += arity + 1;
 
-    hp[tb->keypos] = copy_struct(bp->tpl[tb->keypos],
-				 size_object(bp->tpl[tb->keypos]),
-				 hpp, off_heap);
+    hp[tb->keypos] = copy_struct_rel(bp->tpl[tb->keypos],
+				     size_object_rel(bp->tpl[tb->keypos], bp->tpl),
+				     hpp, off_heap, bp->tpl, NULL);
     for (i=arity; i>0; i--) {
 	if (i != tb->keypos) {
 	    if (is_immed(bp->tpl[i])) {
@@ -2721,7 +2865,7 @@ Eterm db_copy_from_comp(DbTableCommon* tb, DbTerm* bp, Eterm** hpp,
     }
     ASSERT((*hpp - hp) <= bp->size);
 #ifdef DEBUG_CLONE
-    ASSERT(eq(make_tuple(hp),make_tuple(bp->debug_clone)));
+    ASSERT(eq_rel(make_tuple(hp),make_tuple(bp->debug_clone),bp->debug_clone));
 #endif
     return make_tuple(hp);
 }
@@ -2744,14 +2888,14 @@ Eterm db_copy_element_from_ets(DbTableCommon* tb, Process* p,
 	hp += extra;
 	HRelease(p, endp, hp);
 #ifdef DEBUG_CLONE
-	ASSERT(eq(copy,obj->debug_clone[pos]));
+	ASSERT(eq_rel(copy, obj->debug_clone[pos], obj->debug_clone));
 #endif
 	return copy;
     }
     else {
-	Uint sz = size_object(obj->tpl[pos]);
+	Uint sz = size_object_rel(obj->tpl[pos], obj->tpl);
 	*hpp = HAlloc(p, sz + extra);
-	return copy_struct(obj->tpl[pos], sz, hpp, &MSO(p));
+	return copy_struct_rel(obj->tpl[pos], sz, hpp, &MSO(p), obj->tpl, NULL);
     }
 }
 
@@ -2765,7 +2909,7 @@ void db_cleanup_offheap_comp(DbTerm* obj)
     ProcBin tmp;
 
     for (u.hdr = obj->first_oh; u.hdr; u.hdr = u.hdr->next) {
-	if ((UWord)u.voidp % sizeof(UWord) != 0) { /* unaligned ptr */
+	if ((UWord)u.voidp % sizeof(Uint) != 0) { /* unaligned ptr */
 	    sys_memcpy(&tmp, u.voidp, sizeof(tmp));
 	    /* Warning, must pass (void*)-variable to memcpy. Otherwise it will
 	       cause Bus error on Sparc due to false compile time assumptions
@@ -4744,6 +4888,23 @@ Eterm db_prog_match_and_copy(DbTableCommon* tb, Process* c_p, Binary* bprog,
     if (tb->compress) {
 	obj = db_alloc_tmp_uncompressed(tb, obj);
     }
+#if HALFWORD_HEAP
+    else { // SVERK: Heavy solution; make tmp copy
+	ErlOffHeap tmp_offheap;
+	Eterm* hp;
+	DbTerm* tmp = erts_alloc(ERTS_ALC_T_TMP,
+				     sizeof(DbTerm) + obj->size*sizeof(Eterm));
+	hp = tmp->tpl;
+	tmp_offheap.first = NULL;
+	copy_shallow_rel(obj->tpl, obj->size, &hp, &tmp_offheap, obj->tpl);
+	tmp->size = obj->size;
+	tmp->first_oh = tmp_offheap.first;
+	#ifdef DEBUG_CLONE
+	tmp->debug_clone = NULL;
+	#endif
+	obj = tmp;
+    }
+#endif
 
     res = db_prog_match(c_p, bprog, make_tuple(obj->tpl), NULL, 0, &dummy);
 
@@ -4762,6 +4923,9 @@ Eterm db_prog_match_and_copy(DbTableCommon* tb, Process* c_p, Binary* bprog,
     if (tb->compress) {
 	db_free_tmp_uncompressed(obj);
     }
+#if HALFWORD_HEAP
+    else db_free_tmp_uncompressed(obj); // SVERK misleading name
+#endif
     return res;
 }
 
diff --git a/erts/emulator/beam/erl_db_util.h b/erts/emulator/beam/erl_db_util.h
index 58ad39d772..600110e745 100644
--- a/erts/emulator/beam/erl_db_util.h
+++ b/erts/emulator/beam/erl_db_util.h
@@ -86,6 +86,9 @@ typedef struct {
     Uint new_size;
     int mustResize;
     void* lck;
+#if HALFWORD_HEAP
+    Eterm* new_tuple;
+#endif
 } DbUpdateHandle;
 
 
@@ -255,7 +258,14 @@ typedef struct db_table_common {
 #define NFIXED(T) (erts_refc_read(&(T)->common.ref,0))
 #define IS_FIXED(T) (NFIXED(T) != 0) 
 
-Eterm erts_ets_copy_object(Eterm, Process*);
+/*
+ * tplp is an untagged pointer to a tuple we know is large enough
+ * and dth is a pointer to a DbTableHash.
+ */
+#define GETKEY(dth, tplp)   (*((tplp) + ((DbTableCommon*)(dth))->keypos))
+
+
+ERTS_GLB_INLINE Eterm db_copy_key(Process* p, DbTable* tb, DbTerm* obj);
 Eterm db_copy_from_comp(DbTableCommon* tb, DbTerm* bp, Eterm** hpp,
 			ErlOffHeap* off_heap);
 int db_eq_comp(DbTableCommon* tb, Eterm a, DbTerm* b);
@@ -264,9 +274,23 @@ DbTerm* db_alloc_tmp_uncompressed(DbTableCommon* tb, DbTerm* org);
 ERTS_GLB_INLINE Eterm db_copy_object_from_ets(DbTableCommon* tb, DbTerm* bp,
 					      Eterm** hpp, ErlOffHeap* off_heap);
 ERTS_GLB_INLINE int db_eq(DbTableCommon* tb, Eterm a, DbTerm* b);
-ERTS_GLB_INLINE Eterm db_do_read_element(DbUpdateHandle* handle, Sint position);
+Wterm db_do_read_element(DbUpdateHandle* handle, Sint position);
 
 #if ERTS_GLB_INLINE_INCL_FUNC_DEF
+
+ERTS_GLB_INLINE Eterm db_copy_key(Process* p, DbTable* tb, DbTerm* obj)
+{
+    Eterm key = GETKEY(tb, obj->tpl);
+    if IS_CONST(key) return key;
+    else {
+	Uint size = size_object_rel(key, obj->tpl);
+	Eterm* hp = HAlloc(p, size);
+	Eterm res = copy_struct_rel(key, size, &hp, &MSO(p), obj->tpl, NULL);
+	ASSERT(eq_rel(res,key,obj->tpl));
+	return res;
+    }
+}
+
 ERTS_GLB_INLINE Eterm db_copy_object_from_ets(DbTableCommon* tb, DbTerm* bp,
 					      Eterm** hpp, ErlOffHeap* off_heap)
 {
@@ -274,49 +298,27 @@ ERTS_GLB_INLINE Eterm db_copy_object_from_ets(DbTableCommon* tb, DbTerm* bp,
 	return db_copy_from_comp(tb, bp, hpp, off_heap);
     }
     else {
-	return copy_shallow(bp->tpl, bp->size, hpp, off_heap);
+	return copy_shallow_rel(bp->tpl, bp->size, hpp, off_heap, bp->tpl);
     }
 }
 
 ERTS_GLB_INLINE int db_eq(DbTableCommon* tb, Eterm a, DbTerm* b)
 {
     if (!tb->compress) {
-	return eq(a, make_tuple(b->tpl));
+	return eq_rel(a, make_tuple_rel(b->tpl,b->tpl), b->tpl);
     }
     else {
 	return db_eq_comp(tb, a, b);
     }
 }
 
-/* Must be called to read elements after db_lookup_dbterm.
-** Will decompress if needed. */
-ERTS_GLB_INLINE Eterm db_do_read_element(DbUpdateHandle* handle, Sint position)
-{
-    Eterm elem = handle->dbterm->tpl[position];
-    if (!is_header(elem)) {
-	return elem;
-    }
-    ASSERT(((DbTableCommon*)handle->tb)->compress);
-    ASSERT(!handle->mustResize);
-    handle->dbterm = db_alloc_tmp_uncompressed((DbTableCommon*)handle->tb, handle->dbterm);
-    handle->mustResize = 1;
-    return handle->dbterm->tpl[position];
-}
-
 #endif /* ERTS_GLB_INLINE_INCL_FUNC_DEF */
 
-/* optimised version of copy_object (normal case? atomic object) */
-#define COPY_OBJECT(obj, p, objp) \
-   if (IS_CONST(obj)) { *(objp) = (obj); } \
-   else { *objp = erts_ets_copy_object(obj, p); }
 
 #define DB_READ  (DB_PROTECTED|DB_PUBLIC)
 #define DB_WRITE DB_PUBLIC
 #define DB_INFO  (DB_PROTECTED|DB_PUBLIC|DB_PRIVATE)
 
-/* tb is an DbTableCommon and obj is an Eterm (tagged) */
-#define TERM_GETKEY(tb, obj) db_getkey((tb)->common.keypos, (obj)) 
-
 #define ONLY_WRITER(P,T) (((T)->common.status & (DB_PRIVATE|DB_PROTECTED)) \
 			  && (T)->common.owner == (P)->id)
 
@@ -337,12 +339,11 @@ Eterm db_copy_element_from_ets(DbTableCommon* tb, Process* p, DbTerm* obj,
 			       Uint pos, Eterm** hpp, Uint extra);
 int db_has_variable(Eterm obj);
 int db_is_variable(Eterm obj);
-Eterm db_do_read_element(DbUpdateHandle* handle, Sint position);
 void db_do_update_element(DbUpdateHandle* handle,
 			  Sint position,
 			  Eterm newval);
 void db_finalize_resize(DbUpdateHandle* handle, Uint offset);
-Eterm db_add_counter(Eterm** hpp, Eterm counter, Eterm incr);
+Eterm db_add_counter(Eterm** hpp, Wterm counter, Eterm incr);
 Eterm db_match_set_lint(Process *p, Eterm matchexpr, Uint flags);
 Binary *db_match_set_compile(Process *p, Eterm matchexpr, 
 			     Uint flags);
diff --git a/erts/emulator/beam/erl_monitors.c b/erts/emulator/beam/erl_monitors.c
index d873c7a701..9dff157411 100644
--- a/erts/emulator/beam/erl_monitors.c
+++ b/erts/emulator/beam/erl_monitors.c
@@ -1,7 +1,7 @@
 /*
  * %CopyrightBegin%
  * 
- * Copyright Ericsson AB 2004-2009. All Rights Reserved.
+ * Copyright Ericsson AB 2004-2010. All Rights Reserved.
  * 
  * The contents of this file are subject to the Erlang Public License,
  * Version 1.1, (the "License"); you may not use this file except in
@@ -85,7 +85,7 @@ static ERTS_INLINE int cmp_mon_ref(Eterm ref1, Eterm ref2)
     if (is_ref_thing_header(*b2)) {
 	return 1;
     }
-    return cmp(ref1,ref2);
+    return CMP(ref1,ref2);
 }
 	    
 #define CP_LINK_VAL(To, Hp, From)				\
@@ -380,7 +380,7 @@ int erts_add_link(ErtsLink **root, Uint type, Eterm pid)
 	    state = 1;
 	    *this = create_link(type,pid);
 	    break;
-	} else if ((c = cmp(pid,(*this)->pid)) < 0) { 
+	} else if ((c = CMP(pid,(*this)->pid)) < 0) {
 	    /* go left */
 	    dstack[dpos++] = DIR_LEFT;
 	    tstack[tpos++] = this;
@@ -415,7 +415,7 @@ erts_add_or_lookup_suspend_monitor(ErtsSuspendMonitor **root, Eterm pid)
 	    state = 1;
 	    res = *this = create_suspend_monitor(pid);
 	    break;
-	} else if ((c = cmp(pid,(*this)->pid)) < 0) { 
+	} else if ((c = CMP(pid,(*this)->pid)) < 0) {
 	    /* go left */
 	    dstack[dpos++] = DIR_LEFT;
 	    tstack[tpos++] = this;
@@ -453,7 +453,7 @@ ErtsLink *erts_add_or_lookup_link(ErtsLink **root, Uint type, Eterm pid)
 	    *this = create_link(type,pid);
 	    ret = *this;
 	    break;
-	} else if ((c = cmp(pid,(*this)->pid)) < 0) { 
+	} else if ((c = CMP(pid,(*this)->pid)) < 0) {
 	    /* go left */
 	    dstack[dpos++] = DIR_LEFT;
 	    tstack[tpos++] = this;
@@ -663,7 +663,7 @@ ErtsLink *erts_remove_link(ErtsLink **root, Eterm pid)
     for (;;) {
 	if (!*this) { /* Failure */
 	    return NULL;
-	} else if ((c = cmp(pid,(*this)->pid)) < 0) { 
+	} else if ((c = CMP(pid,(*this)->pid)) < 0) {
 	    dstack[dpos++] = DIR_LEFT;
 	    tstack[tpos++] = this;
 	    this = &((*this)->left);
@@ -715,7 +715,7 @@ erts_delete_suspend_monitor(ErtsSuspendMonitor **root, Eterm pid)
     for (;;) {
 	if (!*this) { /* Nothing found */
 	    return;
-	} else if ((c = cmp(pid,(*this)->pid)) < 0) { 
+	} else if ((c = CMP(pid,(*this)->pid)) < 0) {
 	    dstack[dpos++] = DIR_LEFT;
 	    tstack[tpos++] = this;
 	    this = &((*this)->left);
@@ -771,7 +771,7 @@ ErtsLink *erts_lookup_link(ErtsLink *root, Eterm pid)
     Sint c;
 
     for (;;) {
-	if (root == NULL || (c = cmp(pid,root->pid)) == 0) {
+	if (root == NULL || (c = CMP(pid,root->pid)) == 0) {
 	    return root;
 	} else if (c < 0) { 
 	    root = root->left;
@@ -787,7 +787,7 @@ erts_lookup_suspend_monitor(ErtsSuspendMonitor *root, Eterm pid)
     Sint c;
 
     for (;;) {
-	if (root == NULL || (c = cmp(pid,root->pid)) == 0) {
+	if (root == NULL || (c = CMP(pid,root->pid)) == 0) {
 	    return root;
 	} else if (c < 0) { 
 	    root = root->left;
diff --git a/erts/emulator/beam/erl_nif.c b/erts/emulator/beam/erl_nif.c
index a680097c2d..b3f0b17ce4 100644
--- a/erts/emulator/beam/erl_nif.c
+++ b/erts/emulator/beam/erl_nif.c
@@ -574,7 +574,7 @@ int enif_is_identical(Eterm lhs, Eterm rhs)
 
 int enif_compare(Eterm lhs, Eterm rhs)
 {
-    return cmp(lhs,rhs);
+    return CMP(lhs,rhs);
 }
 
 int enif_get_tuple(ErlNifEnv* env, Eterm tpl, int* arity, const Eterm** array)
diff --git a/erts/emulator/beam/erl_node_container_utils.h b/erts/emulator/beam/erl_node_container_utils.h
index ae1316eba2..e06a54477c 100644
--- a/erts/emulator/beam/erl_node_container_utils.h
+++ b/erts/emulator/beam/erl_node_container_utils.h
@@ -255,19 +255,32 @@ extern int erts_use_r9_pids_ports;
 
 #define internal_ref_no_of_numbers(x)					\
   (internal_ref_data((x))[0])
+#define internal_thing_ref_no_of_numbers(thing)			        \
+  (internal_thing_ref_data(thing)[0])
 #define internal_ref_numbers(x)						\
   (&internal_ref_data((x))[1])
+#define internal_thing_ref_numbers(thing)				\
+  (&internal_thing_ref_data(thing)[1])
 #define external_ref_no_of_numbers(x)					\
   (external_ref_data((x))[0])
+#define external_thing_ref_no_of_numbers(thing)			        \
+  (external_thing_ref_data(thing)[0])
 #define external_ref_numbers(x)						\
   (&external_ref_data((x))[1])
+#define external_thing_ref_numbers(thing)				\
+  (&external_thing_ref_data(thing)[1])
+
 
 #else
 
 #define internal_ref_no_of_numbers(x)	(internal_ref_data_words((x)))
+#define internal_thing_ref_no_of_numbers(t) (internal_thing_ref_data_words(t))
 #define internal_ref_numbers(x)		(internal_ref_data((x)))
+#define internal_thing_ref_numbers(t)   (internal_thing_ref_data(t))
 #define external_ref_no_of_numbers(x)	(external_ref_data_words((x)))
+#define external_thing_ref_no_of_numbers(t) (external_thing_ref_data_words((t)))
 #define external_ref_numbers(x)		(external_ref_data((x)))
+#define external_thing_ref_numbers(t)   (external_thing_ref_data((t)))
 
 #endif
 
@@ -311,6 +324,8 @@ extern int erts_use_r9_pids_ports;
 					 : external_ref_channel_no((x)))
 #define is_ref(x)			(is_internal_ref((x))		\
 					 || is_external_ref((x)))
+#define is_ref_rel(x,Base)		(is_internal_ref_rel((x),Base)	\
+					 || is_external_ref_rel((x),Base))
 #define is_not_ref(x)			(!is_ref(x))
 
 #endif
diff --git a/erts/emulator/beam/erl_term.c b/erts/emulator/beam/erl_term.c
index c6458a0e45..e4ed685169 100644
--- a/erts/emulator/beam/erl_term.c
+++ b/erts/emulator/beam/erl_term.c
@@ -58,9 +58,9 @@ do { \
 #endif
 
 #if ET_DEBUG
-unsigned tag_val_def_debug(Eterm x, const char *file, unsigned line)
+unsigned tag_val_def_debug(Wterm x, const char *file, unsigned line)
 #else
-unsigned tag_val_def(Eterm x)
+unsigned tag_val_def(Wterm x)
 #define file __FILE__
 #define line __LINE__
 #endif
@@ -125,10 +125,10 @@ FUNTY checked_##FUN(ARGTY x, const char *file, unsigned line) \
 
 ET_DEFINE_CHECKED(Eterm,make_boxed,Eterm*,_is_taggable_pointer);
 ET_DEFINE_CHECKED(int,is_boxed,Eterm,!is_header);
-ET_DEFINE_CHECKED(Eterm*,boxed_val,Eterm,_boxed_precond);
+ET_DEFINE_CHECKED(Eterm*,boxed_val,Wterm,_boxed_precond);
 ET_DEFINE_CHECKED(Eterm,make_list,Eterm*,_is_taggable_pointer);
 ET_DEFINE_CHECKED(int,is_not_list,Eterm,!is_header);
-ET_DEFINE_CHECKED(Eterm*,list_val,Eterm,_list_precond);
+ET_DEFINE_CHECKED(Eterm*,list_val,Wterm,_list_precond);
 ET_DEFINE_CHECKED(Uint,unsigned_val,Eterm,is_small);
 ET_DEFINE_CHECKED(Sint,signed_val,Eterm,is_small);
 ET_DEFINE_CHECKED(Uint,atom_val,Eterm,is_atom);
@@ -136,34 +136,35 @@ ET_DEFINE_CHECKED(Uint,header_arity,Eterm,is_header);
 ET_DEFINE_CHECKED(Uint,arityval,Eterm,is_arity_value);
 ET_DEFINE_CHECKED(Uint,thing_arityval,Eterm,is_thing);
 ET_DEFINE_CHECKED(Uint,thing_subtag,Eterm,is_thing);
-ET_DEFINE_CHECKED(Eterm*,binary_val,Eterm,is_binary);
-ET_DEFINE_CHECKED(Eterm*,fun_val,Eterm,is_fun);
+ET_DEFINE_CHECKED(Eterm*,binary_val,Wterm,is_binary);
+ET_DEFINE_CHECKED(Eterm*,fun_val,Wterm,is_fun);
 ET_DEFINE_CHECKED(int,bignum_header_is_neg,Eterm,_is_bignum_header);
 ET_DEFINE_CHECKED(Eterm,bignum_header_neg,Eterm,_is_bignum_header);
 ET_DEFINE_CHECKED(Uint,bignum_header_arity,Eterm,_is_bignum_header);
-ET_DEFINE_CHECKED(Eterm*,big_val,Eterm,is_big);
-ET_DEFINE_CHECKED(Eterm*,float_val,Eterm,is_float);
-ET_DEFINE_CHECKED(Eterm*,tuple_val,Eterm,is_tuple);
+ET_DEFINE_CHECKED(Eterm*,big_val,Wterm,is_big);
+ET_DEFINE_CHECKED(Eterm*,float_val,Wterm,is_float);
+ET_DEFINE_CHECKED(Eterm*,tuple_val,Wterm,is_tuple);
 ET_DEFINE_CHECKED(Uint,internal_pid_data,Eterm,is_internal_pid);
 ET_DEFINE_CHECKED(struct erl_node_*,internal_pid_node,Eterm,is_internal_pid);
 ET_DEFINE_CHECKED(Uint,internal_port_data,Eterm,is_internal_port);
 ET_DEFINE_CHECKED(struct erl_node_*,internal_port_node,Eterm,is_internal_port);
-ET_DEFINE_CHECKED(Eterm*,internal_ref_val,Eterm,is_internal_ref);
-ET_DEFINE_CHECKED(Uint,internal_ref_data_words,Eterm,is_internal_ref);
-ET_DEFINE_CHECKED(Uint32*,internal_ref_data,Eterm,is_internal_ref);
+ET_DEFINE_CHECKED(Eterm*,internal_ref_val,Wterm,is_internal_ref);
+ET_DEFINE_CHECKED(Uint,internal_ref_data_words,Wterm,is_internal_ref);
+ET_DEFINE_CHECKED(Uint32*,internal_ref_data,Wterm,is_internal_ref);
 ET_DEFINE_CHECKED(struct erl_node_*,internal_ref_node,Eterm,is_internal_ref);
-ET_DEFINE_CHECKED(Eterm*,external_val,Eterm,is_external);
-ET_DEFINE_CHECKED(Uint,external_data_words,Eterm,is_external);
-ET_DEFINE_CHECKED(Uint,external_pid_data_words,Eterm,is_external_pid);
-ET_DEFINE_CHECKED(Uint,external_pid_data,Eterm,is_external_pid);
-ET_DEFINE_CHECKED(struct erl_node_*,external_pid_node,Eterm,is_external_pid);
-ET_DEFINE_CHECKED(Uint,external_port_data_words,Eterm,is_external_port);
-ET_DEFINE_CHECKED(Uint,external_port_data,Eterm,is_external_port);
-ET_DEFINE_CHECKED(struct erl_node_*,external_port_node,Eterm,is_external_port);
-ET_DEFINE_CHECKED(Uint,external_ref_data_words,Eterm,is_external_ref);
-ET_DEFINE_CHECKED(Uint32*,external_ref_data,Eterm,is_external_ref);
+ET_DEFINE_CHECKED(Eterm*,external_val,Wterm,is_external);
+ET_DEFINE_CHECKED(Uint,external_data_words,Wterm,is_external);
+ET_DEFINE_CHECKED(Uint,external_pid_data_words,Wterm,is_external_pid);
+ET_DEFINE_CHECKED(Uint,external_pid_data,Wterm,is_external_pid);
+ET_DEFINE_CHECKED(struct erl_node_*,external_pid_node,Wterm,is_external_pid);
+ET_DEFINE_CHECKED(Uint,external_port_data_words,Wterm,is_external_port);
+ET_DEFINE_CHECKED(Uint,external_port_data,Wterm,is_external_port);
+ET_DEFINE_CHECKED(struct erl_node_*,external_port_node,Wterm,is_external_port);
+ET_DEFINE_CHECKED(Uint,external_ref_data_words,Wterm,is_external_ref);
+ET_DEFINE_CHECKED(Uint32*,external_ref_data,Wterm,is_external_ref);
 ET_DEFINE_CHECKED(struct erl_node_*,external_ref_node,Eterm,is_external_ref);
-ET_DEFINE_CHECKED(Eterm*,export_val,Eterm,is_export);
+ET_DEFINE_CHECKED(Eterm*,export_val,Wterm,is_export);
+ET_DEFINE_CHECKED(Uint,external_thing_data_words,ExternalThing*,is_thing_ptr);
 
 ET_DEFINE_CHECKED(Eterm,make_cp,UWord *,_is_taggable_pointer);
 ET_DEFINE_CHECKED(UWord *,cp_val,Eterm,is_CP);
diff --git a/erts/emulator/beam/erl_term.h b/erts/emulator/beam/erl_term.h
index 815cc1beae..1225b6a944 100644
--- a/erts/emulator/beam/erl_term.h
+++ b/erts/emulator/beam/erl_term.h
@@ -22,6 +22,8 @@
 
 #include "sys.h" /* defines HALFWORD_HEAP */
 
+typedef UWord Wterm;  /* Full word terms */
+
 #if HALFWORD_HEAP
 #  define HEAP_ON_C_STACK 0
 #  if HALFWORD_ASSERT
@@ -204,7 +206,7 @@ _ET_DECLARE_CHECKED(int,is_boxed,Eterm)
 #define is_boxed(x)		(((x) & _TAG_PRIMARY_MASK) == TAG_PRIMARY_BOXED)
 #endif
 #define _unchecked_boxed_val(x) ((Eterm*) EXPAND_POINTER(((x) - TAG_PRIMARY_BOXED)))
-_ET_DECLARE_CHECKED(Eterm*,boxed_val,Eterm)
+_ET_DECLARE_CHECKED(Eterm*,boxed_val,Wterm)
 #define boxed_val(x)		_ET_APPLY(boxed_val,(x))
 
 /* cons cell ("list") access methods */
@@ -226,7 +228,7 @@ _ET_DECLARE_CHECKED(int,is_not_list,Eterm)
 #define _list_precond(x)       (is_list(x))
 #endif
 #define _unchecked_list_val(x) ((Eterm*) EXPAND_POINTER((x) - TAG_PRIMARY_LIST))
-_ET_DECLARE_CHECKED(Eterm*,list_val,Eterm)
+_ET_DECLARE_CHECKED(Eterm*,list_val,Wterm)
 #define list_val(x)		_ET_APPLY(list_val,(x))
 
 #define CONS(hp, car, cdr) \
@@ -240,6 +242,8 @@ _ET_DECLARE_CHECKED(Eterm*,list_val,Eterm)
 #define ptr_val(x)		_unchecked_ptr_val((x))	/*XXX*/
 #define _unchecked_offset_ptr(x,offs)	((x)+((offs)*sizeof(Eterm)))
 #define offset_ptr(x,offs)	_unchecked_offset_ptr(x,offs)	/*XXX*/
+#define _unchecked_byte_offset_ptr(x,byte_offs)	((x)+(offs))
+#define byte_offset_ptr(x,offs) _unchecked_byte_offset_ptr(x,offs)  /*XXX*/
 
 /* fixnum ("small") access methods */
 #if defined(ARCH_64) && !HALFWORD_HEAP
@@ -305,6 +309,7 @@ _ET_DECLARE_CHECKED(Uint,arityval,Eterm)
 
 /* thing access methods */
 #define is_thing(x)	(is_header((x)) && header_is_thing((x)))
+#define is_thing_ptr(t) (is_thing((t)->header))
 #define _unchecked_thing_arityval(x)	_unchecked_header_arity((x))
 _ET_DECLARE_CHECKED(Uint,thing_arityval,Eterm)
 #define thing_arityval(x)	_ET_APPLY(thing_arityval,(x))
@@ -339,7 +344,7 @@ _ET_DECLARE_CHECKED(Uint,thing_subtag,Eterm)
 #define is_binary(x)	(is_boxed((x)) && is_binary_header(*boxed_val((x))))
 #define is_not_binary(x) (!is_binary((x)))
 #define _unchecked_binary_val(x) _unchecked_boxed_val((x))
-_ET_DECLARE_CHECKED(Eterm*,binary_val,Eterm)
+_ET_DECLARE_CHECKED(Eterm*,binary_val,Wterm)
 #define binary_val(x)	_ET_APPLY(binary_val,(x))
 
 /* process binaries stuff (special case of binaries) */
@@ -354,17 +359,19 @@ _ET_DECLARE_CHECKED(Eterm*,binary_val,Eterm)
 #define is_fun_header(x)	((x) == HEADER_FUN)
 #define make_fun(x)		make_boxed((Eterm*)(x))
 #define is_fun(x)		(is_boxed((x)) && is_fun_header(*boxed_val((x))))
+#define is_fun_rel(x,Base)	(is_boxed((x)) && is_fun_header(*boxed_val_rel((x),Base)))
 #define is_not_fun(x)		(!is_fun((x)))
 #define _unchecked_fun_val(x)   _unchecked_boxed_val((x))
-_ET_DECLARE_CHECKED(Eterm*,fun_val,Eterm)
+_ET_DECLARE_CHECKED(Eterm*,fun_val,Wterm)
 #define fun_val(x)		_ET_APPLY(fun_val,(x))
 
 /* export access methods */
 #define make_export(x)	 make_boxed((x))
 #define is_export(x)     (is_boxed((x)) && is_export_header(*boxed_val((x))))
+#define is_export_rel(x,Base)     (is_boxed((x)) && is_export_header(*boxed_val_rel((x),Base)))
 #define is_not_export(x) (!is_export((x)))
 #define _unchecked_export_val(x)   _unchecked_boxed_val(x)
-_ET_DECLARE_CHECKED(Eterm*,export_val,Eterm)
+_ET_DECLARE_CHECKED(Eterm*,export_val,Wterm)
 #define export_val(x)	_ET_APPLY(export_val,(x))
 #define is_export_header(x)	((x) == HEADER_EXPORT)
 #if HALFWORD_HEAP
@@ -389,9 +396,10 @@ _ET_DECLARE_CHECKED(Uint,bignum_header_arity,Eterm)
 #define BIG_ARITY_MAX		((1 << 19)-1)
 #define make_big(x)	make_boxed((x))
 #define is_big(x)	(is_boxed((x)) && _is_bignum_header(*boxed_val((x))))
+#define is_big_rel(x,Base) (is_boxed((x)) && _is_bignum_header(*boxed_val_rel((x),Base)))
 #define is_not_big(x)	(!is_big((x)))
 #define _unchecked_big_val(x)	_unchecked_boxed_val((x))
-_ET_DECLARE_CHECKED(Eterm*,big_val,Eterm)
+_ET_DECLARE_CHECKED(Eterm*,big_val,Wterm)
 #define big_val(x)		_ET_APPLY(big_val,(x))
 
 /* flonum ("float") access methods */
@@ -402,9 +410,10 @@ _ET_DECLARE_CHECKED(Eterm*,big_val,Eterm)
 #endif
 #define make_float(x)	make_boxed((x))
 #define is_float(x)	(is_boxed((x)) && *boxed_val((x)) == HEADER_FLONUM)
+#define is_float_rel(x,Base) (is_boxed((x)) && *boxed_val_rel((x),Base) == HEADER_FLONUM)
 #define is_not_float(x)	(!is_float(x))
 #define _unchecked_float_val(x)	_unchecked_boxed_val((x))
-_ET_DECLARE_CHECKED(Eterm*,float_val,Eterm)
+_ET_DECLARE_CHECKED(Eterm*,float_val,Wterm)
 #define float_val(x)	_ET_APPLY(float_val,(x))
 
 /* Float definition for byte and word access */
@@ -422,15 +431,16 @@ typedef union float_def
 } FloatDef;
 
 #if defined(ARCH_64) && !HALFWORD_HEAP
-#define GET_DOUBLE(x, f) (f).fdw = *(float_val(x)+1)
+
+#define FLOAT_VAL_GET_DOUBLE(fval, f) (f).fdw = *((fval)+1)
 
 #define PUT_DOUBLE(f, x)  *(x) = HEADER_FLONUM, \
                           *((x)+1) = (f).fdw
 #define GET_DOUBLE_DATA(p, f) (f).fdw = *((Uint *) (p))
 #define PUT_DOUBLE_DATA(f,p) *((Uint *) (p)) = (f).fdw
 #else
-#define GET_DOUBLE(x, f) (f).fw[0] = *(float_val(x)+1), \
-                         (f).fw[1] = *(float_val(x)+2)
+#define FLOAT_VAL_GET_DOUBLE(fval, f) (f).fw[0] = *((fval)+1), \
+				      (f).fw[1] = *((fval)+2)
 
 #define PUT_DOUBLE(f, x)  *(x) = HEADER_FLONUM, \
                           *((x)+1) = (f).fw[0], \
@@ -440,18 +450,23 @@ typedef union float_def
 #define PUT_DOUBLE_DATA(f,p) *((Uint *) (p)) = (f).fw[0],\
                              *(((Uint *) (p))+1) = (f).fw[1]
 #endif
+
+#define GET_DOUBLE(x, f) FLOAT_VAL_GET_DOUBLE(float_val(x),f)
+#define GET_DOUBLE_REL(x, f, Base) FLOAT_VAL_GET_DOUBLE(float_val_rel(x,Base),f)
+
 #define DOUBLE_DATA_WORDS (sizeof(ieee754_8)/sizeof(Eterm))
 #define FLOAT_SIZE_OBJECT (DOUBLE_DATA_WORDS+1)
 
 /* tuple access methods */
 #define make_tuple(x)	make_boxed((x))
 #define is_tuple(x)	(is_boxed((x)) && is_arity_value(*boxed_val((x))))
+#define is_tuple_rel(x,Base) (is_boxed((x)) && is_arity_value(*boxed_val_rel((x),Base)))
 #define is_not_tuple(x)	(!is_tuple((x)))
 #define is_tuple_arity(x, a) \
    (is_boxed((x)) && *boxed_val((x)) == make_arityval((a)))
 #define is_not_tuple_arity(x, a) (!is_tuple_arity((x),(a)))
 #define _unchecked_tuple_val(x)	_unchecked_boxed_val(x)
-_ET_DECLARE_CHECKED(Eterm*,tuple_val,Eterm)
+_ET_DECLARE_CHECKED(Eterm*,tuple_val,Wterm)
 #define tuple_val(x)	_ET_APPLY(tuple_val,(x))
 
 #define TUPLE0(t) \
@@ -788,23 +803,30 @@ do {									\
   ((RefThing*) _unchecked_internal_ref_val(x))
 #define ref_thing_ptr(x) \
   ((RefThing*) internal_ref_val(x))
+#define ref_thing_ptr_rel(x,Base) \
+  ((RefThing*) internal_ref_val_rel(x,Base))
+
 
 #define is_internal_ref(x) \
   (_unchecked_is_boxed((x)) && is_ref_thing_header(*boxed_val((x))))
+#define is_internal_ref_rel(x,Base) \
+  (_unchecked_is_boxed((x)) && is_ref_thing_header(*boxed_val_rel((x),Base)))
 #define is_not_internal_ref(x) \
   (!is_internal_ref((x)))
 
 #define _unchecked_internal_ref_val(x) _unchecked_boxed_val((x))
-_ET_DECLARE_CHECKED(Eterm*,internal_ref_val,Eterm)
+_ET_DECLARE_CHECKED(Eterm*,internal_ref_val,Wterm)
 #define internal_ref_val(x) _ET_APPLY(internal_ref_val,(x))
 
+#define internal_thing_ref_data_words(t) (thing_arityval(*(Eterm*)(t)))
 #define _unchecked_internal_ref_data_words(x) \
  (_unchecked_thing_arityval(*_unchecked_internal_ref_val(x)))
-_ET_DECLARE_CHECKED(Uint,internal_ref_data_words,Eterm)
+_ET_DECLARE_CHECKED(Uint,internal_ref_data_words,Wterm)
 #define internal_ref_data_words(x) _ET_APPLY(internal_ref_data_words,(x))
 
-#define _unchecked_internal_ref_data(x) (_unchecked_ref_thing_ptr(x)->data.ui32)
-_ET_DECLARE_CHECKED(Uint32*,internal_ref_data,Eterm)
+#define internal_thing_ref_data(thing) ((thing)->data.ui32)
+#define _unchecked_internal_ref_data(x) (internal_thing_ref_data(_unchecked_ref_thing_ptr(x)))
+_ET_DECLARE_CHECKED(Uint32*,internal_ref_data,Wterm)
 #define internal_ref_data(x) _ET_APPLY(internal_ref_data,(x))
 
 #define _unchecked_internal_ref_node(x) erts_this_node
@@ -891,12 +913,18 @@ typedef struct external_thing_ {
 
 #define is_external(x) \
   (is_boxed((x)) && is_external_header(*boxed_val((x))))
+#define is_external_rel(x,Base) \
+  (is_boxed((x)) && is_external_header(*boxed_val_rel((x),Base)))
 #define is_external_pid(x) \
   (is_boxed((x)) && is_external_pid_header(*boxed_val((x))))
 #define is_external_port(x) \
   (is_boxed((x)) && is_external_port_header(*boxed_val((x))))
+#define is_external_port_rel(x,Base) \
+  (is_boxed((x)) && is_external_port_header(*boxed_val_rel((x),Base)))
 #define is_external_ref(x) \
   (_unchecked_is_boxed((x)) && is_external_ref_header(*boxed_val((x))))
+#define is_external_ref_rel(x,Base) \
+  (_unchecked_is_boxed((x)) && is_external_ref_header(*boxed_val_rel((x),Base)))
 
 #define _unchecked_is_external(x) \
   (_unchecked_is_boxed((x)) && is_external_header(*_unchecked_boxed_val((x))))
@@ -914,36 +942,43 @@ typedef struct external_thing_ {
 #define make_external_ref		make_external
 
 #define _unchecked_external_val(x) _unchecked_boxed_val((x))
-_ET_DECLARE_CHECKED(Eterm*,external_val,Eterm)
+_ET_DECLARE_CHECKED(Eterm*,external_val,Wterm)
 #define external_val(x) _ET_APPLY(external_val,(x))
 
 #define external_thing_ptr(x) ((ExternalThing *) external_val((x)))
 #define _unchecked_external_thing_ptr(x) \
   ((ExternalThing *) _unchecked_external_val((x)))
 
+#define _unchecked_external_thing_data_words(thing) \
+    (_unchecked_thing_arityval((thing)->header) + (1 - EXTERNAL_THING_HEAD_SIZE))
+_ET_DECLARE_CHECKED(Uint,external_thing_data_words,ExternalThing*)
+#define external_thing_data_words(thing) _ET_APPLY(external_thing_data_words,(thing))
+
 #define _unchecked_external_data_words(x) \
-  (_unchecked_thing_arityval(_unchecked_external_thing_ptr((x))->header) \
-   + (1 - EXTERNAL_THING_HEAD_SIZE))
-_ET_DECLARE_CHECKED(Uint,external_data_words,Eterm)
+    _unchecked_external_thing_data_words(_unchecked_external_thing_ptr((x)))
+_ET_DECLARE_CHECKED(Uint,external_data_words,Wterm)
 #define external_data_words(x) _ET_APPLY(external_data_words,(x))
+#define external_data_words_rel(x,Base) \
+    external_thing_data_words(external_thing_ptr_rel((x),Base))
 
 #define _unchecked_external_data(x) (_unchecked_external_thing_ptr((x))->data.ui)
 #define _unchecked_external_node(x) (_unchecked_external_thing_ptr((x))->node)
 
 #define external_data(x) (external_thing_ptr((x))->data.ui)
 #define external_node(x) (external_thing_ptr((x))->node)
+#define external_node_rel(x,Base) (external_thing_ptr_rel((x),Base)->node)
 
 #define _unchecked_external_pid_data_words(x) \
   _unchecked_external_data_words((x))
-_ET_DECLARE_CHECKED(Uint,external_pid_data_words,Eterm)
+_ET_DECLARE_CHECKED(Uint,external_pid_data_words,Wterm)
 #define external_pid_data_words(x) _ET_APPLY(external_pid_data_words,(x))
 
 #define _unchecked_external_pid_data(x) _unchecked_external_data((x))[0]
-_ET_DECLARE_CHECKED(Uint,external_pid_data,Eterm)
+_ET_DECLARE_CHECKED(Uint,external_pid_data,Wterm)
 #define external_pid_data(x) _ET_APPLY(external_pid_data,(x))
 
 #define _unchecked_external_pid_node(x) _unchecked_external_node((x))
-_ET_DECLARE_CHECKED(struct erl_node_*,external_pid_node,Eterm)
+_ET_DECLARE_CHECKED(struct erl_node_*,external_pid_node,Wterm)
 #define external_pid_node(x) _ET_APPLY(external_pid_node,(x))
 
 #define external_pid_number(x) _GET_PID_NUM(external_pid_data((x)))
@@ -951,27 +986,29 @@ _ET_DECLARE_CHECKED(struct erl_node_*,external_pid_node,Eterm)
 
 #define _unchecked_external_port_data_words(x) \
   _unchecked_external_data_words((x))
-_ET_DECLARE_CHECKED(Uint,external_port_data_words,Eterm)
+_ET_DECLARE_CHECKED(Uint,external_port_data_words,Wterm)
 #define external_port_data_words(x) _ET_APPLY(external_port_data_words,(x))
 
 #define _unchecked_external_port_data(x) _unchecked_external_data((x))[0]
-_ET_DECLARE_CHECKED(Uint,external_port_data,Eterm)
+_ET_DECLARE_CHECKED(Uint,external_port_data,Wterm)
 #define external_port_data(x) _ET_APPLY(external_port_data,(x))
 
 #define _unchecked_external_port_node(x) _unchecked_external_node((x))
-_ET_DECLARE_CHECKED(struct erl_node_*,external_port_node,Eterm)
+_ET_DECLARE_CHECKED(struct erl_node_*,external_port_node,Wterm)
 #define external_port_node(x) _ET_APPLY(external_port_node,(x))
 
 #define external_port_number(x) _GET_PORT_NUM(external_port_data((x)))
 
 #define _unchecked_external_ref_data_words(x) \
   _unchecked_external_data_words((x))
-_ET_DECLARE_CHECKED(Uint,external_ref_data_words,Eterm)
+_ET_DECLARE_CHECKED(Uint,external_ref_data_words,Wterm)
 #define external_ref_data_words(x) _ET_APPLY(external_ref_data_words,(x))
+#define external_thing_ref_data_words(thing) external_thing_data_words(thing)
 
 #define _unchecked_external_ref_data(x) (_unchecked_external_thing_ptr((x))->data.ui32)
-_ET_DECLARE_CHECKED(Uint32*,external_ref_data,Eterm)
+_ET_DECLARE_CHECKED(Uint32*,external_ref_data,Wterm)
 #define external_ref_data(x) _ET_APPLY(external_ref_data,(x))
+#define external_thing_ref_data(thing) ((thing)->data.ui32)
 
 #define _unchecked_external_ref_node(x) _unchecked_external_node((x))
 _ET_DECLARE_CHECKED(struct erl_node_*,external_ref_node,Eterm)
@@ -1083,10 +1120,10 @@ _ET_DECLARE_CHECKED(Uint,y_reg_index,Uint)
 #define SMALL_DEF		0xf
 
 #if ET_DEBUG
-extern unsigned tag_val_def_debug(Eterm, const char*, unsigned);
+extern unsigned tag_val_def_debug(Wterm, const char*, unsigned);
 #define tag_val_def(x)	tag_val_def_debug((x),__FILE__,__LINE__)
 #else
-extern unsigned tag_val_def(Eterm);
+extern unsigned tag_val_def(Wterm);
 #endif
 #define not_eq_tags(X,Y)	(tag_val_def((X)) ^ tag_val_def((Y)))
 
@@ -1102,5 +1139,64 @@ extern unsigned tag_val_def(Eterm);
 #define FLOAT_BIG 	_NUMBER_CODE(FLOAT_DEF,BIG_DEF)
 #define FLOAT_FLOAT	_NUMBER_CODE(FLOAT_DEF,FLOAT_DEF)
 
+#if HALFWORD_HEAP
+#define ptr2rel(PTR,BASE) ((Eterm*)((char*)(PTR) - (char*)(BASE)))
+#define rel2ptr(REL,BASE) ((typeof(REL)) ((UWord)(REL) + (char*)(BASE)))
+#define rterm2wterm(REL,BASE) ((Wterm)(REL) + (Wterm)(BASE))
+
+#else /* HALFWORD_HEAP */
+
+#define ptr2rel(PTR,BASE) (PTR)
+#define rel2ptr(REL,BASE) (REL)
+#define rterm2wterm(REL,BASE) (REL)
+
+#endif /* !HALFWORD_HEAP */
+
+#define make_list_rel(PTR, BASE) make_list(ptr2rel(PTR,BASE))
+#define make_boxed_rel(PTR, BASE) make_boxed(ptr2rel(PTR,BASE))
+#define make_fun_rel make_boxed_rel
+#define make_binary_rel make_boxed_rel
+#define make_tuple_rel make_boxed_rel
+#define make_external_rel make_boxed_rel
+
+#define binary_val_rel(RTERM, BASE) binary_val(rterm2wterm(RTERM, BASE))
+#define list_val_rel(RTERM, BASE) list_val(rterm2wterm(RTERM, BASE))
+#define boxed_val_rel(RTERM, BASE) boxed_val(rterm2wterm(RTERM, BASE))
+#define tuple_val_rel(RTERM, BASE) tuple_val(rterm2wterm(RTERM, BASE))
+#define export_val_rel(RTERM, BASE) export_val(rterm2wterm(RTERM, BASE))
+#define fun_val_rel(RTERM, BASE) fun_val(rterm2wterm(RTERM, BASE))
+#define big_val_rel(RTERM,BASE)	big_val(rterm2wterm(RTERM,BASE))
+#define float_val_rel(RTERM,BASE) float_val(rterm2wterm(RTERM,BASE))
+#define internal_ref_val_rel(RTERM,BASE) internal_ref_val(rterm2wterm(RTERM,BASE))
+
+#define external_thing_ptr_rel(RTERM, BASE) external_thing_ptr(rterm2wterm(RTERM, BASE))
+#define external_port_node_rel(RTERM,BASE) external_port_node(rterm2wterm(RTERM,BASE))
+#define external_port_data_rel(RTERM,BASE) external_port_data(rterm2wterm(RTERM,BASE))
+
+#define is_external_pid_rel(RTERM,BASE) is_external_pid(rterm2wterm(RTERM,BASE))
+#define external_pid_node_rel(RTERM,BASE) external_pid_node(rterm2wterm(RTERM,BASE))
+#define external_pid_data_rel(RTERM,BASE) external_pid_data(rterm2wterm(RTERM,BASE))
+
+#define is_binary_rel(RTERM,BASE) is_binary(rterm2wterm(RTERM,BASE))
+
+#if HALFWORD_HEAP
+ERTS_GLB_INLINE int is_same(Eterm a, Eterm* a_base, Eterm b, Eterm* b_base);
+
+#if ERTS_GLB_INLINE_INCL_FUNC_DEF
+ERTS_GLB_INLINE int is_same(Eterm a, Eterm* a_base, Eterm b, Eterm* b_base)
+{
+    if (a_base == b_base) {
+	return a == b;
+    }
+    /* Assume a and b are on different "heaps", ie can only be same if immed */
+    ASSERT(is_immed(a) || is_immed(b) || rterm2wterm(a,a_base) != rterm2wterm(b,b_base));
+    return is_immed(a) && a == b;
+}
+#endif
+
+#else /* !HALFWORD_HEAP */
+#define is_same(A,A_BASE,B,B_BASE) ((A)==(B))
+#endif
+
 #endif	/* __ERL_TERM_H */
 
diff --git a/erts/emulator/beam/global.h b/erts/emulator/beam/global.h
index e8a9d5f32f..1516d08299 100644
--- a/erts/emulator/beam/global.h
+++ b/erts/emulator/beam/global.h
@@ -890,9 +890,31 @@ void erl_error(char*, va_list);
 /* copy.c */
 void init_copy(void);
 Eterm copy_object(Eterm, Process*);
+
+#if HALFWORD_HEAP
+Uint size_object_rel(Eterm, Eterm*);
+#  define size_object(A) size_object_rel(A,NULL)
+
+Eterm copy_struct_rel(Eterm, Uint, Eterm**, ErlOffHeap*, Eterm* src_base, Eterm* dst_base);
+#  define copy_struct(OBJ,SZ,HPP,OH) copy_struct_rel(OBJ,SZ,HPP,OH, NULL,NULL)
+
+Eterm copy_shallow_rel(Eterm*, Uint, Eterm**, ErlOffHeap*, Eterm* src_base);
+#  define copy_shallow(A,B,C,D) copy_shallow_rel(A,B,C,D,NULL)
+
+#else /* HALFWORD_HEAP */
+
 Uint size_object(Eterm);
+#  define size_object_rel(A,B) size_object(A)
+
 Eterm copy_struct(Eterm, Uint, Eterm**, ErlOffHeap*);
+#  define copy_struct_rel(OBJ,SZ,HPP,OH, SB,DB) copy_struct(OBJ,SZ,HPP,OH)
+
 Eterm copy_shallow(Eterm*, Uint, Eterm**, ErlOffHeap*);
+#  define copy_shallow_rel(A,B,C,D, BASE) copy_shallow(A,B,C,D)
+
+#endif
+
+
 void move_multi_frags(Eterm** hpp, ErlOffHeap*, ErlHeapFragment* first,
 		      Eterm* refs, unsigned nrefs);
 
@@ -1483,16 +1505,30 @@ void erts_init_utils_mem(void);
 erts_dsprintf_buf_t *erts_create_tmp_dsbuf(Uint);
 void erts_destroy_tmp_dsbuf(erts_dsprintf_buf_t *);
 
+#if HALFWORD_HEAP
+int eq_rel(Eterm a, Eterm b, Eterm* b_base);
+#  define eq(A,B) eq_rel(A,B,NULL)
+#else
 int eq(Eterm, Eterm);
+#  define eq_rel(A,B,B_BASE) eq(A,B)
+#endif
+
 #define EQ(x,y) (((x) == (y)) || (is_not_both_immed((x),(y)) && eq((x),(y))))
 
+#if HALFWORD_HEAP
+Sint cmp_rel(Eterm, Eterm*, Eterm, Eterm*);
+#define CMP(A,B) cmp_rel(A,NULL,B,NULL)
+#else
 Sint cmp(Eterm, Eterm);
-#define cmp_lt(a,b)	(cmp((a),(b)) < 0)
-#define cmp_le(a,b)	(cmp((a),(b)) <= 0)
-#define cmp_eq(a,b)	(cmp((a),(b)) == 0)
-#define cmp_ne(a,b)	(cmp((a),(b)) != 0)
-#define cmp_ge(a,b)	(cmp((a),(b)) >= 0)
-#define cmp_gt(a,b)	(cmp((a),(b)) > 0)
+#define cmp_rel(A,A_BASE,B,B_BASE) cmp(A,B)
+#define CMP(A,B) cmp(A,B)
+#endif
+#define cmp_lt(a,b)	(CMP((a),(b)) < 0)
+#define cmp_le(a,b)	(CMP((a),(b)) <= 0)
+#define cmp_eq(a,b)	(CMP((a),(b)) == 0)
+#define cmp_ne(a,b)	(CMP((a),(b)) != 0)
+#define cmp_ge(a,b)	(CMP((a),(b)) >= 0)
+#define cmp_gt(a,b)	(CMP((a),(b)) > 0)
 
 #define CMP_LT(a,b)	((a) != (b) && cmp_lt((a),(b)))
 #define CMP_GE(a,b)	((a) == (b) || cmp_ge((a),(b)))
diff --git a/erts/emulator/beam/utils.c b/erts/emulator/beam/utils.c
index 1d60b54d21..9cdd46f27a 100644
--- a/erts/emulator/beam/utils.c
+++ b/erts/emulator/beam/utils.c
@@ -1894,15 +1894,17 @@ erts_destroy_tmp_dsbuf(erts_dsprintf_buf_t *dsbufp)
     erts_free(ERTS_ALC_T_TMP_DSBUF, (void *) dsbufp);
 }
 
-
 /* eq and cmp are written as separate functions a eq is a little faster */
 
 /*
  * Test for equality of two terms.
  * Returns 0 if not equal, or a non-zero value otherwise.
  */
-
+#if HALFWORD_HEAP
+int eq_rel(Eterm a, Eterm b, Eterm* b_base)
+#else
 int eq(Eterm a, Eterm b)
+#endif
 {
     DECLARE_WSTACK(stack);
     Sint sz;
@@ -1910,18 +1912,18 @@ int eq(Eterm a, Eterm b)
     Eterm* bb;	
 
 tailrecur:
-    if (a == b) goto pop_next; 
+    if (is_same(a,NULL, b,b_base)) goto pop_next;
 tailrecur_ne:
 
     switch (primary_tag(a)) {
     case TAG_PRIMARY_LIST:
 	if (is_list(b)) {
 	    Eterm* aval = list_val(a);
-	    Eterm* bval = list_val(b);
+	    Eterm* bval = list_val_rel(b, b_base);
 	    while (1) {
 		Eterm atmp = CAR(aval);
 		Eterm btmp = CAR(bval);
-		if (atmp != btmp) {
+		if (!is_same(atmp,NULL,btmp,b_base)) {
 		    WSTACK_PUSH2(stack,(UWord) CDR(bval),(UWord) CDR(aval));
 		    a = atmp;
 		    b = btmp;
@@ -1929,7 +1931,7 @@ tailrecur_ne:
 		}
 		atmp = CDR(aval);
 		btmp = CDR(bval);
-		if (atmp == btmp) {
+		if (is_same(atmp,NULL,btmp,b_base)) {
 		    goto pop_next;
 		}
 		if (is_not_list(atmp) || is_not_list(btmp)) {
@@ -1938,7 +1940,7 @@ tailrecur_ne:
 		    goto tailrecur_ne;
 		}
 		aval = list_val(atmp);
-		bval = list_val(btmp);
+		bval = list_val_rel(btmp, b_base);
 	    }
 	}
 	break; /* not equal */
@@ -1950,9 +1952,9 @@ tailrecur_ne:
 	    case ARITYVAL_SUBTAG:
 		{
 		    aa = tuple_val(a);
-		    if (!is_boxed(b) || *boxed_val(b) != *aa)
+		    if (!is_boxed(b) || *boxed_val_rel(b,b_base) != *aa)
 			goto not_equal;
-		    bb = tuple_val(b);
+		    bb = tuple_val_rel(b,b_base);
 		    if ((sz = arityval(*aa)) == 0) goto pop_next;
 		    ++aa;
 		    ++bb;
@@ -1971,16 +1973,16 @@ tailrecur_ne:
 		    Uint a_bitoffs;
 		    Uint b_bitoffs;
 		    
-		    if (is_not_binary(b)) {
+		    if (!is_binary_rel(b,b_base)) {
 			goto not_equal;
 		    }
 		    a_size = binary_size(a);
-		    b_size = binary_size(b); 
+		    b_size = binary_size_rel(b,b_base);
 		    if (a_size != b_size) {
 			goto not_equal;
 		    }
 		    ERTS_GET_BINARY_BYTES(a, a_ptr, a_bitoffs, a_bitsize);
-		    ERTS_GET_BINARY_BYTES(b, b_ptr, b_bitoffs, b_bitsize);
+		    ERTS_GET_BINARY_BYTES_REL(b, b_ptr, b_bitoffs, b_bitsize, b_base);
 		    if ((a_bitsize | b_bitsize | a_bitoffs | b_bitoffs) == 0) {
 			if (sys_memcmp(a_ptr, b_ptr, a_size) == 0) goto pop_next;
 		    } else if (a_bitsize == b_bitsize) {
@@ -1991,9 +1993,9 @@ tailrecur_ne:
 		}
 	    case EXPORT_SUBTAG:
 		{
-		    if (is_export(b)) {
+		    if (is_export_rel(b,b_base)) {
 			Export* a_exp = *((Export **) (export_val(a) + 1));
-			Export* b_exp = *((Export **) (export_val(b) + 1));
+			Export* b_exp = *((Export **) (export_val_rel(b,b_base) + 1));
 			if (a_exp == b_exp) goto pop_next;
 		    }
 		    break; /* not equal */
@@ -2003,10 +2005,10 @@ tailrecur_ne:
 		    ErlFunThing* f1;
 		    ErlFunThing* f2;
   
-		    if (is_not_fun(b))
+		    if (!is_fun_rel(b,b_base))
 			goto not_equal;
 		    f1 = (ErlFunThing *) fun_val(a);
-		    f2 = (ErlFunThing *) fun_val(b);
+		    f2 = (ErlFunThing *) fun_val_rel(b,b_base);
 		    if (f1->fe->module != f2->fe->module ||
 			f1->fe->old_index != f2->fe->old_index ||
 			f1->fe->old_uniq != f2->fe->old_uniq ||
@@ -2024,15 +2026,15 @@ tailrecur_ne:
 		ExternalThing *ap;
 		ExternalThing *bp;
 
-		if(is_not_external(b))
+		if(!is_external_rel(b,b_base))
 		    goto not_equal;
 
 		ap = external_thing_ptr(a);
-		bp = external_thing_ptr(b);
+		bp = external_thing_ptr_rel(b,b_base);
 
 		if(ap->header == bp->header && ap->node == bp->node) {
 		    ASSERT(1 == external_data_words(a));
-		    ASSERT(1 == external_data_words(b));
+		    ASSERT(1 == external_data_words_rel(b,b_base));
 		    
 		    if (ap->data.ui[0] == bp->data.ui[0]) goto pop_next;
 		}
@@ -2050,27 +2052,36 @@ tailrecur_ne:
 		Uint alen;
 		Uint blen;
 		Uint i;
+		ExternalThing* athing;
+		ExternalThing* bthing;
 
-		if(is_not_external_ref(b))
+		if(!is_external_ref_rel(b,b_base))
 		    goto not_equal;
 
-		if(external_node(a) != external_node(b))
+		athing = external_thing_ptr(a);
+		bthing = external_thing_ptr_rel(b,b_base);
+
+		if(athing->node != bthing->node)
 		    goto not_equal;
 
-		anum = external_ref_numbers(a);
-		bnum = external_ref_numbers(b);
-		alen = external_ref_no_of_numbers(a);
-		blen = external_ref_no_of_numbers(b);
+		anum = external_thing_ref_numbers(athing);
+		bnum = external_thing_ref_numbers(bthing);
+		alen = external_thing_ref_no_of_numbers(athing);
+		blen = external_thing_ref_no_of_numbers(bthing);
 
 		goto ref_common;
 	    case REF_SUBTAG:
-  
-		    if (is_not_internal_ref(b))
+		    if (!is_internal_ref_rel(b,b_base))
 			goto not_equal;
-		    alen = internal_ref_no_of_numbers(a);
-		    blen = internal_ref_no_of_numbers(b);
-		    anum = internal_ref_numbers(a);
-		    bnum = internal_ref_numbers(b);
+
+		    {
+			RefThing* athing = ref_thing_ptr(a);
+			RefThing* bthing = ref_thing_ptr_rel(b,b_base);
+			alen = internal_thing_ref_no_of_numbers(athing);
+			blen = internal_thing_ref_no_of_numbers(bthing);
+			anum = internal_thing_ref_numbers(athing);
+			bnum = internal_thing_ref_numbers(bthing);
+		    }
 
 	    ref_common:
 		    ASSERT(alen > 0 && blen > 0);
@@ -2115,10 +2126,10 @@ tailrecur_ne:
 		{
 		    int i;
   
-		    if (is_not_big(b))
+		    if (!is_big_rel(b,b_base))
 			goto not_equal;
 		    aa = big_val(a); /* get pointer to thing */
-		    bb = big_val(b);
+		    bb = big_val_rel(b,b_base);
 		    if (*aa != *bb)
 			goto not_equal;
 		    i = BIG_ARITY(aa);
@@ -2133,9 +2144,9 @@ tailrecur_ne:
 		    FloatDef af;
 		    FloatDef bf;
   
-		    if (is_float(b)) {
+		    if (is_float_rel(b,b_base)) {
 			GET_DOUBLE(a, af);
-			GET_DOUBLE(b, bf);
+			GET_DOUBLE_REL(b, bf, b_base);
 			if (af.fd == bf.fd) goto pop_next;
 		    }
 		    break; /* not equal */
@@ -2154,7 +2165,7 @@ term_array: /* arrays in 'aa' and 'bb', length in 'sz' */
 	Eterm* bp = bb;
 	Sint i = sz;
 	for (;;) {
-	    if (*ap != *bp) break;
+	    if (!is_same(*ap,NULL,*bp,b_base)) break;
 	    if (--i == 0) goto pop_next;
 	    ++ap;
 	    ++bp;
@@ -2243,7 +2254,11 @@ static int cmp_atoms(Eterm a, Eterm b)
 		    bb->name+3, bb->len-3);
 }
 
+#if HALFWORD_HEAP
+Sint cmp_rel(Eterm a, Eterm* a_base, Eterm b, Eterm* b_base)
+#else
 Sint cmp(Eterm a, Eterm b)
+#endif
 {
     DECLARE_WSTACK(stack);
     Eterm* aa;
@@ -2277,7 +2292,7 @@ Sint cmp(Eterm a, Eterm b)
 
 
 tailrecur:
-    if (a == b) {		/* Equal values or pointers. */
+    if (is_same(a,a_base,b,b_base)) {	/* Equal values or pointers. */
 	goto pop_next;
     }
 tailrecur_ne:
@@ -2303,9 +2318,9 @@ tailrecur_ne:
 	    if (is_internal_port(b)) {
 		bnode = erts_this_node;
 		bdata = internal_port_data(b);
-	    } else if (is_external_port(b)) {
-		bnode = external_port_node(b);
-		bdata = external_port_data(b);
+	    } else if (is_external_port_rel(b,b_base)) {
+		bnode = external_port_node_rel(b,b_base);
+		bdata = external_port_data_rel(b,b_base);
 	    } else {
 		a_tag = PORT_DEF;
 		goto mixed_types;
@@ -2321,9 +2336,9 @@ tailrecur_ne:
 	    if (is_internal_pid(b)) {
 		bnode = erts_this_node;
 		bdata = internal_pid_data(b);
-	    } else if (is_external_pid(b)) {
-		bnode = external_pid_node(b);
-		bdata = external_pid_data(b);
+	    } else if (is_external_pid_rel(b,b_base)) {
+		bnode = external_pid_node_rel(b,b_base);
+		bdata = external_pid_data_rel(b,b_base);
 	    } else {
 		a_tag = PID_DEF;
 		goto mixed_types;
@@ -2356,12 +2371,12 @@ tailrecur_ne:
 	    a_tag = LIST_DEF;
 	    goto mixed_types;
 	}
-	aa = list_val(a);
-	bb = list_val(b);
+	aa = list_val_rel(a,a_base);
+	bb = list_val_rel(b,b_base);
 	while (1) {
 	    Eterm atmp = CAR(aa);
 	    Eterm btmp = CAR(bb);
-	    if (atmp != btmp) {
+	    if (!is_same(atmp,a_base,btmp,b_base)) {
 		WSTACK_PUSH2(stack,(UWord) CDR(bb),(UWord) CDR(aa));
 		a = atmp;
 		b = btmp;
@@ -2369,7 +2384,7 @@ tailrecur_ne:
 	    }
 	    atmp = CDR(aa);
 	    btmp = CDR(bb);
-	    if (atmp == btmp) {
+	    if (is_same(atmp,a_base,btmp,b_base)) {
 		goto pop_next;
 	    }
 	    if (is_not_list(atmp) || is_not_list(btmp)) {
@@ -2377,20 +2392,20 @@ tailrecur_ne:
 		b = btmp;
 		goto tailrecur_ne;
 	    }
-	    aa = list_val(atmp);
-	    bb = list_val(btmp);
+	    aa = list_val_rel(atmp,a_base);
+	    bb = list_val_rel(btmp,b_base);
 	}
     case TAG_PRIMARY_BOXED:
 	{
-	    Eterm ahdr = *boxed_val(a);
+	    Eterm ahdr = *boxed_val_rel(a,a_base);
 	    switch ((ahdr & _TAG_HEADER_MASK) >> _TAG_PRIMARY_SIZE) {
 	    case (_TAG_HEADER_ARITYVAL >> _TAG_PRIMARY_SIZE):
-		if (is_not_tuple(b)) {
+		if (!is_tuple_rel(b,b_base)) {
 		    a_tag = TUPLE_DEF;
 		    goto mixed_types;
 		}
-		aa = tuple_val(a);
-		bb = tuple_val(b);
+		aa = tuple_val_rel(a,a_base);
+		bb = tuple_val_rel(b,b_base);
 		/* compare the arities */
 		i = arityval(ahdr);	/* get the arity*/
 		if (i != arityval(*bb)) {
@@ -2404,31 +2419,31 @@ tailrecur_ne:
 		goto term_array;
 
 	    case (_TAG_HEADER_FLOAT >> _TAG_PRIMARY_SIZE):
-		if (is_not_float(b)) {
+		if (!is_float_rel(b,b_base)) {
 		    a_tag = FLOAT_DEF;
 		    goto mixed_types;
 		} else {
 		    FloatDef af;
 		    FloatDef bf; 
 
-		    GET_DOUBLE(a, af);
-		    GET_DOUBLE(b, bf);
+		    GET_DOUBLE_REL(a, af, a_base);
+		    GET_DOUBLE_REL(b, bf, b_base);
 		    ON_CMP_GOTO(float_comp(af.fd, bf.fd));
 		}
 	    case (_TAG_HEADER_POS_BIG >> _TAG_PRIMARY_SIZE):
 	    case (_TAG_HEADER_NEG_BIG >> _TAG_PRIMARY_SIZE):
-		if (is_not_big(b)) {
+		if (!is_big_rel(b,b_base)) {
 		    a_tag = BIG_DEF;
 		    goto mixed_types;
 		}
-		ON_CMP_GOTO(big_comp(a, b));
+		ON_CMP_GOTO(big_comp(rterm2wterm(a,a_base), rterm2wterm(b,b_base)));
 	    case (_TAG_HEADER_EXPORT >> _TAG_PRIMARY_SIZE):
-		if (is_not_export(b)) {
+		if (!is_export_rel(b,b_base)) {
 		    a_tag = EXPORT_DEF;
 		    goto mixed_types;
 		} else {
-		    Export* a_exp = *((Export **) (export_val(a) + 1));
-		    Export* b_exp = *((Export **) (export_val(b) + 1));
+		    Export* a_exp = *((Export **) (export_val_rel(a,a_base) + 1));
+		    Export* b_exp = *((Export **) (export_val_rel(b,b_base) + 1));
 
 		    if ((j = cmp_atoms(a_exp->code[0], b_exp->code[0])) != 0) {
 			RETURN_NEQ(j);
@@ -2440,12 +2455,12 @@ tailrecur_ne:
 		}
 		break;
 	    case (_TAG_HEADER_FUN >> _TAG_PRIMARY_SIZE):
-		if (is_not_fun(b)) {
+		if (!is_fun_rel(b,b_base)) {
 		    a_tag = FUN_DEF;
 		    goto mixed_types;
 		} else {
-		    ErlFunThing* f1 = (ErlFunThing *) fun_val(a);
-		    ErlFunThing* f2 = (ErlFunThing *) fun_val(b);
+		    ErlFunThing* f1 = (ErlFunThing *) fun_val_rel(a,a_base);
+		    ErlFunThing* f2 = (ErlFunThing *) fun_val_rel(b,b_base);
 		    Sint diff;
 
 		    diff = cmpbytes(atom_tab(atom_val(f1->fe->module))->name,
@@ -2477,51 +2492,57 @@ tailrecur_ne:
 		if (is_internal_pid(b)) {
 		    bnode = erts_this_node;
 		    bdata = internal_pid_data(b);
-		} else if (is_external_pid(b)) {
-		    bnode = external_pid_node(b);
-		    bdata = external_pid_data(b);
+		} else if (is_external_pid_rel(b,b_base)) {
+		    bnode = external_pid_node_rel(b,b_base);
+		    bdata = external_pid_data_rel(b,b_base);
 		} else {
 		    a_tag = EXTERNAL_PID_DEF;
 		    goto mixed_types;
 		}
-		anode = external_pid_node(a);
-		adata = external_pid_data(a);
+		anode = external_pid_node_rel(a,a_base);
+		adata = external_pid_data_rel(a,a_base);
 		goto pid_common;
 	    case (_TAG_HEADER_EXTERNAL_PORT >> _TAG_PRIMARY_SIZE):
 		if (is_internal_port(b)) {
 		    bnode = erts_this_node;
 		    bdata = internal_port_data(b);
-		} else if (is_external_port(b)) {
-		    bnode = external_port_node(b);
-		    bdata = external_port_data(b);
+		} else if (is_external_port_rel(b,b_base)) {
+		    bnode = external_port_node_rel(b,b_base);
+		    bdata = external_port_data_rel(b,b_base);
 		} else {
 		    a_tag = EXTERNAL_PORT_DEF;
 		    goto mixed_types;
 		}
-		anode = external_port_node(a);
-		adata = external_port_data(a);
+		anode = external_port_node_rel(a,a_base);
+		adata = external_port_data_rel(a,a_base);
 		goto port_common;
 	    case (_TAG_HEADER_REF >> _TAG_PRIMARY_SIZE):
 		/*
 		 * Note! When comparing refs we need to compare ref numbers
 		 * (32-bit words), *not* ref data words.
 		 */
+
 		
-		if (is_internal_ref(b)) {
+		if (is_internal_ref_rel(b,b_base)) {
+		    RefThing* bthing = ref_thing_ptr_rel(b,b_base);
 		    bnode = erts_this_node;
-		    bnum = internal_ref_numbers(b);
-		    blen = internal_ref_no_of_numbers(b);
-		} else if(is_external_ref(b)) {
-		    bnode = external_ref_node(b);
-		    bnum = external_ref_numbers(b);
-		    blen = external_ref_no_of_numbers(b);
+		    bnum = internal_thing_ref_numbers(bthing);
+		    blen = internal_thing_ref_no_of_numbers(bthing);
+		} else if(is_external_ref_rel(b,b_base)) {
+		    ExternalThing* bthing = external_thing_ptr_rel(b,b_base);
+		    bnode = bthing->node;
+		    bnum = external_thing_ref_numbers(bthing);
+		    blen = external_thing_ref_no_of_numbers(bthing);
 		} else {
 		    a_tag = REF_DEF;
 		    goto mixed_types;
 		}
-		anode = erts_this_node;
-		anum = internal_ref_numbers(a);
-		alen = internal_ref_no_of_numbers(a);
+		{
+		    RefThing* athing = ref_thing_ptr_rel(a,a_base);
+		    anode = erts_this_node;
+		    anum = internal_thing_ref_numbers(athing);
+		    alen = internal_thing_ref_no_of_numbers(athing);
+		}
 		
 	    ref_common:
 		CMP_NODES(anode, bnode);
@@ -2550,31 +2571,36 @@ tailrecur_ne:
 			RETURN_NEQ((Sint32) (anum[i] - bnum[i]));
 		goto pop_next;
 	    case (_TAG_HEADER_EXTERNAL_REF >> _TAG_PRIMARY_SIZE):
-		if (is_internal_ref(b)) {
+		if (is_internal_ref_rel(b,b_base)) {
+		    RefThing* bthing = ref_thing_ptr_rel(b,b_base);
 		    bnode = erts_this_node;
-		    bnum = internal_ref_numbers(b);
-		    blen = internal_ref_no_of_numbers(b);
-		} else if (is_external_ref(b)) {
-		    bnode = external_ref_node(b);
-		    bnum = external_ref_numbers(b);
-		    blen = external_ref_no_of_numbers(b);
+		    bnum = internal_thing_ref_numbers(bthing);
+		    blen = internal_thing_ref_no_of_numbers(bthing);
+		} else if (is_external_ref_rel(b,b_base)) {
+		    ExternalThing* bthing = external_thing_ptr_rel(b,b_base);
+		    bnode = bthing->node;
+		    bnum = external_thing_ref_numbers(bthing);
+		    blen = external_thing_ref_no_of_numbers(bthing);
 		} else {
 		    a_tag = EXTERNAL_REF_DEF;
 		    goto mixed_types;
 		}
-		anode = external_ref_node(a);
-		anum = external_ref_numbers(a);
-		alen = external_ref_no_of_numbers(a);
+		{
+		    ExternalThing* athing = external_thing_ptr_rel(a,a_base);
+		    anode = athing->node;
+		    anum = external_thing_ref_numbers(athing);
+		    alen = external_thing_ref_no_of_numbers(athing);
+		}
 		goto ref_common;
 	    default:
 		/* Must be a binary */
-		ASSERT(is_binary(a));
-		if (is_not_binary(b)) {
+		ASSERT(is_binary_rel(a,a_base));
+		if (!is_binary_rel(b,b_base)) {
 		    a_tag = BINARY_DEF;
 		    goto mixed_types;
 		} else {
-		    Uint a_size = binary_size(a);
-		    Uint b_size = binary_size(b);
+		    Uint a_size = binary_size_rel(a,a_base);
+		    Uint b_size = binary_size_rel(b,b_base);
 		    Uint a_bitsize;
 		    Uint b_bitsize;
 		    Uint a_bitoffs;
@@ -2583,8 +2609,8 @@ tailrecur_ne:
 		    int cmp;
 		    byte* a_ptr;
 		    byte* b_ptr;
-		    ERTS_GET_BINARY_BYTES(a, a_ptr, a_bitoffs, a_bitsize);
-		    ERTS_GET_BINARY_BYTES(b, b_ptr, b_bitoffs, b_bitsize);
+		    ERTS_GET_BINARY_BYTES_REL(a, a_ptr, a_bitoffs, a_bitsize, a_base);
+		    ERTS_GET_BINARY_BYTES_REL(b, b_ptr, b_bitoffs, b_bitsize, b_base);
 		    if ((a_bitsize | b_bitsize | a_bitoffs | b_bitoffs) == 0) {
 			min_size = (a_size < b_size) ? a_size : b_size;
 			if ((cmp = sys_memcmp(a_ptr, b_ptr, min_size)) != 0) {
@@ -2611,7 +2637,6 @@ tailrecur_ne:
      */
 
  mixed_types:
-    b_tag = tag_val_def(b);
 
     {
 	FloatDef f1, f2;
@@ -2621,39 +2646,47 @@ tailrecur_ne:
 #else
 	Eterm *big_buf = erts_get_scheduler_data()->cmp_tmp_heap;
 #endif
+#if HALFWORD_HEAP
+	Wterm aw = is_immed(a) ? a : rterm2wterm(a,a_base);
+	Wterm bw = is_immed(b) ? b : rterm2wterm(b,b_base);
+#else
+	Eterm aw = a;
+	Eterm bw = b;
+#endif
+	b_tag = tag_val_def(bw);
 
 	switch(_NUMBER_CODE(a_tag, b_tag)) {
 	case SMALL_BIG:
 	    big = small_to_big(signed_val(a), big_buf);
-	    j = big_comp(big, b);
+	    j = big_comp(big, bw);
 	    break;
 	case SMALL_FLOAT:
 	    f1.fd = signed_val(a);
-	    GET_DOUBLE(b, f2);
+	    GET_DOUBLE(bw, f2);
 	    j = float_comp(f1.fd, f2.fd);
 	    break;
 	case BIG_SMALL:
 	    big = small_to_big(signed_val(b), big_buf);
-	    j = big_comp(a, big);
+	    j = big_comp(aw, big);
 	    break;
 	case BIG_FLOAT:
-	    if (big_to_double(a, &f1.fd) < 0) {
+	    if (big_to_double(aw, &f1.fd) < 0) {
 		j = big_sign(a) ? -1 : 1;
 	    } else {
-		GET_DOUBLE(b, f2);
+		GET_DOUBLE(bw, f2);
 		j = float_comp(f1.fd, f2.fd);
 	    }
 	    break;
 	case FLOAT_SMALL:
-	    GET_DOUBLE(a, f1);
+	    GET_DOUBLE(aw, f1);
 	    f2.fd = signed_val(b);
 	    j = float_comp(f1.fd, f2.fd);
 	    break;
 	case FLOAT_BIG:
-	    if (big_to_double(b, &f2.fd) < 0) {
+	    if (big_to_double(bw, &f2.fd) < 0) {
 		j = big_sign(b) ? 1 : -1;
 	    } else {
-		GET_DOUBLE(a, f1);
+		GET_DOUBLE(aw, f1);
 		j = float_comp(f1.fd, f2.fd);
 	    }
 	    break;