Merge tag 'OTP-19.0' into sverker/19/binary_to_atom-utf8-crash/ERL-474/OTP-14590

1 files changed, 1375 insertions, 597 deletions

diff --git a/erts/emulator/beam/external.c b/erts/emulator/beam/external.c
index 249b1e0923..beed847578 100644
--- a/erts/emulator/beam/external.c
+++ b/erts/emulator/beam/external.c
@@ -1,18 +1,19 @@
 /*
  * %CopyrightBegin%
  *
- * Copyright Ericsson AB 1996-2013. All Rights Reserved.
+ * Copyright Ericsson AB 1996-2016. 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
- * compliance with the License. You should have received a copy of the
- * Erlang Public License along with this software. If not, it can be
- * retrieved online at http://www.erlang.org/.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
  *
- * Software distributed under the License is distributed on an "AS IS"
- * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
- * the License for the specific language governing rights and limitations
- * under the License.
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
  *
  * %CopyrightEnd%
  */
@@ -36,21 +37,32 @@
 #include "erl_process.h"
 #include "error.h"
 #include "external.h"
+#define ERL_WANT_HIPE_BIF_WRAPPER__
 #include "bif.h"
+#undef ERL_WANT_HIPE_BIF_WRAPPER__
 #include "big.h"
 #include "dist.h"
 #include "erl_binary.h"
 #include "erl_bits.h"
 #include "erl_zlib.h"
+#include "erl_map.h"
 
-#ifdef HIPE
-#include "hipe_mode_switch.h"
-#endif
 #define in_area(ptr,start,nbytes) ((UWord)((char*)(ptr) - (char*)(start)) < (nbytes))
 
 #define MAX_STRING_LEN 0xffff
 
-#define is_valid_creation(Cre) ((unsigned)(Cre) < MAX_CREATION || (Cre) == INTERNAL_CREATION)
+/* MAX value for the creation field in pid, port and reference
+   for the local node and for the current external format.
+
+   Larger creation values than this are allowed in external pid, port and refs
+   encoded with NEW_PID_EXT, NEW_PORT_EXT and NEWER_REFERENCE_EXT.
+   The point here is to prepare for future upgrade to 32-bit creation.
+   OTP-19 (erts-8.0) can handle big creation values from other (newer) nodes,
+   but do not use big creation values for the local node yet,
+   as we still may have to communicate with older nodes.
+*/
+#define ERTS_MAX_LOCAL_CREATION (3)
+#define is_valid_creation(Cre) ((unsigned)(Cre) <= ERTS_MAX_LOCAL_CREATION)
 
 #undef ERTS_DEBUG_USE_DIST_SEP
 #ifdef DEBUG
@@ -61,6 +73,9 @@
  */
 #    define ERTS_DEBUG_USE_DIST_SEP
 #  endif
+#  define IF_DEBUG(X) X
+#else
+#  define IF_DEBUG(X)
 #endif
 
 /* Does Sint fit in Sint32?
@@ -84,38 +99,40 @@
 static Export term_to_binary_trap_export;
 
 static byte* enc_term(ErtsAtomCacheMap *, Eterm, byte*, Uint32, struct erl_off_heap_header** off_heap);
-static int enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags,
+struct TTBEncodeContext_;
+static int enc_term_int(struct TTBEncodeContext_*,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags,
 			struct erl_off_heap_header** off_heap, Sint *reds, byte **res);
 static Uint is_external_string(Eterm obj, int* p_is_string);
 static byte* enc_atom(ErtsAtomCacheMap *, Eterm, byte*, Uint32);
 static byte* enc_pid(ErtsAtomCacheMap *, Eterm, byte*, Uint32);
-static byte* dec_term(ErtsDistExternal *, Eterm**, byte*, ErlOffHeap*, Eterm*);
+struct B2TContext_t;
+static byte* dec_term(ErtsDistExternal*, ErtsHeapFactory*, byte*, Eterm*, struct B2TContext_t*);
 static byte* dec_atom(ErtsDistExternal *, byte*, Eterm*);
-static byte* dec_pid(ErtsDistExternal *, Eterm**, byte*, ErlOffHeap*, Eterm*);
-static Sint decoded_size(byte *ep, byte* endp, int internal_tags);
+static byte* dec_pid(ErtsDistExternal *, ErtsHeapFactory*, byte*, Eterm*, byte tag);
+static Sint decoded_size(byte *ep, byte* endp, int internal_tags, struct B2TContext_t*);
 static BIF_RETTYPE term_to_binary_trap_1(BIF_ALIST_1);
 
 static Eterm erts_term_to_binary_int(Process* p, Eterm Term, int level, Uint flags, 
 				     Binary *context_b);
 
 static Uint encode_size_struct2(ErtsAtomCacheMap *, Eterm, unsigned);
-static int encode_size_struct_int(Process *p, ErtsAtomCacheMap *acmp, Eterm obj, 
+struct TTBSizeContext_;
+static int encode_size_struct_int(struct TTBSizeContext_*, ErtsAtomCacheMap *acmp, Eterm obj,
 				  unsigned dflags, Sint *reds, Uint *res);
 
+static Export binary_to_term_trap_export;
+static BIF_RETTYPE binary_to_term_trap_1(BIF_ALIST_1);
+static BIF_RETTYPE binary_to_term_int(Process* p, Uint32 flags, Eterm bin, Binary* context_b,
+				      Export *bif, Eterm arg0, Eterm arg1);
+
 void erts_init_external(void) {
-#if 1 /* In R16 */
     erts_init_trap_export(&term_to_binary_trap_export,
-			  am_erlang, am_term_to_binary_trap, 1,
+			  am_erts_internal, am_term_to_binary_trap, 1,
 			  &term_to_binary_trap_1);
-#else
-    sys_memset((void *) &term_to_binary_trap_export, 0, sizeof(Export));
-    term_to_binary_trap_export.address = &term_to_binary_trap_export.code[3];
-    term_to_binary_trap_export.code[0] = am_erlang;
-    term_to_binary_trap_export.code[1] = am_term_to_binary_trap;
-    term_to_binary_trap_export.code[2] = 1;
-    term_to_binary_trap_export.code[3] = (BeamInstr) em_apply_bif;
-    term_to_binary_trap_export.code[4] = (BeamInstr) &term_to_binary_trap_1;
-#endif    
+
+    erts_init_trap_export(&binary_to_term_trap_export,
+			  am_erts_internal, am_binary_to_term_trap, 1,
+			  &binary_to_term_trap_1);
     return;
 }
 
@@ -495,15 +512,37 @@ byte *erts_encode_ext_dist_header_finalize(byte *ext, ErtsAtomCache *cache, Uint
     return ep;
 }
 
-Uint erts_encode_dist_ext_size(Eterm term, Uint32 flags, ErtsAtomCacheMap *acmp)
+int erts_encode_dist_ext_size(Eterm term, Uint32 flags, ErtsAtomCacheMap *acmp,
+			      Uint* szp)
 {
-    Uint sz = 0;
+    Uint sz;
+    if (encode_size_struct_int(NULL, acmp, term, flags, NULL, &sz)) {
+	return -1;
+    } else {
 #ifndef ERTS_DEBUG_USE_DIST_SEP
-    if (!(flags & DFLAG_DIST_HDR_ATOM_CACHE))
+	if (!(flags & DFLAG_DIST_HDR_ATOM_CACHE))
 #endif
-	sz++ /* VERSION_MAGIC */;
-    sz += encode_size_struct2(acmp, term, flags);
-    return sz;
+	    sz++ /* VERSION_MAGIC */;
+
+	*szp += sz;
+	return 0;
+    }
+}
+
+int erts_encode_dist_ext_size_int(Eterm term, struct erts_dsig_send_context* ctx, Uint* szp)
+{
+    Uint sz;
+    if (encode_size_struct_int(&ctx->u.sc, ctx->acmp, term, ctx->flags, &ctx->reds, &sz)) {
+	return -1;
+    } else {
+#ifndef ERTS_DEBUG_USE_DIST_SEP
+	if (!(ctx->flags & DFLAG_DIST_HDR_ATOM_CACHE))
+#endif
+	    sz++ /* VERSION_MAGIC */;
+
+	*szp += sz;
+	return 0;
+    }
 }
 
 Uint erts_encode_ext_size(Eterm term)
@@ -514,7 +553,7 @@ Uint erts_encode_ext_size(Eterm term)
 
 Uint erts_encode_ext_size_2(Eterm term, unsigned dflags)
 {
-    return encode_size_struct2(NULL, term, TERM_TO_BINARY_DFLAGS|dflags)
+    return encode_size_struct2(NULL, term, dflags)
         + 1 /* VERSION_MAGIC */;
 }
 
@@ -524,19 +563,16 @@ Uint erts_encode_ext_size_ets(Eterm term)
 }
 
 
-void erts_encode_dist_ext(Eterm term, byte **ext, Uint32 flags, ErtsAtomCacheMap *acmp)
+int erts_encode_dist_ext(Eterm term, byte **ext, Uint32 flags, ErtsAtomCacheMap *acmp,
+			  TTBEncodeContext* ctx, Sint* reds)
 {
-    byte *ep = *ext;
-#ifndef ERTS_DEBUG_USE_DIST_SEP
-    if (!(flags & DFLAG_DIST_HDR_ATOM_CACHE))
-#endif
-	*ep++ = VERSION_MAGIC;
-    ep = enc_term(acmp, term, ep, flags, NULL);
-    if (!ep)
-	erl_exit(ERTS_ABORT_EXIT,
-		 "%s:%d:erts_encode_dist_ext(): Internal data structure error\n",
-		 __FILE__, __LINE__);
-    *ext = ep;
+    if (!ctx || !ctx->wstack.wstart) {
+    #ifndef ERTS_DEBUG_USE_DIST_SEP
+	if (!(flags & DFLAG_DIST_HDR_ATOM_CACHE))
+    #endif
+	    *(*ext)++ = VERSION_MAGIC;
+    }
+    return enc_term_int(ctx, acmp, term, *ext, flags, NULL, reds, ext);
 }
 
 void erts_encode_ext(Eterm term, byte **ext)
@@ -545,7 +581,7 @@ void erts_encode_ext(Eterm term, byte **ext)
     *ep++ = VERSION_MAGIC;
     ep = enc_term(NULL, term, ep, TERM_TO_BINARY_DFLAGS, NULL);
     if (!ep)
-	erl_exit(ERTS_ABORT_EXIT,
+	erts_exit(ERTS_ABORT_EXIT,
 		 "%s:%d:erts_encode_ext(): Internal data structure error\n",
 		 __FILE__, __LINE__);
     *ext = ep;
@@ -877,7 +913,7 @@ erts_decode_dist_ext_size(ErtsDistExternal *edep)
 	    goto fail;
 	ep = edep->extp+1;
     }
-    res = decoded_size(ep, edep->ext_endp, 0);
+    res = decoded_size(ep, edep->ext_endp, 0, NULL);
     if (res >= 0)
 	return res;
  fail:
@@ -889,12 +925,12 @@ Sint erts_decode_ext_size(byte *ext, Uint size)
 {
     if (size == 0 || *ext != VERSION_MAGIC)
 	return -1;
-    return decoded_size(ext+1, ext+size, 0);
+    return decoded_size(ext+1, ext+size, 0, NULL);
 }
 
 Sint erts_decode_ext_size_ets(byte *ext, Uint size)
 {
-    Sint sz = decoded_size(ext, ext+size, 1);
+    Sint sz = decoded_size(ext, ext+size, 1, NULL);
     ASSERT(sz >= 0);
     return sz;
 }
@@ -906,8 +942,7 @@ Sint erts_decode_ext_size_ets(byte *ext, Uint size)
 ** on return hpp is updated to point after allocated data
 */
 Eterm
-erts_decode_dist_ext(Eterm** hpp,
-		     ErlOffHeap* off_heap,
+erts_decode_dist_ext(ErtsHeapFactory* factory,
 		     ErtsDistExternal *edep)
 {
     Eterm obj;
@@ -927,7 +962,7 @@ erts_decode_dist_ext(Eterm** hpp,
 	    goto error;
 	ep++;
     }
-    ep = dec_term(edep, hpp, ep, off_heap, &obj);
+    ep = dec_term(edep, factory, ep, &obj, NULL);
     if (!ep)
 	goto error;
 
@@ -936,33 +971,41 @@ erts_decode_dist_ext(Eterm** hpp,
     return obj;
 
  error:
+    erts_factory_undo(factory);
 
     bad_dist_ext(edep);
 
     return THE_NON_VALUE;
 }
 
-Eterm erts_decode_ext(Eterm **hpp, ErlOffHeap *off_heap, byte **ext)
+Eterm erts_decode_ext(ErtsHeapFactory* factory, byte **ext, Uint32 flags)
 {
+    ErtsDistExternal ede, *edep;
     Eterm obj;
     byte *ep = *ext;
-    if (*ep++ != VERSION_MAGIC)
+    if (*ep++ != VERSION_MAGIC) {
+        erts_factory_undo(factory);
 	return THE_NON_VALUE;
-    ep = dec_term(NULL, hpp, ep, off_heap, &obj);
+    }
+    if (flags) {
+        ASSERT(flags == ERTS_DIST_EXT_BTT_SAFE);
+        ede.flags = flags; /* a dummy struct just for the flags */
+        edep = &ede;
+    } else {
+        edep = NULL;
+    }
+    ep = dec_term(edep, factory, ep, &obj, NULL);
     if (!ep) {
-#ifdef DEBUG
-	bin_write(ERTS_PRINT_STDERR,NULL,*ext,500);
-#endif
 	return THE_NON_VALUE;
     }
     *ext = ep;
     return obj;
 }
 
-Eterm erts_decode_ext_ets(Eterm **hpp, ErlOffHeap *off_heap, byte *ext)
+Eterm erts_decode_ext_ets(ErtsHeapFactory* factory, byte *ext)
 {
     Eterm obj;
-    ext = dec_term(NULL, hpp, ext, off_heap, &obj);
+    ext = dec_term(NULL, factory, ext, &obj, NULL);
     ASSERT(ext);
     return obj;
 }
@@ -971,9 +1014,8 @@ Eterm erts_decode_ext_ets(Eterm **hpp, ErlOffHeap *off_heap, byte *ext)
 
 BIF_RETTYPE erts_debug_dist_ext_to_term_2(BIF_ALIST_2)
 {
+    ErtsHeapFactory factory;
     Eterm res;
-    Eterm *hp;
-    Eterm *hendp;
     Sint hsz;
     ErtsDistExternal ede;
     Eterm *tp;
@@ -1020,12 +1062,9 @@ BIF_RETTYPE erts_debug_dist_ext_to_term_2(BIF_ALIST_2)
     if (hsz < 0)
 	goto badarg;
 
-    hp = HAlloc(BIF_P, (Uint) hsz);
-    hendp = hp + hsz;
-
-    res = erts_decode_dist_ext(&hp, &MSO(BIF_P), &ede);
-
-    HRelease(BIF_P, hendp, hp);
+    erts_factory_proc_prealloc_init(&factory, BIF_P, hsz);
+    res = erts_decode_dist_ext(&factory, &ede);
+    erts_factory_close(&factory);
 
     if (is_value(res))
 	BIF_RET(res);
@@ -1043,22 +1082,33 @@ static BIF_RETTYPE term_to_binary_trap_1(BIF_ALIST_1)
     Binary *bin = ((ProcBin *) binary_val(bt))->val;
     Eterm res = erts_term_to_binary_int(BIF_P, Term, 0, 0,bin);
     if (is_tuple(res)) {
+	ASSERT(BIF_P->flags & F_DISABLE_GC);
 	BIF_TRAP1(&term_to_binary_trap_export,BIF_P,res);
     } else {
-	BIF_RET(res);
+        if (erts_set_gc_state(BIF_P, 1)
+            || MSO(BIF_P).overhead > BIN_VHEAP_SZ(BIF_P))
+            ERTS_BIF_YIELD_RETURN(BIF_P, res);
+        else
+            BIF_RET(res);
     }
 }
-    
+
+HIPE_WRAPPER_BIF_DISABLE_GC(term_to_binary, 1)
+
 BIF_RETTYPE term_to_binary_1(BIF_ALIST_1)
 {
     Eterm res = erts_term_to_binary_int(BIF_P, BIF_ARG_1, 0, TERM_TO_BINARY_DFLAGS, NULL);
     if (is_tuple(res)) {
+	erts_set_gc_state(BIF_P, 0);
 	BIF_TRAP1(&term_to_binary_trap_export,BIF_P,res);
     } else {
+	ASSERT(!(BIF_P->flags & F_DISABLE_GC));
 	BIF_RET(res);
     }
 }
 
+HIPE_WRAPPER_BIF_DISABLE_GC(term_to_binary, 2)
+
 BIF_RETTYPE term_to_binary_2(BIF_ALIST_2)
 {
     Process* p = BIF_P;
@@ -1067,7 +1117,6 @@ BIF_RETTYPE term_to_binary_2(BIF_ALIST_2)
     int level = 0;
     Uint flags = TERM_TO_BINARY_DFLAGS;
     Eterm res;
-    Binary *bin = NULL;
 
     while (is_list(Flags)) {
 	Eterm arg = CAR(list_val(Flags));
@@ -1078,10 +1127,10 @@ BIF_RETTYPE term_to_binary_2(BIF_ALIST_2)
 	    if (tp[1] == am_minor_version && is_small(tp[2])) {
 		switch (signed_val(tp[2])) {
 		case 0:
-		    flags = TERM_TO_BINARY_DFLAGS;
+		    flags = TERM_TO_BINARY_DFLAGS & ~DFLAG_NEW_FLOATS;
 		    break;
 		case 1:
-		    flags = TERM_TO_BINARY_DFLAGS|DFLAG_NEW_FLOATS;
+		    flags = TERM_TO_BINARY_DFLAGS;
 		    break;
 		default:
 		    goto error;
@@ -1104,14 +1153,76 @@ BIF_RETTYPE term_to_binary_2(BIF_ALIST_2)
 	goto error;
     }
 
-    res = erts_term_to_binary_int(p, Term, level, flags, bin);
+    res = erts_term_to_binary_int(p, Term, level, flags, NULL);
     if (is_tuple(res)) {
+	erts_set_gc_state(p, 0);
 	BIF_TRAP1(&term_to_binary_trap_export,BIF_P,res);
     } else {
+	ASSERT(!(BIF_P->flags & F_DISABLE_GC));
 	BIF_RET(res);
     }
 }
 
+
+enum B2TState { /* order is somewhat significant */
+    B2TPrepare,
+    B2TUncompressChunk,
+    B2TSizeInit,
+    B2TSize,
+    B2TDecodeInit,
+    B2TDecode,
+    B2TDecodeList,
+    B2TDecodeTuple,
+    B2TDecodeString,
+    B2TDecodeBinary,
+
+    B2TDone,
+    B2TDecodeFail,
+    B2TBadArg
+};
+
+typedef struct {
+    int heap_size;
+    int terms;
+    byte* ep;
+    int atom_extra_skip;
+} B2TSizeContext;
+
+typedef struct {
+    byte*  ep;
+    Eterm  res;
+    Eterm* next;
+    ErtsHeapFactory factory;
+    int remaining_n;
+    char* remaining_bytes;
+    ErtsWStack flat_maps;
+    ErtsPStack hamt_array;
+} B2TDecodeContext;
+
+typedef struct {
+    z_stream stream;
+    byte* dbytes;
+    Uint dleft;
+} B2TUncompressContext;
+
+typedef struct B2TContext_t {
+    Sint heap_size;
+    byte* aligned_alloc;
+    ErtsBinary2TermState b2ts;
+    Uint32 flags;
+    SWord reds;
+    Eterm trap_bin;
+    Export *bif;
+    Eterm arg[2];
+    enum B2TState state;
+    union {
+	B2TSizeContext sc;
+	B2TDecodeContext dc;
+	B2TUncompressContext uc;
+    } u;
+} B2TContext;
+
+
 static uLongf binary2term_uncomp_size(byte* data, Sint size)
 {
     z_stream stream;
@@ -1141,48 +1252,62 @@ static uLongf binary2term_uncomp_size(byte* data, Sint size)
     return err == Z_STREAM_END ? uncomp_size : 0;
 }
 
-static ERTS_INLINE Sint
-binary2term_prepare(ErtsBinary2TermState *state, byte *data, Sint data_size)
+static ERTS_INLINE int
+binary2term_prepare(ErtsBinary2TermState *state, byte *data, Sint data_size,
+		    B2TContext* ctx)
 {
-    Sint res;
     byte *bytes = data;
     Sint size = data_size;
 
     state->exttmp = 0;
 
     if (size < 1 || *bytes != VERSION_MAGIC) {
-    error:
-	if (state->exttmp)
-	    erts_free(ERTS_ALC_T_TMP, state->extp);
-	state->extp = NULL;
-	state->exttmp = 0;
 	return -1;
     }
     bytes++;
     size--;
     if (size < 5 || *bytes != COMPRESSED) {
 	state->extp = bytes;
+        if (ctx)
+	    ctx->state = B2TSizeInit;
     }
     else  {
 	uLongf dest_len = (Uint32) get_int32(bytes+1);
 	bytes += 5;
 	size -= 5;	
 	if (dest_len > 32*1024*1024
-	    || (state->extp = erts_alloc_fnf(ERTS_ALC_T_TMP, dest_len)) == NULL) {
+	    || (state->extp = erts_alloc_fnf(ERTS_ALC_T_EXT_TERM_DATA, dest_len)) == NULL) {
+            /*
+             * Try avoid out-of-memory crash due to corrupted 'dest_len'
+             * by checking the actual length of the uncompressed data.
+             * The only way to do that is to uncompress it. Sad but true.
+             */
 	    if (dest_len != binary2term_uncomp_size(bytes, size)) {
-		goto error;
+                return -1;
 	    }
-	    state->extp = erts_alloc(ERTS_ALC_T_TMP, dest_len);
+	    state->extp = erts_alloc(ERTS_ALC_T_EXT_TERM_DATA, dest_len);
+            ctx->reds -= dest_len;
 	}
 	state->exttmp = 1;
-	if (erl_zlib_uncompress(state->extp, &dest_len, bytes, size) != Z_OK)
-	    goto error;
+        if (ctx) {
+	    if (erl_zlib_inflate_start(&ctx->u.uc.stream, bytes, size) != Z_OK)
+		return -1;
+
+	    ctx->u.uc.dbytes = state->extp;
+	    ctx->u.uc.dleft = dest_len;
+	    ctx->state = B2TUncompressChunk;
+        }
+	else {
+	    uLongf dlen = dest_len;
+	    if (erl_zlib_uncompress(state->extp, &dlen, bytes, size) != Z_OK
+		|| dlen != dest_len) {
+		return -1;
+	    }
+        }
 	size = (Sint) dest_len;
     }
-    res = decoded_size(state->extp, state->extp + size, 0);
-    if (res < 0)
-	goto error;
-    return res;
+    state->extsize = size;
+    return 0;
 }
 
 static ERTS_INLINE void
@@ -1190,19 +1315,21 @@ binary2term_abort(ErtsBinary2TermState *state)
 {
     if (state->exttmp) {
 	state->exttmp = 0;
-	erts_free(ERTS_ALC_T_TMP, state->extp);
+	erts_free(ERTS_ALC_T_EXT_TERM_DATA, state->extp);
     }
 }
 
 static ERTS_INLINE Eterm
-binary2term_create(ErtsDistExternal *edep, ErtsBinary2TermState *state, Eterm **hpp, ErlOffHeap *ohp)
+binary2term_create(ErtsDistExternal *edep, ErtsBinary2TermState *state,
+		   ErtsHeapFactory* factory)
 {
     Eterm res;
-    if (!dec_term(edep, hpp, state->extp, ohp, &res))
+
+    if (!dec_term(edep, factory, state->extp, &res, NULL))
 	res = THE_NON_VALUE;
     if (state->exttmp) {
 	state->exttmp = 0;
-	erts_free(ERTS_ALC_T_TMP, state->extp);
+	erts_free(ERTS_ALC_T_EXT_TERM_DATA, state->extp);
     }
     return res;
 }
@@ -1210,7 +1337,18 @@ binary2term_create(ErtsDistExternal *edep, ErtsBinary2TermState *state, Eterm **
 Sint
 erts_binary2term_prepare(ErtsBinary2TermState *state, byte *data, Sint data_size)
 {
-    return binary2term_prepare(state, data, data_size);
+    Sint res;
+
+    if (binary2term_prepare(state, data, data_size, NULL) < 0 ||
+        (res=decoded_size(state->extp, state->extp + state->extsize, 0, NULL)) < 0) {
+
+        if (state->exttmp)
+            erts_free(ERTS_ALC_T_EXT_TERM_DATA, state->extp);
+        state->extp = NULL;
+	state->exttmp = 0;
+	return -1;
+    }
+    return res;
 }
 
 void
@@ -1220,73 +1358,278 @@ erts_binary2term_abort(ErtsBinary2TermState *state)
 }
 
 Eterm
-erts_binary2term_create(ErtsBinary2TermState *state, Eterm **hpp, ErlOffHeap *ohp)
+erts_binary2term_create(ErtsBinary2TermState *state, ErtsHeapFactory* factory)
 {
-    return binary2term_create(NULL,state, hpp, ohp);
+    return binary2term_create(NULL,state, factory);
 }
 
-BIF_RETTYPE binary_to_term_1(BIF_ALIST_1)
+static void b2t_destroy_context(B2TContext* context)
 {
-    Sint heap_size;
-    Eterm res;
+    erts_free_aligned_binary_bytes_extra(context->aligned_alloc,
+                                         ERTS_ALC_T_EXT_TERM_DATA);
+    context->aligned_alloc = NULL;
+    binary2term_abort(&context->b2ts);
+    switch (context->state) {
+    case B2TUncompressChunk:
+	erl_zlib_inflate_finish(&context->u.uc.stream);
+	break;
+    case B2TDecode:
+    case B2TDecodeList:
+    case B2TDecodeTuple:
+    case B2TDecodeString:
+    case B2TDecodeBinary:
+	if (context->u.dc.hamt_array.pstart) {
+	    erts_free(context->u.dc.hamt_array.alloc_type,
+		      context->u.dc.hamt_array.pstart);
+	}
+	break;
+    default:;
+    }
+}
+
+static void b2t_context_destructor(Binary *context_bin)
+{
+    B2TContext* ctx = (B2TContext*) ERTS_MAGIC_BIN_DATA(context_bin);
+    ASSERT(ERTS_MAGIC_BIN_DESTRUCTOR(context_bin) == b2t_context_destructor);
+
+    b2t_destroy_context(ctx);
+}
+
+static BIF_RETTYPE binary_to_term_trap_1(BIF_ALIST_1)
+{
+    Binary *context_bin = ((ProcBin *) binary_val(BIF_ARG_1))->val;
+    ASSERT(ERTS_MAGIC_BIN_DESTRUCTOR(context_bin) == b2t_context_destructor);
+
+    return binary_to_term_int(BIF_P, 0, THE_NON_VALUE, context_bin, NULL,
+			      THE_NON_VALUE, THE_NON_VALUE);
+}
+
+
+#define B2T_BYTES_PER_REDUCTION 128
+#define B2T_MEMCPY_FACTOR 8
+
+/* Define for testing */
+/*#define EXTREME_B2T_TRAPPING 1*/
+
+#ifdef EXTREME_B2T_TRAPPING
+static unsigned b2t_rand(void)
+{
+    static unsigned prev = 17;
+    prev = (prev * 214013 + 2531011);
+    return prev;
+}
+#endif
+
+
+static B2TContext* b2t_export_context(Process* p, B2TContext* src)
+{
+    Binary* context_b = erts_create_magic_binary(sizeof(B2TContext),
+                                                 b2t_context_destructor);
+    B2TContext* ctx = ERTS_MAGIC_BIN_DATA(context_b);
     Eterm* hp;
-    Eterm* endp;
-    Sint size;
-    byte* bytes;
-    byte* temp_alloc = NULL;
-    ErtsBinary2TermState b2ts;
+    sys_memcpy(ctx, src, sizeof(B2TContext));
+    if (ctx->state >= B2TDecode && ctx->u.dc.next == &src->u.dc.res) {
+        ctx->u.dc.next = &ctx->u.dc.res;
+    }
+    hp = HAlloc(p, PROC_BIN_SIZE);
+    ctx->trap_bin = erts_mk_magic_binary_term(&hp, &MSO(p), context_b);
+    return ctx;
+}
 
-    if ((bytes = erts_get_aligned_binary_bytes(BIF_ARG_1, &temp_alloc)) == NULL) {
-    error:
-	erts_free_aligned_binary_bytes(temp_alloc);
-	BIF_ERROR(BIF_P, BADARG);
+static BIF_RETTYPE binary_to_term_int(Process* p, Uint32 flags, Eterm bin, Binary* context_b,
+				      Export *bif_init, Eterm arg0, Eterm arg1)
+{
+    BIF_RETTYPE ret_val;
+#ifdef EXTREME_B2T_TRAPPING
+    SWord initial_reds = 1 + b2t_rand() % 4;
+#else
+    SWord initial_reds = (Uint)(ERTS_BIF_REDS_LEFT(p) * B2T_BYTES_PER_REDUCTION);
+#endif
+    B2TContext c_buff;
+    B2TContext *ctx;
+    int is_first_call;
+
+    if (context_b == NULL) {
+	/* Setup enough to get started */
+        is_first_call = 1;
+        ctx = &c_buff;
+	ctx->state = B2TPrepare;
+        ctx->aligned_alloc = NULL;
+        ctx->flags = flags;
+	ctx->bif = bif_init;
+	ctx->arg[0] = arg0;
+	ctx->arg[1] = arg1;
+        IF_DEBUG(ctx->trap_bin = THE_NON_VALUE;)
+    } else {
+        is_first_call = 0;
+	ctx = ERTS_MAGIC_BIN_DATA(context_b);
+        ASSERT(ctx->state != B2TPrepare);
     }
-    size = binary_size(BIF_ARG_1);
+    ctx->reds = initial_reds;
+
+    do {
+        switch (ctx->state) {
+        case B2TPrepare: {
+	    byte* bytes;
+            Uint bin_size;
+            bytes = erts_get_aligned_binary_bytes_extra(bin,
+                                                        &ctx->aligned_alloc,
+                                                        ERTS_ALC_T_EXT_TERM_DATA,
+                                                        0);
+            if (bytes == NULL) {
+                ctx->b2ts.exttmp = 0;
+                ctx->state = B2TBadArg;
+                break;
+            }
+            bin_size = binary_size(bin);
+            if (ctx->aligned_alloc) {
+                ctx->reds -= bin_size / 8;
+            }
+            if (binary2term_prepare(&ctx->b2ts, bytes, bin_size, ctx) < 0) {
+		ctx->state = B2TBadArg;
+	    }
+            break;
+        }
+	case B2TUncompressChunk: {
+            uLongf chunk = ctx->reds;
+            int zret;
+
+            if (chunk > ctx->u.uc.dleft)
+                chunk = ctx->u.uc.dleft;
+            zret = erl_zlib_inflate_chunk(&ctx->u.uc.stream,
+                                          ctx->u.uc.dbytes, &chunk);
+            ctx->u.uc.dbytes += chunk;
+            ctx->u.uc.dleft  -= chunk;
+            if (zret == Z_OK && ctx->u.uc.dleft > 0) {
+                ctx->reds = 0;
+            }
+            else if (erl_zlib_inflate_finish(&ctx->u.uc.stream) == Z_OK
+                     && zret == Z_STREAM_END
+                     && ctx->u.uc.dleft == 0) {
+                ctx->reds -= chunk;
+                ctx->state = B2TSizeInit;
+            }
+            else {
+                ctx->state = B2TBadArg;
+            }
+            break;
+        }
+	case B2TSizeInit:
+	    ctx->u.sc.ep = NULL;
+	    ctx->state = B2TSize;
+	    /*fall through*/
+        case B2TSize:
+            ctx->heap_size = decoded_size(ctx->b2ts.extp,
+					  ctx->b2ts.extp + ctx->b2ts.extsize,
+                                          0, ctx);
+            break;
+
+        case B2TDecodeInit:
+            if (ctx == &c_buff && ctx->b2ts.extsize > ctx->reds) {
+                /* dec_term will maybe trap, allocate space for magic bin
+                   before result term to make it easy to trim with HRelease.
+                 */
+                ctx = b2t_export_context(p, &c_buff);
+            }
+            ctx->u.dc.ep = ctx->b2ts.extp;
+            ctx->u.dc.res = (Eterm) (UWord) NULL;
+            ctx->u.dc.next = &ctx->u.dc.res;
+	    erts_factory_proc_prealloc_init(&ctx->u.dc.factory, p, ctx->heap_size);
+	    ctx->u.dc.flat_maps.wstart = NULL;
+	    ctx->u.dc.hamt_array.pstart = NULL;
+            ctx->state = B2TDecode;
+            /*fall through*/
+	case B2TDecode:
+        case B2TDecodeList:
+        case B2TDecodeTuple:
+        case B2TDecodeString:
+        case B2TDecodeBinary: {
+	    ErtsDistExternal fakedep;
+            fakedep.flags = ctx->flags;
+            dec_term(&fakedep, NULL, NULL, NULL, ctx);
+            break;
+	}
+        case B2TDecodeFail:
+            /*fall through*/
+        case B2TBadArg:
+            BUMP_REDS(p, (initial_reds - ctx->reds) / B2T_BYTES_PER_REDUCTION);
 
-    heap_size = binary2term_prepare(&b2ts, bytes, size);
-    if (heap_size < 0)
-	goto error;
+	    ASSERT(ctx->bif == bif_export[BIF_binary_to_term_1]
+		   || ctx->bif == bif_export[BIF_binary_to_term_2]);
+
+	    if (is_first_call)
+		ERTS_BIF_PREP_ERROR(ret_val, p, BADARG);
+	    else {
+                erts_set_gc_state(p, 1);
+		if (is_non_value(ctx->arg[1]))
+		    ERTS_BIF_PREP_ERROR_TRAPPED1(ret_val, p, BADARG, ctx->bif,
+						 ctx->arg[0]);
+		else
+		    ERTS_BIF_PREP_ERROR_TRAPPED2(ret_val, p, BADARG, ctx->bif,
+						 ctx->arg[0], ctx->arg[1]);
+	    }
+            b2t_destroy_context(ctx);
+	    return ret_val;
 
-    hp = HAlloc(BIF_P, heap_size);
-    endp = hp + heap_size;
+        case B2TDone:
+            b2t_destroy_context(ctx);
 
-    res = binary2term_create(NULL, &b2ts, &hp, &MSO(BIF_P));
+            if (ctx->u.dc.factory.hp > ctx->u.dc.factory.hp_end) {
+                erts_exit(ERTS_ERROR_EXIT, ":%s, line %d: heap overrun by %d words(s)\n",
+                         __FILE__, __LINE__, ctx->u.dc.factory.hp - ctx->u.dc.factory.hp_end);
+            }
+	    erts_factory_close(&ctx->u.dc.factory);
 
-    erts_free_aligned_binary_bytes(temp_alloc);
+            if (!is_first_call) {
+                erts_set_gc_state(p, 1);
+            }
+            BUMP_REDS(p, (initial_reds - ctx->reds) / B2T_BYTES_PER_REDUCTION);
+	    ERTS_BIF_PREP_RET(ret_val, ctx->u.dc.res);
+	    return ret_val;
 
-    if (hp > endp) {
-	erl_exit(1, ":%s, line %d: heap overrun by %d words(s)\n",
-		 __FILE__, __LINE__, hp-endp);
+        default:
+            ASSERT(!"Unknown state in binary_to_term");
+        }
+    }while (ctx->reds > 0 || ctx->state >= B2TDone);
+
+    if (ctx == &c_buff) {
+        ASSERT(ctx->trap_bin == THE_NON_VALUE);
+        ctx = b2t_export_context(p, &c_buff);
     }
+    ASSERT(ctx->trap_bin != THE_NON_VALUE);
 
-    HRelease(BIF_P, endp, hp);
+    if (is_first_call) {
+        erts_set_gc_state(p, 0);
+    }
+    BUMP_ALL_REDS(p);
 
-    if (res == THE_NON_VALUE)
-	goto error;
+    ERTS_BIF_PREP_TRAP1(ret_val, &binary_to_term_trap_export,
+			p, ctx->trap_bin);
 
-    return res;
+    return ret_val;
+}
+
+HIPE_WRAPPER_BIF_DISABLE_GC(binary_to_term, 1)
+
+BIF_RETTYPE binary_to_term_1(BIF_ALIST_1)
+{
+    return binary_to_term_int(BIF_P, 0, BIF_ARG_1, NULL, bif_export[BIF_binary_to_term_1],
+			      BIF_ARG_1, THE_NON_VALUE);
 }
 
+HIPE_WRAPPER_BIF_DISABLE_GC(binary_to_term, 2)
+
 BIF_RETTYPE binary_to_term_2(BIF_ALIST_2)
 {
-    Sint heap_size;
-    Eterm res;
     Eterm opts;
     Eterm opt;
-    Eterm* hp;
-    Eterm* endp;
-    Sint size;
-    byte* bytes;
-    byte* temp_alloc = NULL;
-    ErtsBinary2TermState b2ts;
-    ErtsDistExternal fakedep;
+    Uint32 flags = 0;
 
-    fakedep.flags = 0;
     opts = BIF_ARG_2;
     while (is_list(opts)) {
         opt = CAR(list_val(opts));
         if (opt == am_safe) {
-	    fakedep.flags |= ERTS_DIST_EXT_BTT_SAFE;
+            flags |= ERTS_DIST_EXT_BTT_SAFE;
         }
 	else {
             goto error;
@@ -1297,35 +1640,11 @@ BIF_RETTYPE binary_to_term_2(BIF_ALIST_2)
     if (is_not_nil(opts))
         goto error;
 
-    if ((bytes = erts_get_aligned_binary_bytes(BIF_ARG_1, &temp_alloc)) == NULL) {
-    error:
-	erts_free_aligned_binary_bytes(temp_alloc);
-	BIF_ERROR(BIF_P, BADARG);
-    }
-    size = binary_size(BIF_ARG_1);
-
-    heap_size = binary2term_prepare(&b2ts, bytes, size);
-    if (heap_size < 0)
-	goto error;
-
-    hp = HAlloc(BIF_P, heap_size);
-    endp = hp + heap_size;
-
-    res = binary2term_create(&fakedep, &b2ts, &hp, &MSO(BIF_P));
-
-    erts_free_aligned_binary_bytes(temp_alloc);
-
-    if (hp > endp) {
-	erl_exit(1, ":%s, line %d: heap overrun by %d words(s)\n",
-		 __FILE__, __LINE__, hp-endp);
-    }
-
-    HRelease(BIF_P, endp, hp);
-
-    if (res == THE_NON_VALUE)
-	goto error;
+    return binary_to_term_int(BIF_P, flags, BIF_ARG_1, NULL, bif_export[BIF_binary_to_term_2],
+			      BIF_ARG_1, BIF_ARG_2);
 
-    return res;
+error:
+    BIF_ERROR(BIF_P, BADARG);
 }
 
 Eterm
@@ -1357,9 +1676,9 @@ external_size_2(BIF_ALIST_2)
             if (tp[1] == am_minor_version && is_small(tp[2])) {
                 switch (signed_val(tp[2])) {
                 case 0:
+                    flags &= ~DFLAG_NEW_FLOATS;
                     break;
                 case 1:
-                    flags |= DFLAG_NEW_FLOATS;
                     break;
                 default:
                     goto error;
@@ -1405,12 +1724,12 @@ erts_term_to_binary_simple(Process* p, Eterm Term, Uint size, int level, Uint fl
 
 	if ((endp = enc_term(NULL, Term, bytes, flags, NULL))
 	    == NULL) {
-	    erl_exit(1, "%s, line %d: bad term: %x\n",
+	    erts_exit(ERTS_ERROR_EXIT, "%s, line %d: bad term: %x\n",
 		     __FILE__, __LINE__, Term);
 	}
 	real_size = endp - bytes;
 	if (real_size > size) {
-	    erl_exit(1, "%s, line %d: buffer overflow: %d word(s)\n",
+	    erts_exit(ERTS_ERROR_EXIT, "%s, line %d: buffer overflow: %d word(s)\n",
 		     __FILE__, __LINE__, real_size - size);
 	}
 
@@ -1450,12 +1769,12 @@ erts_term_to_binary_simple(Process* p, Eterm Term, Uint size, int level, Uint fl
 	bytes[0] = VERSION_MAGIC;
 	if ((endp = enc_term(NULL, Term, bytes+1, flags, NULL))
 	    == NULL) {
-	    erl_exit(1, "%s, line %d: bad term: %x\n",
+	    erts_exit(ERTS_ERROR_EXIT, "%s, line %d: bad term: %x\n",
 		     __FILE__, __LINE__, Term);
 	}
 	real_size = endp - bytes;
 	if (real_size > size) {
-	    erl_exit(1, "%s, line %d: buffer overflow: %d word(s)\n",
+	    erts_exit(ERTS_ERROR_EXIT, "%s, line %d: buffer overflow: %d word(s)\n",
 		     __FILE__, __LINE__, endp - (bytes + size));
 	}
 	return erts_realloc_binary(bin, real_size);
@@ -1469,60 +1788,26 @@ erts_term_to_binary(Process* p, Eterm Term, int level, Uint flags) {
     return erts_term_to_binary_simple(p, Term, size, level, flags);
 }
 
-/* Define for testing */
-/* #define EXTREME_TTB_TRAPPING 1 */
+/* Define EXTREME_TTB_TRAPPING for testing in dist.h */
 
 #ifndef EXTREME_TTB_TRAPPING
-#define TERM_TO_BINARY_LOOP_FACTOR 500
-#define TERM_TO_BINARY_SIZE_FACTOR 500000
-#define TERM_TO_BINARY_COMPRESS_CHUNK 500000
+#define TERM_TO_BINARY_COMPRESS_CHUNK (1 << 18)
 #else
-#define TERM_TO_BINARY_LOOP_FACTOR 1
-#define TERM_TO_BINARY_SIZE_FACTOR 10
 #define TERM_TO_BINARY_COMPRESS_CHUNK 10
 #endif
+#define TERM_TO_BINARY_MEMCPY_FACTOR 8
 
-
-typedef enum { TTBSize, TTBEncode, TTBCompress } TTBState;
-typedef struct {
-    Uint flags;
-    int level;
-} TTBSizeContext;
-
-typedef struct {
-    Uint flags;
-    int level;
-    Binary *result_bin;
-} TTBEncodeContext;
-
-typedef struct {
-    Uint real_size;
-    Uint dest_len;
-    byte *dbytes;
-    Binary *result_bin;
-    Binary *destination_bin;
-    z_stream stream;
-} TTBCompressContext;
-
-typedef struct {
-    int alive;
-    TTBState state;
-    union {
-	TTBSizeContext sc;
-	TTBEncodeContext ec;
-	TTBCompressContext cc;
-    } s;
-} TTBContext;
-
-static void context_destructor(Binary *context_bin) 
+static void ttb_context_destructor(Binary *context_bin)
 {
     TTBContext *context = ERTS_MAGIC_BIN_DATA(context_bin);
     if (context->alive) {
 	context->alive = 0;
 	switch (context->state) {
 	case TTBSize:
+	    DESTROY_SAVED_WSTACK(&context->s.sc.wstack);
 	    break;
 	case TTBEncode:
+	    DESTROY_SAVED_WSTACK(&context->s.ec.wstack);
 	    if (context->s.ec.result_bin != NULL) { /* Set to NULL if ever made alive! */
 		ASSERT(erts_refc_read(&(context->s.ec.result_bin->refc),0) == 0);
 		erts_bin_free(context->s.ec.result_bin);
@@ -1567,7 +1852,7 @@ static Eterm erts_term_to_binary_int(Process* p, Eterm Term, int level, Uint fla
     do {								\
 	if (context_b == NULL) {					\
 	    context_b = erts_create_magic_binary(sizeof(TTBContext),    \
-                                                 context_destructor);   \
+                                                 ttb_context_destructor);   \
 	    context =  ERTS_MAGIC_BIN_DATA(context_b);			\
 	    memcpy(context,&c_buff,sizeof(TTBContext));			\
 	}								\
@@ -1587,6 +1872,7 @@ static Eterm erts_term_to_binary_int(Process* p, Eterm Term, int level, Uint fla
 	/* Setup enough to get started */
 	context->state = TTBSize;
 	context->alive = 1;
+	context->s.sc.wstack.wstart = NULL;
 	context->s.sc.flags = flags;
 	context->s.sc.level = level;
     } else {
@@ -1602,7 +1888,8 @@ static Eterm erts_term_to_binary_int(Process* p, Eterm Term, int level, Uint fla
 		int level;
 		Uint flags;
 		/* Try for fast path */
-		if (encode_size_struct_int(p, NULL, Term, context->s.sc.flags, &reds, &size) < 0) {
+		if (encode_size_struct_int(&context->s.sc, NULL, Term,
+					   context->s.sc.flags, &reds, &size) < 0) {
 		    EXPORT_CONTEXT();
 		    /* Same state */
 		    RETURN_STATE();
@@ -1615,19 +1902,18 @@ static Eterm erts_term_to_binary_int(Process* p, Eterm Term, int level, Uint fla
 		    /* Finish in one go */
 		    res = erts_term_to_binary_simple(p, Term, size, 
 						     level, flags);
-		    BUMP_REDS(p, size / TERM_TO_BINARY_SIZE_FACTOR);
+		    BUMP_REDS(p, 1);
 		    return res;
 		}
 
 		result_bin = erts_bin_nrml_alloc(size);
-		result_bin->flags = 0;
-		result_bin->orig_size = size;
 		erts_refc_init(&result_bin->refc, 0);
 		result_bin->orig_bytes[0] = VERSION_MAGIC;
 		/* Next state immediately, no need to export context */
 		context->state = TTBEncode;
 		context->s.ec.flags = flags;
 		context->s.ec.level = level;
+		context->s.ec.wstack.wstart = NULL;
 		context->s.ec.result_bin = result_bin;
 		break;
 	    }
@@ -1639,7 +1925,7 @@ static Eterm erts_term_to_binary_int(Process* p, Eterm Term, int level, Uint fla
 		Binary *result_bin;
 
 		flags = context->s.ec.flags;
-		if (enc_term_int(p,NULL,Term, bytes+1, flags, NULL, &reds, &endp) < 0) {
+		if (enc_term_int(&context->s.ec, NULL,Term, bytes+1, flags, NULL, &reds, &endp) < 0) {
 		    EXPORT_CONTEXT();
 		    RETURN_STATE();
 		}
@@ -1681,8 +1967,6 @@ static Eterm erts_term_to_binary_int(Process* p, Eterm Term, int level, Uint fla
 		context->s.cc.result_bin = result_bin;
 
 		result_bin = erts_bin_nrml_alloc(real_size);
-		result_bin->flags = 0;
-		result_bin->orig_size = real_size;
 		erts_refc_init(&result_bin->refc, 0);
 		result_bin->orig_bytes[0] = VERSION_MAGIC;
 
@@ -1875,16 +2159,28 @@ enc_atom(ErtsAtomCacheMap *acmp, Eterm atom, byte *ep, Uint32 dflags)
     return ep;
 }
 
+/*
+ * We use this atom as sysname in local pid/port/refs
+ * for the ETS compressed format (DFLAG_INTERNAL_TAGS).
+ *
+ * We used atom '' earlier but that turned out to cause problems
+ * for buggy erl_interface/ic usage of c-nodes with empty node names.
+ * A long atom reduces risk of nodes actually called this and the length
+ * does not matter anyway as it's encoded with atom index (ATOM_INTERNAL_REF2).
+ */
+#define INTERNAL_LOCAL_SYSNAME am_await_microstate_accounting_modifications
+
 static byte*
 enc_pid(ErtsAtomCacheMap *acmp, Eterm pid, byte* ep, Uint32 dflags)
 {
     Uint on, os;
+    Eterm sysname = ((is_internal_pid(pid) && (dflags & DFLAG_INTERNAL_TAGS))
+		      ? INTERNAL_LOCAL_SYSNAME : pid_node_name(pid));
+    Uint32 creation = pid_creation(pid);
+    byte* tagp = ep++;
 
-    *ep++ = PID_EXT;
     /* insert  atom here containing host and sysname  */
-    ep = enc_atom(acmp, pid_node_name(pid), ep, dflags);
-
-    /* two bytes for each number and serial */
+    ep = enc_atom(acmp, sysname, ep, dflags);
 
     on = pid_number(pid);
     os = pid_serial(pid);
@@ -1893,8 +2189,15 @@ enc_pid(ErtsAtomCacheMap *acmp, Eterm pid, byte* ep, Uint32 dflags)
     ep += 4;
     put_int32(os, ep);
     ep += 4;
-    *ep++ = (is_internal_pid(pid) && (dflags & DFLAG_INTERNAL_TAGS)) ?
-	INTERNAL_CREATION : pid_creation(pid);
+    if (creation <= ERTS_MAX_LOCAL_CREATION) {
+        *tagp = PID_EXT;
+        *ep++ = creation;
+    } else {
+        ASSERT(is_external_pid(pid));
+        *tagp = NEW_PID_EXT;
+        put_int32(creation, ep);
+        ep += 4;
+    }
     return ep;
 }
 
@@ -1974,27 +2277,27 @@ dec_atom(ErtsDistExternal *edep, byte* ep, Eterm* objp)
     return ep;
 }
 
-static ERTS_INLINE ErlNode* dec_get_node(Eterm sysname, Uint creation)
+static ERTS_INLINE ErlNode* dec_get_node(Eterm sysname, Uint32 creation)
 {
-    switch (creation) {
-    case INTERNAL_CREATION:
+    if (sysname == INTERNAL_LOCAL_SYSNAME)  /* && DFLAG_INTERNAL_TAGS */
 	return erts_this_node;
-    case ORIG_CREATION:
-	if (sysname == erts_this_node->sysname) {
-	    creation = erts_this_node->creation;
-	}
-    }
+
+    if (sysname == erts_this_node->sysname
+	&& (creation == erts_this_node->creation || creation == ORIG_CREATION))
+	return erts_this_node;
+
     return erts_find_or_insert_node(sysname,creation);
 }
 
 static byte*
-dec_pid(ErtsDistExternal *edep, Eterm** hpp, byte* ep, ErlOffHeap* off_heap, Eterm* objp)
+dec_pid(ErtsDistExternal *edep, ErtsHeapFactory* factory, byte* ep,
+        Eterm* objp, byte tag)
 {
     Eterm sysname;
     Uint data;
     Uint num;
     Uint ser;
-    Uint cre;
+    Uint32 cre;
     ErlNode *node;
 
     *objp = NIL;		/* In case we fail, don't leave a hole in the heap */
@@ -2010,12 +2313,19 @@ dec_pid(ErtsDistExternal *edep, Eterm** hpp, byte* ep, ErlOffHeap* off_heap, Ete
     ep += 4;
     if (ser > ERTS_MAX_PID_SERIAL)
 	return NULL;
-    cre = get_int8(ep);
-    ep += 1;
 
-    if (!is_valid_creation(cre)) {
-	return NULL;
+    if (tag == PID_EXT) {
+        cre = get_int8(ep);
+        ep += 1;
+        if (!is_valid_creation(cre)) {
+            return NULL;
+        }
+    } else {
+        ASSERT(tag == NEW_PID_EXT);
+        cre = get_int32(ep);
+        ep += 4;
     }
+
     data = make_pid_data(ser, num);
 
     /*
@@ -2027,15 +2337,15 @@ dec_pid(ErtsDistExternal *edep, Eterm** hpp, byte* ep, ErlOffHeap* off_heap, Ete
     if(node == erts_this_node) {
 	*objp = make_internal_pid(data);
     } else {
-	ExternalThing *etp = (ExternalThing *) *hpp;
-	*hpp += EXTERNAL_THING_HEAD_SIZE + 1;
+	ExternalThing *etp = (ExternalThing *) factory->hp;
+	factory->hp += EXTERNAL_THING_HEAD_SIZE + 1;
 
 	etp->header = make_external_pid_header(1);
-	etp->next = off_heap->first;
+	etp->next = factory->off_heap->first;
 	etp->node = node;
 	etp->data.ui[0] = data;
 
-	off_heap->first = (struct erl_off_heap_header*) etp;
+	factory->off_heap->first = (struct erl_off_heap_header*) etp;
 	*objp = make_external_pid(etp);
     }
     return ep;
@@ -2045,29 +2355,10 @@ dec_pid(ErtsDistExternal *edep, Eterm** hpp, byte* ep, ErlOffHeap* off_heap, Ete
 #define ENC_TERM ((Eterm) 0)
 #define ENC_ONE_CONS ((Eterm) 1)
 #define ENC_PATCH_FUN_SIZE ((Eterm) 2)
-#define ENC_LAST_ARRAY_ELEMENT ((Eterm) 3)
-
-/* Free extra rootset (used when trapping) */
-static void cleanup_ttb_extra_root(ErlExtraRootSet *rs)
-{
-    if (rs->objv != NULL) {
-	erts_free(ERTS_ALC_T_EXTRA_ROOT, rs->objv);
-    }
-    erts_free(ERTS_ALC_T_EXTRA_ROOT, rs);
-}
-
-/* Same as above, but we have an extra "stack" beyond GC reach, i.e. an array of two extra roots */
-static void cleanup_ttb_extra_root_2(ErlExtraRootSet *rs)
-{
-    if (rs->objv != NULL) {
-	erts_free(ERTS_ALC_T_EXTRA_ROOT, rs->objv);
-    }
-    if (rs[1].objv != NULL) {
-	erts_free(ERTS_ALC_T_EXTRA_ROOT, rs[1].objv);
-    }
-	
-    erts_free(ERTS_ALC_T_EXTRA_ROOT, rs);
-}
+#define ENC_BIN_COPY ((Eterm) 3)
+#define ENC_MAP_PAIR ((Eterm) 4)
+#define ENC_HASHMAP_NODE ((Eterm) 5)
+#define ENC_LAST_ARRAY_ELEMENT ((Eterm) 6)
 
 static byte*
 enc_term(ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags,
@@ -2079,39 +2370,39 @@ enc_term(ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags,
 }
 
 static int
-enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags,
+enc_term_int(TTBEncodeContext* ctx, ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dflags,
 	     struct erl_off_heap_header** off_heap, Sint *reds, byte **res)
 {
-    DECLARE_ESTACK(s);
-    DECLARE_WSTACK(com);
+    DECLARE_WSTACK(s);
     Uint n;
     Uint i;
     Uint j;
     Uint* ptr;
     Eterm val;
     FloatDef f;
-    int count_reds = (p != NULL && reds != NULL);
     Sint r = 0;
 
-    if (count_reds) {
-	ESTACK_CHANGE_ALLOCATOR(s, ERTS_ALC_T_EXTRA_ROOT);
-	WSTACK_CHANGE_ALLOCATOR(com, ERTS_ALC_T_EXTRA_ROOT);
+    if (ctx) {
+	WSTACK_CHANGE_ALLOCATOR(s, ERTS_ALC_T_SAVED_ESTACK);
 	r = *reds;
-    }
 
-    if (p && p->extra_root) { /* restore saved stacks and byte pointer */
-	ESTACK_RESTORE(s,p->extra_root[0].objv, p->extra_root[0].sz);
-	obj = ESTACK_POP(s);
-	WSTACK_RESTORE(com, p->extra_root[1].objv, p->extra_root[1].sz);
-	ep = (byte *) WSTACK_POP(com);
+	if (ctx->wstack.wstart) { /* restore saved stacks and byte pointer */
+	    WSTACK_RESTORE(s, &ctx->wstack);
+	    ep = ctx->ep;
+	    obj = ctx->obj;
+	    if (is_non_value(obj)) {
+		goto outer_loop;
+	    }
+	}
     }
 
     goto L_jump_start;
 
  outer_loop:
-    while (!ESTACK_ISEMPTY(s)) {
-	obj = ESTACK_POP(s);
-	switch (val = WSTACK_POP(com)) {
+    while (!WSTACK_ISEMPTY(s)) {
+	obj = WSTACK_POP(s);
+
+	switch (val = WSTACK_POP(s)) {
 	case ENC_TERM:
 	    break;
 	case ENC_ONE_CONS:
@@ -2122,55 +2413,79 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla
 
 		obj = CAR(cons);
 		tl = CDR(cons);
-		WSTACK_PUSH(com, is_list(tl) ? ENC_ONE_CONS : ENC_TERM);
-		ESTACK_PUSH(s, tl);
+		WSTACK_PUSH2(s, (is_list(tl) ? ENC_ONE_CONS : ENC_TERM),
+			     tl);
 	    }
 	    break;
 	case ENC_PATCH_FUN_SIZE:
-	    /* obj will be discarded, it was NIL */
 	    {
-		byte* size_p = (byte *) WSTACK_POP(com);
+		byte* size_p = (byte *) obj;
 		put_int32(ep - size_p, size_p);
 	    }
 	    goto outer_loop;
+	case ENC_BIN_COPY: {
+	    Uint bits = (Uint)obj;
+	    Uint bitoffs = WSTACK_POP(s);
+	    byte* bytes = (byte*) WSTACK_POP(s);
+	    byte* dst = (byte*) WSTACK_POP(s);
+	    if (bits > r * (TERM_TO_BINARY_MEMCPY_FACTOR * 8)) {
+		Uint n = r * TERM_TO_BINARY_MEMCPY_FACTOR;
+		WSTACK_PUSH5(s, (UWord)(dst + n), (UWord)(bytes + n), bitoffs,
+			     ENC_BIN_COPY, bits - 8*n);
+		bits = 8*n;
+		copy_binary_to_buffer(dst, 0, bytes, bitoffs, bits);
+		obj = THE_NON_VALUE;
+		r = 0; /* yield */
+		break;
+	    } else {
+		copy_binary_to_buffer(dst, 0, bytes, bitoffs, bits);
+		r -= bits / (TERM_TO_BINARY_MEMCPY_FACTOR * 8);
+		goto outer_loop;
+	    }
+	}
+	case ENC_MAP_PAIR: {
+	    Uint pairs_left = obj;
+	    Eterm *vptr = (Eterm*) WSTACK_POP(s);
+	    Eterm *kptr = (Eterm*) WSTACK_POP(s);
+
+	    obj = *kptr;
+	    if (--pairs_left > 0) {
+		WSTACK_PUSH4(s, (UWord)(kptr+1), (UWord)(vptr+1),
+			     ENC_MAP_PAIR, pairs_left);
+	    }
+	    WSTACK_PUSH2(s, ENC_TERM, *vptr);
+	    break;
+	}
+	case ENC_HASHMAP_NODE:
+	    if (is_list(obj)) { /* leaf node [K|V] */
+		ptr = list_val(obj);
+		WSTACK_PUSH2(s, ENC_TERM, CDR(ptr));
+		obj = CAR(ptr);
+	    }
+	    break;
 	case ENC_LAST_ARRAY_ELEMENT:
 	    /* obj is the tuple */
 	    {
-		Eterm* ptr = tuple_val(obj);
-		i = arityval(*ptr);
-		obj = ptr[i];
+		Eterm* ptr = (Eterm *) obj;
+		obj = *ptr;
 	    }
 	    break;
 	default:		/* ENC_LAST_ARRAY_ELEMENT+1 and upwards */
 	    {
-		Eterm* ptr = tuple_val(obj);
-		i = arityval(*ptr);
-		ESTACK_PUSH(s, obj); /* put back tuple and next element index */
-		WSTACK_PUSH(com, val-1);
-		obj = ptr[i - (val - ENC_LAST_ARRAY_ELEMENT)]; /* the index is counting down */
+		Eterm* ptr = (Eterm *) obj;
+		obj = *ptr++;
+		WSTACK_PUSH2(s, val-1, (UWord)ptr);
 	    }
 	    break;
 	}
 
     L_jump_start:
 
-	if (count_reds && --r == 0) {
-	    *reds = r;
-	    ESTACK_PUSH(s,obj); /* push back current object, to be popped on restore */
-	    WSTACK_PUSH(com,((UWord) ep));
-	    if (p->extra_root == NULL) {
-		/* NB. Allocate an array of two "extra-roots", of which only the first element
-		   is seen and handled by the GC. Index 1 holds the Wstack. */
-		p->extra_root = erts_alloc(ERTS_ALC_T_EXTRA_ROOT, sizeof(ErlExtraRootSet)*2);
-		p->extra_root->objv = NULL;
-		p->extra_root->sz = 0;
-		p->extra_root->cleanup = cleanup_ttb_extra_root_2;
-		p->extra_root[1].objv = NULL;
-		p->extra_root[1].sz = 0;
-		p->extra_root[1].cleanup = NULL; /* Never used */
-	    }
-	    ESTACK_SAVE(s, p->extra_root[0].objv, p->extra_root[0].sz);
-	    WSTACK_SAVE(com, p->extra_root[1].objv, (p->extra_root[1].sz));
+	if (ctx && --r <= 0) {
+	    *reds = 0;
+	    ctx->obj = obj;
+	    ctx->ep = ep;
+	    WSTACK_SAVE(s, &ctx->wstack);
 	    return -1;
 	}
 	switch(tag_val_def(obj)) {
@@ -2250,16 +2565,26 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla
 	case REF_DEF:
 	case EXTERNAL_REF_DEF: {
 	    Uint32 *ref_num;
+	    Eterm sysname = (((dflags & DFLAG_INTERNAL_TAGS) && is_internal_ref(obj))
+			     ? INTERNAL_LOCAL_SYSNAME : ref_node_name(obj));
+            Uint32 creation = ref_creation(obj);
+            byte* tagp = ep++;
 
 	    ASSERT(dflags & DFLAG_EXTENDED_REFERENCES);
 
-	    *ep++ = NEW_REFERENCE_EXT;
 	    i = ref_no_of_numbers(obj);
 	    put_int16(i, ep);
 	    ep += 2;
-	    ep = enc_atom(acmp,ref_node_name(obj),ep,dflags);
-	    *ep++ = ((dflags & DFLAG_INTERNAL_TAGS) && is_internal_ref(obj)) ?
-		INTERNAL_CREATION : ref_creation(obj);
+	    ep = enc_atom(acmp, sysname, ep, dflags);
+            if (creation <= ERTS_MAX_LOCAL_CREATION) {
+                *tagp = NEW_REFERENCE_EXT;
+                *ep++ = creation;
+            } else {
+                ASSERT(is_external_ref(obj));
+                *tagp = NEWER_REFERENCE_EXT;
+                put_int32(creation, ep);
+                ep += 4;
+            }
 	    ref_num = ref_numbers(obj);
 	    for (j = 0; j < i; j++) {
 		put_int32(ref_num[j], ep);
@@ -2268,17 +2593,27 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla
 	    break;
 	}
 	case PORT_DEF:
-	case EXTERNAL_PORT_DEF:
+	case EXTERNAL_PORT_DEF: {
+	    Eterm sysname = (((dflags & DFLAG_INTERNAL_TAGS) && is_internal_port(obj))
+			     ? INTERNAL_LOCAL_SYSNAME : port_node_name(obj));
+            Uint32 creation = port_creation(obj);
+            byte* tagp = ep++;
 
-	    *ep++ = PORT_EXT;
-	    ep = enc_atom(acmp,port_node_name(obj),ep,dflags);
+	    ep = enc_atom(acmp, sysname, ep, dflags);
 	    j = port_number(obj);
 	    put_int32(j, ep);
 	    ep += 4;
-	    *ep++ = ((dflags & DFLAG_INTERNAL_TAGS) && is_internal_port(obj)) ?
-		INTERNAL_CREATION : port_creation(obj);
+            if (creation <= ERTS_MAX_LOCAL_CREATION) {
+                *tagp = PORT_EXT;
+                *ep++ = creation;
+            } else {
+                ASSERT(is_external_port(obj));
+                *tagp = NEW_PORT_EXT;
+                put_int32(creation, ep);
+                ep += 4;
+            }
 	    break;
-
+	}
 	case LIST_DEF:
 	    {
 		int is_str;
@@ -2316,16 +2651,64 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla
 		ep += 4;
 	    }
 	    if (i > 0) {
-		WSTACK_PUSH(com, ENC_LAST_ARRAY_ELEMENT+i-1);
-		ESTACK_PUSH(s, obj);
+		WSTACK_PUSH2(s, ENC_LAST_ARRAY_ELEMENT+i-1, (UWord)ptr);
 	    }
 	    break;
 
+	case MAP_DEF:
+	    if (is_flatmap(obj)) {
+		flatmap_t *mp = (flatmap_t*)flatmap_val(obj);
+		Uint size = flatmap_get_size(mp);
+
+		*ep++ = MAP_EXT;
+		put_int32(size, ep); ep += 4;
+
+		if (size > 0) {
+		    Eterm *kptr = flatmap_get_keys(mp);
+		    Eterm *vptr = flatmap_get_values(mp);
+
+		    WSTACK_PUSH4(s, (UWord)kptr, (UWord)vptr,
+				 ENC_MAP_PAIR, size);
+		}
+	    } else {
+		Eterm hdr;
+		Uint node_sz;
+		ptr = boxed_val(obj);
+		hdr = *ptr;
+		ASSERT(is_header(hdr));
+		switch(hdr & _HEADER_MAP_SUBTAG_MASK) {
+		case HAMT_SUBTAG_HEAD_ARRAY:
+		    *ep++ = MAP_EXT;
+		    ptr++;
+		    put_int32(*ptr, ep); ep += 4;
+		    node_sz = 16;
+		    break;
+		case HAMT_SUBTAG_HEAD_BITMAP:
+		    *ep++ = MAP_EXT;
+		    ptr++;
+		    put_int32(*ptr, ep); ep += 4;
+		    /*fall through*/
+		case HAMT_SUBTAG_NODE_BITMAP:
+		    node_sz = hashmap_bitcount(MAP_HEADER_VAL(hdr));
+		    ASSERT(node_sz < 17);
+		    break;
+		default:
+		    erts_exit(ERTS_ERROR_EXIT, "bad header\r\n");
+		}
+
+		ptr++;
+		WSTACK_RESERVE(s, node_sz*2);
+		while(node_sz--) {
+		    WSTACK_FAST_PUSH(s, ENC_HASHMAP_NODE);
+		    WSTACK_FAST_PUSH(s, *ptr++);
+		}
+	    }
+	    break;
 	case FLOAT_DEF:
 	    GET_DOUBLE(obj, f);
 	    if (dflags & DFLAG_NEW_FLOATS) {
 		*ep++ = NEW_FLOAT_EXT;
-#ifdef WORDS_BIGENDIAN
+#if defined(WORDS_BIGENDIAN) || defined(DOUBLE_MIDDLE_ENDIAN)
 		put_int32(f.fw[0], ep);
 		ep += 4;
 		put_int32(f.fw[1], ep);
@@ -2354,6 +2737,7 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla
 		Uint bitoffs;
 		Uint bitsize;
 		byte* bytes;
+		byte* data_dst;
 
 		ERTS_GET_BINARY_BYTES(obj, bytes, bitoffs, bitsize);
 		if (dflags & DFLAG_INTERNAL_TAGS) {
@@ -2399,7 +2783,7 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla
 		    j = binary_size(obj);
 		    put_int32(j, ep);
 		    ep += 4;
-		    copy_binary_to_buffer(ep, 0, bytes, bitoffs, 8*j);
+		    data_dst = ep;
 		    ep += j;
 		} else if (dflags & DFLAG_BIT_BINARIES) {
 		    /* Bit-level binary. */
@@ -2409,7 +2793,7 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla
 		    ep += 4;
 		    *ep++ = bitsize;
 		    ep[j] = 0;	/* Zero unused bits at end of binary */
-		    copy_binary_to_buffer(ep, 0, bytes, bitoffs, 8*j+bitsize);
+		    data_dst = ep;
 		    ep += j + 1;
 		} else {
 		    /*
@@ -2423,11 +2807,18 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla
 		    put_int32((j+1), ep);
 		    ep += 4;
 		    ep[j] = 0;	/* Zero unused bits at end of binary */
-		    copy_binary_to_buffer(ep, 0, bytes, bitoffs, 8*j+bitsize);
+		    data_dst = ep;
 		    ep += j+1;
 		    *ep++ = SMALL_INTEGER_EXT;
 		    *ep++ = bitsize;
 		}
+		if (ctx && j > r * TERM_TO_BINARY_MEMCPY_FACTOR) {
+		    WSTACK_PUSH5(s, (UWord)data_dst, (UWord)bytes, bitoffs,
+				 ENC_BIN_COPY, 8*j + bitsize);
+		} else {
+		    copy_binary_to_buffer(data_dst, 0, bytes, bitoffs,
+					  8 * j + bitsize);
+		}
 	    }
 	    break;
 	case EXPORT_DEF:
@@ -2456,14 +2847,12 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla
 	case FUN_DEF:
 	    {
 		ErlFunThing* funp = (ErlFunThing *) fun_val(obj);
+		int ei;
 
 		if ((dflags & DFLAG_NEW_FUN_TAGS) != 0) {
-		    int ei;
-
 		    *ep++ = NEW_FUN_EXT;
-		    WSTACK_PUSH(com, (UWord) ep); /* Position for patching in size */
-		    WSTACK_PUSH(com, ENC_PATCH_FUN_SIZE);
-		    ESTACK_PUSH(s,NIL); /* Will be thrown away */
+		    WSTACK_PUSH2(s, ENC_PATCH_FUN_SIZE,
+				 (UWord) ep); /* Position for patching in size */
 		    ep += 4;
 		    *ep = funp->arity;
 		    ep += 1;
@@ -2477,16 +2866,6 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla
 		    ep = enc_term(acmp, make_small(funp->fe->old_index), ep, dflags, off_heap);
 		    ep = enc_term(acmp, make_small(funp->fe->old_uniq), ep, dflags, off_heap);
 		    ep = enc_pid(acmp, funp->creator, ep, dflags);
-
-		fun_env:
-		    for (ei = funp->num_free-1; ei > 0; ei--) {
-			WSTACK_PUSH(com, ENC_TERM);
-			ESTACK_PUSH(s, (UWord) funp->env[ei]);
-		    }
-		    if (funp->num_free != 0) {
-			obj = funp->env[0];
-			goto L_jump_start;
-		    }
 		} else {
 		    /*
 		     * Communicating with an obsolete erl_interface or
@@ -2518,19 +2897,21 @@ enc_term_int(Process *p,ErtsAtomCacheMap *acmp, Eterm obj, byte* ep, Uint32 dfla
 		    *ep++ = SMALL_TUPLE_EXT;
 		    put_int8(funp->num_free, ep);
 		    ep += 1;
-		    goto fun_env;
+		}
+		for (ei = funp->num_free-1; ei > 0; ei--) {
+		    WSTACK_PUSH2(s, ENC_TERM, (UWord) funp->env[ei]);
+		}
+		if (funp->num_free != 0) {
+		    obj = funp->env[0];
+		    goto L_jump_start;
 		}
 	    }
 	    break;
 	}
     }
-    DESTROY_ESTACK(s);
-    DESTROY_WSTACK(com);
-    if (p && p->extra_root) {
-	cleanup_ttb_extra_root_2(p->extra_root);
-	p->extra_root = NULL;
-    }
-    if (count_reds) {
+    DESTROY_WSTACK(s);
+    if (ctx) {
+	ASSERT(ctx->wstack.wstart == NULL);
 	*reds = r;
     }
     *res = ep;
@@ -2576,51 +2957,136 @@ is_external_string(Eterm list, int* p_is_string)
     return len;
 }
 
-/* Assumes that the ones to undo are preluding the list. */ 
-static void
-undo_offheap_in_area(ErlOffHeap* off_heap, Eterm* start, Eterm* end)
-{
-    const Uint area_sz = (end - start) * sizeof(Eterm);
-    struct erl_off_heap_header* hdr;
-    struct erl_off_heap_header** hdr_nextp = NULL;
 
-    for (hdr = off_heap->first; ; hdr=hdr->next) {
-	if (!in_area(hdr, start, area_sz)) {
-	    if (hdr_nextp != NULL) {
-		*hdr_nextp = NULL;
-		erts_cleanup_offheap(off_heap);
-		off_heap->first = hdr;
-	    }
-	    break;
-	}
-	hdr_nextp = &hdr->next;
-    }    
+struct dec_term_hamt
+{
+    Eterm* objp; /* write result here */
+    Uint size;   /* nr of leafs */
+    Eterm* leaf_array;
+};
 
-    /* Assert that the ones to undo were indeed preluding the list. */ 
-#ifdef DEBUG
-    for (hdr = off_heap->first; hdr != NULL; hdr = hdr->next) {
-	ASSERT(!in_area(hdr, start, area_sz));
-    }    
-#endif /* DEBUG */
-}
 
 /* Decode term from external format into *objp.
-** On failure return NULL and (R13B04) *hpp will be unchanged.
+** On failure calls erts_factory_undo() and returns NULL
 */
 static byte*
-dec_term(ErtsDistExternal *edep, Eterm** hpp, byte* ep, ErlOffHeap* off_heap, Eterm* objp)
+dec_term(ErtsDistExternal *edep,
+	 ErtsHeapFactory* factory,
+	 byte* ep,
+         Eterm* objp,
+	 B2TContext* ctx)
 {
-    Eterm* hp_saved = *hpp;
+#define PSTACK_TYPE struct dec_term_hamt
+    PSTACK_DECLARE(hamt_array, 5);
     int n;
     ErtsAtomEncoding char_enc;
-    register Eterm* hp = *hpp;	/* Please don't take the address of hp */
-    Eterm* next = objp;
+    register Eterm* hp;        /* Please don't take the address of hp */
+    DECLARE_WSTACK(flat_maps); /* for preprocessing of small maps */
+    Eterm* next;
+    SWord reds;
+#ifdef DEBUG
+    Eterm* dbg_resultp = ctx ? &ctx->u.dc.res : objp;
+#endif
+
+    if (ctx) {
+        reds     = ctx->reds;
+        next     = ctx->u.dc.next;
+        ep       = ctx->u.dc.ep;
+	factory  = &ctx->u.dc.factory;
 
-    *next = (Eterm) (UWord) NULL;
+        if (ctx->state != B2TDecode) {
+            int n_limit = reds;
+
+	    n = ctx->u.dc.remaining_n;
+            if (ctx->state == B2TDecodeBinary) {
+                n_limit *= B2T_MEMCPY_FACTOR;
+                ASSERT(n_limit >= reds);
+		reds -= n / B2T_MEMCPY_FACTOR;
+            }
+	    else
+		reds -= n;
+
+            if (n > n_limit) {
+                ctx->u.dc.remaining_n -= n_limit;
+                n = n_limit;
+                reds = 0;
+            }
+            else {
+                ctx->u.dc.remaining_n = 0;
+            }
+
+            switch (ctx->state) {
+            case B2TDecodeList:
+                objp = next - 2;
+                while (n > 0) {
+                    objp[0] = (Eterm) next;
+                    objp[1] = make_list(next);
+                    next = objp;
+                    objp -= 2;
+                    n--;
+                }
+                break;
+
+            case B2TDecodeTuple:
+                objp = next - 1;
+                while (n-- > 0) {
+                    objp[0] = (Eterm) next;
+                    next = objp;
+                    objp--;
+                }
+                break;
+
+            case B2TDecodeString:
+                hp = factory->hp;
+                hp[-1] = make_list(hp);  /* overwrite the premature NIL */
+                while (n-- > 0) {
+                    hp[0] = make_small(*ep++);
+                    hp[1] = make_list(hp+2);
+                    hp += 2;
+                }
+                hp[-1] = NIL;
+		factory->hp = hp;
+                break;
+
+            case B2TDecodeBinary:
+                sys_memcpy(ctx->u.dc.remaining_bytes, ep, n);
+                ctx->u.dc.remaining_bytes += n;
+                ep += n;
+                break;
+
+            default:
+                ASSERT(!"Unknown state");
+            }
+            if (!ctx->u.dc.remaining_n) {
+                ctx->state = B2TDecode;
+            }
+            if (reds <= 0) {
+                ctx->u.dc.next = next;
+                ctx->u.dc.ep = ep;
+                ctx->reds = 0;
+                return NULL;
+            }
+        }
+	PSTACK_CHANGE_ALLOCATOR(hamt_array, ERTS_ALC_T_SAVED_ESTACK);
+        WSTACK_CHANGE_ALLOCATOR(flat_maps, ERTS_ALC_T_SAVED_ESTACK);
+	if (ctx->u.dc.hamt_array.pstart) {
+	    PSTACK_RESTORE(hamt_array, &ctx->u.dc.hamt_array);
+	}
+	if (ctx->u.dc.flat_maps.wstart) {
+	    WSTACK_RESTORE(flat_maps, &ctx->u.dc.flat_maps);
+	}
+    }
+    else {
+        reds = ERTS_SWORD_MAX;
+        next = objp;
+        *next = (Eterm) (UWord) NULL;
+    }
+    hp = factory->hp;
 
     while (next != NULL) {
+
 	objp = next;
-	next = (Eterm *) EXPAND_POINTER(*objp);
+	next = (Eterm *) *objp;
 
 	switch (*ep++) {
 	case INTEGER_EXT:
@@ -2628,7 +3094,7 @@ dec_term(ErtsDistExternal *edep, Eterm** hpp, byte* ep, ErlOffHeap* off_heap, Et
 		Sint sn = get_int32(ep);
 
 		ep += 4;
-#if defined(ARCH_64) && !HALFWORD_HEAP
+#if defined(ARCH_64)
 		*objp = make_small(sn);
 #else
 		if (MY_IS_SSMALL(sn)) {
@@ -2677,6 +3143,8 @@ dec_term(ErtsDistExternal *edep, Eterm** hpp, byte* ep, ErlOffHeap* off_heap, Et
 		    big = make_small(0);
 		} else {
 		    big = bytes_to_big(first, n, neg, hp);
+		    if (is_nil(big))
+			goto error;
 		    if (is_big(big)) {
 			hp += big_arity(big) + 1;
 		    }
@@ -2738,9 +3206,18 @@ dec_term_atom_common:
 	    *objp = make_tuple(hp);
 	    *hp++ = make_arityval(n);
 	    hp += n;
-	    objp = hp - 1;
+            objp = hp - 1;
+            if (ctx) {
+                if (reds < n) {
+                    ASSERT(reds > 0);
+                    ctx->state = B2TDecodeTuple;
+                    ctx->u.dc.remaining_n = n - reds;
+                    n = reds;
+                }
+		reds -= n;
+	    }
 	    while (n-- > 0) {
-		objp[0] = (Eterm) COMPRESS_POINTER(next);
+		objp[0] = (Eterm) next;
 		next = objp;
 		objp--;
 	    }
@@ -2756,17 +3233,27 @@ dec_term_atom_common:
 		break;
 	    }
 	    *objp = make_list(hp);
-	    hp += 2*n;
+            hp += 2 * n;
 	    objp = hp - 2;
-	    objp[0] = (Eterm) COMPRESS_POINTER((objp+1));
-	    objp[1] = (Eterm) COMPRESS_POINTER(next);
+	    objp[0] = (Eterm) (objp+1);
+	    objp[1] = (Eterm) next;
 	    next = objp;
 	    objp -= 2;
-	    while (--n > 0) {
-		objp[0] = (Eterm) COMPRESS_POINTER(next);
-		objp[1] = make_list(objp + 2);
+            n--;
+	    if (ctx) {
+                if (reds < n) {
+		    ctx->state = B2TDecodeList;
+		    ctx->u.dc.remaining_n = n - reds;
+		    n = reds;
+		}
+		reds -= n;
+	    }
+            while (n > 0) {
+		objp[0] = (Eterm) next;
+		objp[1] = make_list(next);
 		next = objp;
 		objp -= 2;
+                n--;
 	    }
 	    break;
 	case STRING_EXT:
@@ -2777,6 +3264,14 @@ dec_term_atom_common:
 		break;
 	    }
 	    *objp = make_list(hp);
+            if (ctx) {
+                if (reds < n) {
+                    ctx->state = B2TDecodeString;
+                    ctx->u.dc.remaining_n = n - reds;
+                    n = reds;
+		}
+                reds -= n;
+            }
 	    while (n-- > 0) {
 		hp[0] = make_small(*ep++);
 		hp[1] = make_list(hp+2);
@@ -2804,7 +3299,7 @@ dec_term_atom_common:
 		volatile unsigned long *fpexnp = erts_get_current_fp_exception();
 #endif
 
-#ifdef WORDS_BIGENDIAN
+#if defined(WORDS_BIGENDIAN) || defined(DOUBLE_MIDDLE_ENDIAN)
 		ff.fw[0] = get_int32(ep);
 		ep += 4;
 		ff.fw[1] = get_int32(ep);
@@ -2822,20 +3317,23 @@ dec_term_atom_common:
 		hp += FLOAT_SIZE_OBJECT;
 		break;
 	    }
-	case PID_EXT:
-	    *hpp = hp;
-	    ep = dec_pid(edep, hpp, ep, off_heap, objp);
-	    hp = *hpp;
+        case PID_EXT:
+        case NEW_PID_EXT:
+	    factory->hp = hp;
+	    ep = dec_pid(edep, factory, ep, objp, ep[-1]);
+	    hp = factory->hp;
 	    if (ep == NULL) {
 		goto error;
 	    }
 	    break;
-	case PORT_EXT:
+        case PORT_EXT:
+        case NEW_PORT_EXT:
 	    {
 		Eterm sysname;
 		ErlNode *node;
 		Uint num;
-		Uint cre;
+		Uint32 cre;
+                byte tag = ep[-1];
 
 		if ((ep = dec_atom(edep, ep, &sysname)) == NULL) {
 		    goto error;
@@ -2844,12 +3342,17 @@ dec_term_atom_common:
 		    goto error;
 		}
 		ep += 4;
-		cre = get_int8(ep);
-		ep++;
-		if (!is_valid_creation(cre)) {
-		    goto error;
-		}
-
+                if (tag == PORT_EXT) {
+                    cre = get_int8(ep);
+                    ep++;
+                    if (!is_valid_creation(cre)) {
+                        goto error;
+                    }
+                }
+                else {
+                    cre = get_int32(ep);
+                    ep += 4;
+                }
 		node = dec_get_node(sysname, cre);
 		if(node == erts_this_node) {
 		    *objp = make_internal_port(num);
@@ -2859,11 +3362,11 @@ dec_term_atom_common:
 		    hp += EXTERNAL_THING_HEAD_SIZE + 1;
 		    
 		    etp->header = make_external_port_header(1);
-		    etp->next = off_heap->first;
+		    etp->next = factory->off_heap->first;
 		    etp->node = node;
 		    etp->data.ui[0] = num;
 
-		    off_heap->first = (struct erl_off_heap_header*)etp;
+		    factory->off_heap->first = (struct erl_off_heap_header*)etp;
 		    *objp = make_external_port(etp);
 		}
 
@@ -2874,7 +3377,7 @@ dec_term_atom_common:
 		Eterm sysname;
 		ErlNode *node;
 		int i;
-		Uint cre;
+		Uint32 cre;
 		Uint32 *ref_num;
 		Uint32 r0;
 		Uint ref_words;
@@ -2898,9 +3401,6 @@ dec_term_atom_common:
 		ref_words = get_int16(ep);
 		ep += 2;
 
-		if (ref_words > ERTS_MAX_REF_NUMBERS)
-		    goto error;
-
 		if ((ep = dec_atom(edep, ep, &sysname)) == NULL)
 		    goto error;
 
@@ -2913,15 +3413,30 @@ dec_term_atom_common:
 		ep += 4;
 		if (r0 >= MAX_REFERENCE)
 		    goto error;
+		goto ref_ext_common;
+
+            case NEWER_REFERENCE_EXT:
+		ref_words = get_int16(ep);
+		ep += 2;
+
+		if ((ep = dec_atom(edep, ep, &sysname)) == NULL)
+		    goto error;
+
+		cre = get_int32(ep);
+		ep += 4;
+		r0 = get_int32(ep); /* allow full word */
+		ep += 4;
 
 	    ref_ext_common:
+		if (ref_words > ERTS_MAX_REF_NUMBERS)
+		    goto error;
 
 		node = dec_get_node(sysname, cre);
 		if(node == erts_this_node) {
 		    RefThing *rtp = (RefThing *) hp;
 		    ref_num = (Uint32 *) (hp + REF_THING_HEAD_SIZE);
 
-#if defined(ARCH_64) && !HALFWORD_HEAP
+#if defined(ARCH_64)
 		    hp += REF_THING_HEAD_SIZE + ref_words/2 + 1;
 		    rtp->header = make_ref_thing_header(ref_words/2 + 1);
 #else
@@ -2932,26 +3447,26 @@ dec_term_atom_common:
 		}
 		else {
 		    ExternalThing *etp = (ExternalThing *) hp;
-#if defined(ARCH_64) && !HALFWORD_HEAP
+#if defined(ARCH_64)
 		    hp += EXTERNAL_THING_HEAD_SIZE + ref_words/2 + 1;
 #else
 		    hp += EXTERNAL_THING_HEAD_SIZE + ref_words;
 #endif
 
-#if defined(ARCH_64) && !HALFWORD_HEAP
+#if defined(ARCH_64)
 		    etp->header = make_external_ref_header(ref_words/2 + 1);
 #else
 		    etp->header = make_external_ref_header(ref_words);
 #endif
-		    etp->next = off_heap->first;
+		    etp->next = factory->off_heap->first;
 		    etp->node = node;
 
-		    off_heap->first = (struct erl_off_heap_header*)etp;
+		    factory->off_heap->first = (struct erl_off_heap_header*)etp;
 		    *objp = make_external_ref(etp);
 		    ref_num = &(etp->data.ui32[0]);
 		}
 
-#if defined(ARCH_64) && !HALFWORD_HEAP
+#if defined(ARCH_64)
 		*(ref_num++) = ref_words /* 32-bit arity */;
 #endif
 		ref_num[0] = r0;
@@ -2959,7 +3474,7 @@ dec_term_atom_common:
 		    ref_num[i] = get_int32(ep);
 		    ep += 4;
 		}
-#if defined(ARCH_64) && !HALFWORD_HEAP
+#if defined(ARCH_64)
 		if ((1 + ref_words) % 2)
 		    ref_num[ref_words] = 0;
 #endif
@@ -2970,7 +3485,7 @@ dec_term_atom_common:
 		n = get_int32(ep);
 		ep += 4;
 	    
-		if (n <= ERL_ONHEAP_BIN_LIMIT) {
+		if ((unsigned)n <= ERL_ONHEAP_BIN_LIMIT) {
 		    ErlHeapBin* hb = (ErlHeapBin *) hp;
 
 		    hb->thing_word = header_heap_bin(n);
@@ -2981,21 +3496,32 @@ dec_term_atom_common:
 		} else {
 		    Binary* dbin = erts_bin_nrml_alloc(n);
 		    ProcBin* pb;
-		    dbin->flags = 0;
-		    dbin->orig_size = n;
 		    erts_refc_init(&dbin->refc, 1);
-		    sys_memcpy(dbin->orig_bytes, ep, n);
 		    pb = (ProcBin *) hp;
 		    hp += PROC_BIN_SIZE;
 		    pb->thing_word = HEADER_PROC_BIN;
 		    pb->size = n;
-		    pb->next = off_heap->first;
-		    off_heap->first = (struct erl_off_heap_header*)pb;
+		    pb->next = factory->off_heap->first;
+		    factory->off_heap->first = (struct erl_off_heap_header*)pb;
+		    OH_OVERHEAD(factory->off_heap, pb->size / sizeof(Eterm));
 		    pb->val = dbin;
 		    pb->bytes = (byte*) dbin->orig_bytes;
 		    pb->flags = 0;
 		    *objp = make_binary(pb);
-		}
+                    if (ctx) {
+                        int n_limit = reds * B2T_MEMCPY_FACTOR;
+                        if (n > n_limit) {
+                            ctx->state = B2TDecodeBinary;
+                            ctx->u.dc.remaining_n = n - n_limit;
+                            ctx->u.dc.remaining_bytes = dbin->orig_bytes + n_limit;
+                            n = n_limit;
+                            reds = 0;
+                        }
+                        else
+                            reds -= n / B2T_MEMCPY_FACTOR;
+                    }
+                    sys_memcpy(dbin->orig_bytes, ep, n);
+                }
 		ep += n;
 		break;
 	    }
@@ -3007,8 +3533,10 @@ dec_term_atom_common:
 
 		n = get_int32(ep);
 		bitsize = ep[4];
-		ep += 5;
-		if (n <= ERL_ONHEAP_BIN_LIMIT) {
+                if (((bitsize==0) != (n==0)) || bitsize > 8)
+                    goto error;
+                ep += 5;
+		if ((unsigned)n <= ERL_ONHEAP_BIN_LIMIT) {
 		    ErlHeapBin* hb = (ErlHeapBin *) hp;
 
 		    hb->thing_word = header_heap_bin(n);
@@ -3016,29 +3544,44 @@ dec_term_atom_common:
 		    sys_memcpy(hb->data, ep, n);
 		    bin = make_binary(hb);
 		    hp += heap_bin_size(n);
+                    ep += n;
 		} else {
 		    Binary* dbin = erts_bin_nrml_alloc(n);
 		    ProcBin* pb;
-		    dbin->flags = 0;
-		    dbin->orig_size = n;
+
 		    erts_refc_init(&dbin->refc, 1);
-		    sys_memcpy(dbin->orig_bytes, ep, n);
 		    pb = (ProcBin *) hp;
 		    pb->thing_word = HEADER_PROC_BIN;
 		    pb->size = n;
-		    pb->next = off_heap->first;
-		    off_heap->first = (struct erl_off_heap_header*)pb;
+		    pb->next = factory->off_heap->first;
+		    factory->off_heap->first = (struct erl_off_heap_header*)pb;
+		    OH_OVERHEAD(factory->off_heap, pb->size / sizeof(Eterm));
 		    pb->val = dbin;
 		    pb->bytes = (byte*) dbin->orig_bytes;
 		    pb->flags = 0;
 		    bin = make_binary(pb);
 		    hp += PROC_BIN_SIZE;
-		}
-		ep += n;
-		if (bitsize == 0) {
+                    if (ctx) {
+                        int n_limit = reds * B2T_MEMCPY_FACTOR;
+                        if (n > n_limit) {
+                            ctx->state = B2TDecodeBinary;
+                            ctx->u.dc.remaining_n = n - n_limit;
+                            ctx->u.dc.remaining_bytes = dbin->orig_bytes + n_limit;
+                            n = n_limit;
+                            reds = 0;
+                        }
+                        else
+                            reds -= n / B2T_MEMCPY_FACTOR;
+                    }
+                    sys_memcpy(dbin->orig_bytes, ep, n);
+                    ep += n;
+                    n = pb->size;
+                }
+
+		if (bitsize == 8 || n == 0) {
 		    *objp = bin;
 		} else {
-		    sb = (ErlSubBin *) hp;
+                    sb = (ErlSubBin *)hp;
 		    sb->thing_word = HEADER_SUB_BIN;
 		    sb->orig = bin;
 		    sb->size = n - 1;
@@ -3064,9 +3607,9 @@ dec_term_atom_common:
 		if ((ep = dec_atom(edep, ep, &name)) == NULL) {
 		    goto error;
 		}
-		*hpp = hp;
-		ep = dec_term(edep, hpp, ep, off_heap, &temp);
-		hp = *hpp;
+		factory->hp = hp;
+		ep = dec_term(edep, factory, ep, &temp, NULL);
+		hp = factory->hp;
 		if (ep == NULL) {
 		    goto error;
 		}
@@ -3083,15 +3626,65 @@ dec_term_atom_common:
                 }
 		*objp = make_export(hp);
 		*hp++ = HEADER_EXPORT;
-#if HALFWORD_HEAP
-		*((UWord *) (UWord) hp) =  (UWord) erts_export_get_or_make_stub(mod, name, arity);
-		hp += 2;
-#else
 		*hp++ = (Eterm) erts_export_get_or_make_stub(mod, name, arity);
-#endif
 		break;
 	    }
 	    break;
+	case MAP_EXT:
+	    {
+		Uint32 size,n;
+		Eterm *kptr,*vptr;
+		Eterm keys;
+
+		size = get_int32(ep); ep += 4;
+
+                if (size <= MAP_SMALL_MAP_LIMIT) {
+                    flatmap_t *mp;
+
+                    keys  = make_tuple(hp);
+                    *hp++ = make_arityval(size);
+                    hp   += size;
+                    kptr = hp - 1;
+
+                    mp    = (flatmap_t*)hp;
+                    hp   += MAP_HEADER_FLATMAP_SZ;
+                    hp   += size;
+                    vptr = hp - 1;
+
+                    /* kptr, last word for keys
+                     * vptr, last word for values
+                     */
+
+                    WSTACK_PUSH(flat_maps, (UWord)mp);
+                    mp->thing_word = MAP_HEADER_FLATMAP;
+                    mp->size       = size;
+                    mp->keys       = keys;
+                    *objp          = make_flatmap(mp);
+
+                    for (n = size; n; n--) {
+                        *vptr = (Eterm) next;
+                        *kptr = (Eterm) vptr;
+                        next  = kptr;
+                        vptr--;
+                        kptr--;
+                    }
+                }
+                else {  /* Make hamt */
+                    struct dec_term_hamt* hamt = PSTACK_PUSH(hamt_array);
+
+                    hamt->objp = objp;
+                    hamt->size = size;
+                    hamt->leaf_array = hp;
+
+                    for (n = size; n; n--) {
+                        CDR(hp) = (Eterm) next;
+                        CAR(hp) = (Eterm) &CDR(hp);
+                        next = &CAR(hp);
+                        hp += 2;
+                    }
+                }
+	    }
+	    break;
 	case NEW_FUN_EXT:
 	    {
 		ErlFunThing* funp = (ErlFunThing *) hp;
@@ -3123,9 +3716,9 @@ dec_term_atom_common:
 		if ((ep = dec_atom(edep, ep, &module)) == NULL) {
 		    goto error;
 		}
-		*hpp = hp;
+		factory->hp = hp;
 		/* Index */
-		if ((ep = dec_term(edep, hpp, ep, off_heap, &temp)) == NULL) {
+		if ((ep = dec_term(edep, factory, ep, &temp, NULL)) == NULL) {
 		    goto error;
 		}
 		if (!is_small(temp)) {
@@ -3134,7 +3727,7 @@ dec_term_atom_common:
 		old_index = unsigned_val(temp);
 
 		/* Uniq */
-		if ((ep = dec_term(edep, hpp, ep, off_heap, &temp)) == NULL) {
+		if ((ep = dec_term(edep, factory, ep, &temp, NULL)) == NULL) {
 		    goto error;
 		}
 		if (!is_small(temp)) {
@@ -3146,8 +3739,8 @@ dec_term_atom_common:
 		 * It is safe to link the fun into the fun list only when
 		 * no more validity tests can fail.
 		 */
-		funp->next = off_heap->first;
-		off_heap->first = (struct erl_off_heap_header*)funp;
+		funp->next = factory->off_heap->first;
+		factory->off_heap->first = (struct erl_off_heap_header*)funp;
 
 		funp->fe = erts_put_fun_entry2(module, old_uniq, old_index,
 					       uniq, index, arity);
@@ -3158,15 +3751,15 @@ dec_term_atom_common:
 		}
 		funp->native_address = funp->fe->native_address;
 #endif
-		hp = *hpp;
+		hp = factory->hp;
 
 		/* Environment */
 		for (i = num_free-1; i >= 0; i--) {
-		    funp->env[i] = (Eterm) COMPRESS_POINTER(next);
+		    funp->env[i] = (Eterm) next;
 		    next = funp->env + i;
 		}
 		/* Creator */
-		funp->creator = (Eterm) COMPRESS_POINTER(next);
+		funp->creator = (Eterm) next;
 		next = &(funp->creator);
 		break;
 	    }
@@ -3184,15 +3777,15 @@ dec_term_atom_common:
 		ep += 4;
 		hp += ERL_FUN_SIZE;
 		hp += num_free;
-		*hpp = hp;
+		factory->hp = hp;
 		funp->thing_word = HEADER_FUN;
 		funp->num_free = num_free;
 		*objp = make_fun(funp);
 
 		/* Creator pid */
-		if (*ep != PID_EXT 
-		    || (ep = dec_pid(edep, hpp, ++ep, off_heap,
-				     &funp->creator))==NULL) { 
+		if ((*ep != PID_EXT && *ep != NEW_PID_EXT)
+		    || (ep = dec_pid(edep, factory, ep+1,
+				     &funp->creator, *ep))==NULL) {
 		    goto error;
 		}
 
@@ -3202,7 +3795,7 @@ dec_term_atom_common:
 		}
 
 		/* Index */
-		if ((ep = dec_term(edep, hpp, ep, off_heap, &temp)) == NULL) {
+		if ((ep = dec_term(edep, factory, ep, &temp, NULL)) == NULL) {
 		    goto error;
 		}
 		if (!is_small(temp)) {
@@ -3211,7 +3804,7 @@ dec_term_atom_common:
 		old_index = unsigned_val(temp);
 
 		/* Uniq */
-		if ((ep = dec_term(edep, hpp, ep, off_heap, &temp)) == NULL) {
+		if ((ep = dec_term(edep, factory, ep, &temp, NULL)) == NULL) {
 		    goto error;
 		}
 		if (!is_small(temp)) {
@@ -3222,8 +3815,8 @@ dec_term_atom_common:
 		 * It is safe to link the fun into the fun list only when
 		 * no more validity tests can fail.
 		 */
-		funp->next = off_heap->first;
-		off_heap->first = (struct erl_off_heap_header*)funp;
+		funp->next = factory->off_heap->first;
+		factory->off_heap->first = (struct erl_off_heap_header*)funp;
 		old_uniq = unsigned_val(temp);
 
 		funp->fe = erts_put_fun_entry(module, old_uniq, old_index);
@@ -3231,11 +3824,11 @@ dec_term_atom_common:
 #ifdef HIPE
 		funp->native_address = funp->fe->native_address;
 #endif
-		hp = *hpp;
+		hp = factory->hp;
 
 		/* Environment */
 		for (i = num_free-1; i >= 0; i--) {
-		    funp->env[i] = (Eterm) COMPRESS_POINTER(next);
+		    funp->env[i] = (Eterm) next;
 		    next = funp->env + i;
 		}
 		break;
@@ -3265,8 +3858,9 @@ dec_term_atom_common:
 
 		erts_refc_inc(&pb->val->refc, 1);
 		hp += PROC_BIN_SIZE;
-		pb->next = off_heap->first;
-		off_heap->first = (struct erl_off_heap_header*)pb;
+		pb->next = factory->off_heap->first;
+		factory->off_heap->first = (struct erl_off_heap_header*)pb;
+		OH_OVERHEAD(factory->off_heap, pb->size / sizeof(Eterm));
 		pb->flags = 0;
 		*objp = make_binary(pb);
 		break;
@@ -3282,8 +3876,9 @@ dec_term_atom_common:
 
 		erts_refc_inc(&pb->val->refc, 1);
 		hp += PROC_BIN_SIZE;
-		pb->next = off_heap->first;
-		off_heap->first = (struct erl_off_heap_header*)pb;
+		pb->next = factory->off_heap->first;
+		factory->off_heap->first = (struct erl_off_heap_header*)pb;
+                OH_OVERHEAD(factory->off_heap, pb->size / sizeof(Eterm));
 		pb->flags = 0;
 
 		sub = (ErlSubBin*)hp;
@@ -3301,21 +3896,96 @@ dec_term_atom_common:
 	    }
 
 	default:
-	error:
-	    /* UNDO:
-	     * Must unlink all off-heap objects that may have been
-	     * linked into the process. 
-	     */
-	    if (hp < *hpp) { /* Sometimes we used hp and sometimes *hpp */
-		hp = *hpp;   /* the largest must be the freshest */
-	    }
-	    undo_offheap_in_area(off_heap, hp_saved, hp);
-	    *hpp = hp_saved;
-	    return NULL;
+	    goto error;
 	}
+
+        if (--reds <= 0) {
+            if (ctx) {
+                if (next || ctx->state != B2TDecode) {
+                    ctx->u.dc.ep = ep;
+                    ctx->u.dc.next = next;
+                    ctx->u.dc.factory.hp = hp;
+		    if (!WSTACK_ISEMPTY(flat_maps)) {
+			WSTACK_SAVE(flat_maps, &ctx->u.dc.flat_maps);
+		    }
+		    if (!PSTACK_IS_EMPTY(hamt_array)) {
+			PSTACK_SAVE(hamt_array, &ctx->u.dc.hamt_array);
+		    }
+                    ctx->reds = 0;
+                    return NULL;
+                }
+            }
+            else {
+                reds = ERTS_SWORD_MAX;
+            }
+        }
     }
-    *hpp = hp;
+
+    ASSERT(hp <= factory->hp_end
+           || (factory->mode == FACTORY_CLOSED && is_immed(*dbg_resultp)));
+    factory->hp = hp;
+    /*
+     * From here on factory may produce (more) heap fragments
+     */
+
+    if (!PSTACK_IS_EMPTY(hamt_array)) {
+        do {
+            struct dec_term_hamt* hamt = PSTACK_TOP(hamt_array);
+
+            *hamt->objp = erts_hashmap_from_array(factory,
+                                                  hamt->leaf_array,
+                                                  hamt->size,
+                                                  1);
+            if (is_non_value(*hamt->objp))
+                goto error_hamt;
+
+            (void) PSTACK_POP(hamt_array);
+        } while (!PSTACK_IS_EMPTY(hamt_array));
+        PSTACK_DESTROY(hamt_array);
+    }
+
+    /* Iterate through all the (flat)maps and check for validity and sort keys
+     * - done here for when we know it is complete.
+     */
+
+    while(!WSTACK_ISEMPTY(flat_maps)) {
+        next = (Eterm *)WSTACK_POP(flat_maps);
+        if (!erts_validate_and_sort_flatmap((flatmap_t*)next))
+            goto error;
+    }
+    WSTACK_DESTROY(flat_maps);
+
+    ASSERT((Eterm*)*dbg_resultp != NULL);
+
+    if (ctx) {
+        ctx->state = B2TDone;
+	ctx->reds = reds;
+    }
+
     return ep;
+
+error:
+    /* UNDO:
+     * Must unlink all off-heap objects that may have been
+     * linked into the process. 
+     */
+    if (factory->mode != FACTORY_CLOSED) {
+	if (factory->hp < hp) { /* Sometimes we used hp and sometimes factory->hp */
+	    factory->hp = hp;   /* the largest must be the freshest */
+	}
+    }
+    else ASSERT(factory->hp == hp);
+
+error_hamt:
+    erts_factory_undo(factory);
+    PSTACK_DESTROY(hamt_array);
+    if (ctx) {
+	ctx->state = B2TDecodeFail;
+	ctx->reds = reds;
+    }
+    WSTACK_DESTROY(flat_maps);
+        
+    return NULL;
 }
 
 /* returns the number of bytes needed to encode an object
@@ -3329,63 +3999,38 @@ static Uint encode_size_struct2(ErtsAtomCacheMap *acmp, Eterm obj, unsigned dfla
 }
 
 static int
-encode_size_struct_int(Process *p, ErtsAtomCacheMap *acmp, Eterm obj, 
+encode_size_struct_int(TTBSizeContext* ctx, ErtsAtomCacheMap *acmp, Eterm obj,
 		       unsigned dflags, Sint *reds, Uint *res)
 {
-    DECLARE_ESTACK(s);
+    DECLARE_WSTACK(s);
     Uint m, i, arity;
     Uint result = 0;
-    int count_reds = (p != NULL && reds != 0);
     Sint r = 0;
 
-    if (count_reds) {
-	ESTACK_CHANGE_ALLOCATOR(s, ERTS_ALC_T_EXTRA_ROOT);
+    if (ctx) {
+	WSTACK_CHANGE_ALLOCATOR(s, ERTS_ALC_T_SAVED_ESTACK);
 	r = *reds;
+
+	if (ctx->wstack.wstart) { /* restore saved stack */
+	    WSTACK_RESTORE(s, &ctx->wstack);
+	    result = ctx->result;
+	    obj = ctx->obj;
+	}
     }
 
-    if (p && p->extra_root) { /* restore saved stack */
-	ESTACK_RESTORE(s,p->extra_root->objv, p->extra_root->sz + 1);
-	result = ESTACK_POP(s); /*Untagged, beyond  p->extra_root->sz */
-	obj = ESTACK_POP(s);
+#define LIST_TAIL_OP ((0 << _TAG_PRIMARY_SIZE) | TAG_PRIMARY_HEADER)
+#define TERM_ARRAY_OP(N) (((N) << _TAG_PRIMARY_SIZE) | TAG_PRIMARY_HEADER)
+#define TERM_ARRAY_OP_DEC(OP) ((OP) - (1 << _TAG_PRIMARY_SIZE))
 
-    } 
 
-    goto L_jump_start;
+    for (;;) {
+	ASSERT(!is_header(obj));
 
- outer_loop:
-    while (!ESTACK_ISEMPTY(s)) {
-	obj = ESTACK_POP(s);
-    handle_popped_obj:
-	if (is_list(obj)) {
-	    Eterm* cons = list_val(obj);
-	    Eterm tl;
-
-	    tl = CDR(cons);
-	    obj = CAR(cons);
-	    ESTACK_PUSH(s, tl);
-	} else if (is_nil(obj)) {
-	    result++;
-	    goto outer_loop;
-	} else {
-	    /*
-	     * Other term (in the tail of a non-proper list or
-	     * in a fun's environment).
-	     */
-	}
-    
-    L_jump_start:
-	if (count_reds && --r == 0) {
+	if (ctx && --r == 0) {
 	    *reds = r;
-	    ESTACK_PUSH(s,obj); /* push back current object */
-	    ESTACK_PUSH(s,result); /* Untagged, will be out of GC reach */
-	    if (p->extra_root == NULL) {
-		p->extra_root = erts_alloc(ERTS_ALC_T_EXTRA_ROOT, sizeof(ErlExtraRootSet));
-		p->extra_root->objv = NULL;
-		p->extra_root->sz = 0;
-		p->extra_root->cleanup = cleanup_ttb_extra_root;
-	    }
-	    ESTACK_SAVE(s, p->extra_root->objv, p->extra_root->sz);
-	    --p->extra_root->sz; /* Hide result from GC */
+	    ctx->obj = obj;
+	    ctx->result = result;
+	    WSTACK_SAVE(s, &ctx->wstack);
 	    return -1;
 	}
 	switch (tag_val_def(obj)) {
@@ -3446,20 +4091,29 @@ encode_size_struct_int(Process *p, ErtsAtomCacheMap *acmp, Eterm obj,
 	    else
 		result += 1 + 4 + 1 + i;  /* tag,size,sign,digits */
 	    break;
+        case EXTERNAL_PID_DEF:
+            if (external_pid_creation(obj) > ERTS_MAX_LOCAL_CREATION)
+                result += 3;
+            /*fall through*/
 	case PID_DEF:
-	case EXTERNAL_PID_DEF:
 	    result += (1 + encode_size_struct2(acmp, pid_node_name(obj), dflags) +
 		       4 + 4 + 1);
 	    break;
+        case EXTERNAL_REF_DEF:
+            if (external_ref_creation(obj) > ERTS_MAX_LOCAL_CREATION)
+                result += 3;
+            /*fall through*/
 	case REF_DEF:
-	case EXTERNAL_REF_DEF:
 	    ASSERT(dflags & DFLAG_EXTENDED_REFERENCES);
 	    i = ref_no_of_numbers(obj);
 	    result += (1 + 2 + encode_size_struct2(acmp, ref_node_name(obj), dflags) +
 		       1 + 4*i);
 	    break;
-	case PORT_DEF:
-	case EXTERNAL_PORT_DEF:
+        case EXTERNAL_PORT_DEF:
+            if (external_port_creation(obj) > ERTS_MAX_LOCAL_CREATION)
+                result += 3;
+            /*fall through*/
+        case PORT_DEF:
 	    result += (1 + encode_size_struct2(acmp, port_node_name(obj), dflags) +
 		      4 + 1);
 	    break;
@@ -3468,30 +4122,79 @@ encode_size_struct_int(Process *p, ErtsAtomCacheMap *acmp, Eterm obj,
 		result += m + 2 + 1;
 	    } else {
 		result += 5;
-		goto handle_popped_obj;
+		WSTACK_PUSH2(s, (UWord)CDR(list_val(obj)), (UWord)LIST_TAIL_OP);
+		obj = CAR(list_val(obj));
+		continue; /* big loop */
 	    }
 	    break;
 	case TUPLE_DEF:
 	    {
 		Eterm* ptr = tuple_val(obj);
-		Uint i;
 		arity = arityval(*ptr);
 		if (arity <= 0xff) {
 		    result += 1 + 1;
 		} else {
 		    result += 1 + 4;
 		}
-		for (i = 1; i <= arity; ++i) {
-		    if (is_list(ptr[i])) {
-			if ((m = is_string(obj)) && (m < MAX_STRING_LEN)) {
-			    result += m + 2 + 1;
-			} else {
-			    result += 5;
-			}
+		if (arity > 1) {
+		    WSTACK_PUSH2(s, (UWord) (ptr + 2),
+				    (UWord) TERM_ARRAY_OP(arity-1));
+		}
+                else if (arity == 0) {
+		    break;
+                }
+		obj = ptr[1];
+		continue; /* big loop */
+	    }
+	case MAP_DEF:
+	    if (is_flatmap(obj)) {
+		flatmap_t *mp = (flatmap_t*)flatmap_val(obj);
+		Uint size = flatmap_get_size(mp);
+
+		result += 1 + 4; /* tag + 4 bytes size */
+
+                if (size) {
+		    WSTACK_PUSH4(s, (UWord) flatmap_get_values(mp),
+				    (UWord) TERM_ARRAY_OP(size),
+		                    (UWord) flatmap_get_keys(mp),
+				    (UWord) TERM_ARRAY_OP(size));
+		}
+	    } else {
+		Eterm *ptr;
+		Eterm hdr;
+		Uint node_sz;
+		ptr = boxed_val(obj);
+		hdr = *ptr;
+		ASSERT(is_header(hdr));
+		switch(hdr & _HEADER_MAP_SUBTAG_MASK) {
+		case HAMT_SUBTAG_HEAD_ARRAY:
+		    ptr++;
+		    node_sz = 16;
+		    result += 1 + 4; /* tag + 4 bytes size */
+		    break;
+		case HAMT_SUBTAG_HEAD_BITMAP:
+		    ptr++;
+		    result += 1 + 4; /* tag + 4 bytes size */
+		    /*fall through*/
+		case HAMT_SUBTAG_NODE_BITMAP:
+		    node_sz = hashmap_bitcount(MAP_HEADER_VAL(hdr));
+		    ASSERT(node_sz < 17);
+		    break;
+		default:
+		    erts_exit(ERTS_ERROR_EXIT, "bad header\r\n");
+		}
+
+		ptr++;
+		WSTACK_RESERVE(s, node_sz*2);
+		while(node_sz--) {
+                    if (is_list(*ptr)) {
+			WSTACK_FAST_PUSH(s, CAR(list_val(*ptr)));
+			WSTACK_FAST_PUSH(s, CDR(list_val(*ptr)));
+                    } else {
+			WSTACK_FAST_PUSH(s, *ptr);
 		    }
-		    ESTACK_PUSH(s,ptr[i]);
+		    ptr++;
 		}
-		goto outer_loop;
 	    }
 	    break;
 	case FLOAT_DEF:
@@ -3544,25 +4247,13 @@ encode_size_struct_int(Process *p, ErtsAtomCacheMap *acmp, Eterm obj,
 		    result += 2 * (1 + 4); /* Index + Uniq */
 		    result += 1 + (funp->num_free < 0x100 ? 1 : 4);
 		}
-		for (i = 1; i < funp->num_free; i++) {
-		    obj = funp->env[i];
-
-		    if (is_not_list(obj)) {
-			/* Push any non-list terms on the stack */
-			ESTACK_PUSH(s, obj);
-		    } else {
-			/* Lists must be handled specially. */
-			if ((m = is_string(obj)) && (m < MAX_STRING_LEN)) {
-			    result += m + 2 + 1;
-			} else {
-			    result += 5;
-			    ESTACK_PUSH(s, obj);
-			}
-		    }
+		if (funp->num_free > 1) {
+		    WSTACK_PUSH2(s, (UWord) (funp->env + 1),
+				    (UWord) TERM_ARRAY_OP(funp->num_free-1));
 		}
 		if (funp->num_free != 0) {
 		    obj = funp->env[0];
-		    goto L_jump_start;
+		    continue; /* big loop */
 		}
 		break;
 	    }
@@ -3570,11 +4261,7 @@ encode_size_struct_int(Process *p, ErtsAtomCacheMap *acmp, Eterm obj,
 	case EXPORT_DEF:
 	    {
 		Export* ep = *((Export **) (export_val(obj) + 1));
-#if HALFWORD_HEAP
-		result += 2;
-#else
 		result += 1;
-#endif
 		result += encode_size_struct2(acmp, ep->code[0], dflags);
 		result += encode_size_struct2(acmp, ep->code[1], dflags);
 		result += encode_size_struct2(acmp, make_small(ep->code[2]), dflags);
@@ -3582,36 +4269,83 @@ encode_size_struct_int(Process *p, ErtsAtomCacheMap *acmp, Eterm obj,
 	    break;
 
 	default:
-	    erl_exit(1,"Internal data structure error (in encode_size_struct2)%x\n",
+	    erts_exit(ERTS_ERROR_EXIT,"Internal data structure error (in encode_size_struct2)%x\n",
 		     obj);
 	}
-    }
 
-    DESTROY_ESTACK(s);
-    if (p && p->extra_root) {
-	cleanup_ttb_extra_root(p->extra_root);
-	p->extra_root = NULL;
+	if (WSTACK_ISEMPTY(s)) {
+	    break;
+	}
+	obj = (Eterm) WSTACK_POP(s);
+
+        if (is_header(obj)) {
+            switch (obj) {
+	    case LIST_TAIL_OP:
+		obj = (Eterm) WSTACK_POP(s);
+		if (is_list(obj)) {
+		    Eterm* cons = list_val(obj);
+
+		    WSTACK_PUSH2(s, (UWord)CDR(cons), (UWord)LIST_TAIL_OP);
+		    obj = CAR(cons);
+		}
+		break;
+
+	    case TERM_ARRAY_OP(1):
+		obj = *(Eterm*)WSTACK_POP(s);
+		break;
+	    default: { /* TERM_ARRAY_OP(N) when N > 1 */
+		Eterm* ptr = (Eterm*) WSTACK_POP(s);
+		WSTACK_PUSH2(s, (UWord) (ptr+1),
+			        (UWord) TERM_ARRAY_OP_DEC(obj));
+		obj = *ptr;
+	    }
+	    }
+	}
     }
-    if (count_reds) {
+
+    WSTACK_DESTROY(s);
+    if (ctx) {
+	ASSERT(ctx->wstack.wstart == NULL);
 	*reds = r;
     }
     *res = result;
     return 0;
 }
 
+
+
 static Sint
-decoded_size(byte *ep, byte* endp, int internal_tags)
+decoded_size(byte *ep, byte* endp, int internal_tags, B2TContext* ctx)
 {
-    int heap_size = 0;
+    int heap_size;
     int terms;
-    int atom_extra_skip = 0;
+    int atom_extra_skip;
     Uint n;
+    SWord reds;
+
+    if (ctx) {
+        reds = ctx->reds;
+        if (ctx->u.sc.ep) {
+            heap_size = ctx->u.sc.heap_size;
+            terms = ctx->u.sc.terms;
+            ep = ctx->u.sc.ep;
+            atom_extra_skip = ctx->u.sc.atom_extra_skip;
+            goto init_done;
+        }
+    }
+    else
+        reds = 0; /* not used but compiler warns anyway */
+
+    heap_size = 0;
+    terms = 1;
+    atom_extra_skip = 0;
+init_done:
 
 #define SKIP(sz)				\
     do {					\
 	if ((sz) <= endp-ep) {			\
 	    ep += (sz);				\
-        } else { return -1; };			\
+        } else { goto error; };			\
     } while (0)
 
 #define SKIP2(sz1, sz2)				\
@@ -3619,31 +4353,32 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 	Uint sz = (sz1) + (sz2);		\
 	if (sz1 < sz && (sz) <= endp-ep) {	\
 	    ep += (sz);				\
-        } else { return -1; }			\
+        } else { goto error; }			\
     } while (0)
 
 #define CHKSIZE(sz)				\
     do {					\
-	 if ((sz) > endp-ep) { return -1; }	\
+	 if ((sz) > endp-ep) { goto error; }	\
     } while (0)
 
 #define ADDTERMS(n)				\
     do {					\
         int before = terms;		        \
 	terms += (n);                           \
-	if (terms < before) return -1;     	\
+	if (terms < before) goto error;     	\
     } while (0)
 
-
-    for (terms=1; terms > 0; terms--) {
-	int tag;
-
+    ASSERT(terms > 0);
+    do {
+        int tag;
 	CHKSIZE(1);
 	tag = ep++[0];
 	switch (tag) {
 	case INTEGER_EXT:
 	    SKIP(4);
+#if !defined(ARCH_64)
 	    heap_size += BIG_UINT_HEAP_SIZE;
+#endif
 	    break;
 	case SMALL_INTEGER_EXT:
 	    SKIP(1);
@@ -3658,7 +4393,7 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 	    CHKSIZE(4);
 	    n = get_int32(ep);
 	    if (n > BIG_ARITY_MAX*sizeof(ErtsDigit)) {
-		return -1;
+		goto error;
 	    }
 	    SKIP2(n,4+1);		/* skip, size,sign,digits */
 	    heap_size += 1+1+(n+sizeof(Eterm)-1)/sizeof(Eterm); /* XXX: 1 too much? */
@@ -3667,7 +4402,7 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 	    CHKSIZE(2);
 	    n = get_int16(ep);
 	    if (n > MAX_ATOM_CHARACTERS) {
-		return -1;
+		goto error;
 	    }
 	    SKIP(n+2+atom_extra_skip);
 	    atom_extra_skip = 0;
@@ -3677,7 +4412,7 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 	    n = get_int16(ep);
 	    ep += 2;
 	    if (n > MAX_ATOM_SZ_LIMIT) {
-		return -1;
+		goto error;
 	    }
 	    SKIP(n+atom_extra_skip);
 	    atom_extra_skip = 0;
@@ -3686,7 +4421,7 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 	    CHKSIZE(1);
 	    n = get_int8(ep);
 	    if (n > MAX_ATOM_CHARACTERS) {
-		return -1;
+		goto error;
 	    }
 	    SKIP(n+1+atom_extra_skip);
 	    atom_extra_skip = 0;
@@ -3696,7 +4431,7 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 	    n = get_int8(ep);
 	    ep++;
 	    if (n > MAX_ATOM_SZ_LIMIT) {
-		return -1;
+		goto error;
 	    }
 	    SKIP(n+atom_extra_skip);
 	    atom_extra_skip = 0;
@@ -3705,19 +4440,32 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 	    SKIP(1+atom_extra_skip);
 	    atom_extra_skip = 0;
 	    break;
-	case PID_EXT:
+        case NEW_PID_EXT:
+	    atom_extra_skip = 12;
+	    goto case_PID;
+        case PID_EXT:
 	    atom_extra_skip = 9;
+	case_PID:
 	    /* In case it is an external pid */
 	    heap_size += EXTERNAL_THING_HEAD_SIZE + 1;
 	    terms++;
 	    break;
-	case PORT_EXT:
+        case NEW_PORT_EXT:
+	    atom_extra_skip = 8;
+	    goto case_PORT;
+        case PORT_EXT:
 	    atom_extra_skip = 5;
+	case_PORT:
 	    /* In case it is an external port */
 	    heap_size += EXTERNAL_THING_HEAD_SIZE + 1;
 	    terms++;
 	    break;
-	case NEW_REFERENCE_EXT:
+	case NEWER_REFERENCE_EXT:
+	    atom_extra_skip = 4;
+	    goto case_NEW_REFERENCE;
+        case NEW_REFERENCE_EXT:
+	    atom_extra_skip = 1;
+	case_NEW_REFERENCE:
 	    {
 		int id_words;
 
@@ -3725,12 +4473,12 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 		id_words = get_int16(ep);
 		    
 		if (id_words > ERTS_MAX_REF_NUMBERS)
-		    return -1;
+		    goto error;
 
 		ep += 2;
-		atom_extra_skip = 1 + 4*id_words;
+		atom_extra_skip += 4*id_words;
 		/* In case it is an external ref */
-#if defined(ARCH_64) && !HALFWORD_HEAP
+#if defined(ARCH_64)
 		heap_size += EXTERNAL_THING_HEAD_SIZE + id_words/2 + 1;
 #else
 		heap_size += EXTERNAL_THING_HEAD_SIZE + id_words;
@@ -3767,6 +4515,17 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 	    ADDTERMS(n);
 	    heap_size += n + 1;
 	    break;
+	case MAP_EXT:
+	    CHKSIZE(4);
+	    n = get_int32(ep);
+	    ep += 4;
+	    ADDTERMS(2*n);
+            if (n <= MAP_SMALL_MAP_LIMIT) {
+                heap_size += 3 + n + 1 + n;
+            } else {
+                heap_size += HASHMAP_ESTIMATED_HEAP_SIZE(n);
+            }
+	    break;
 	case STRING_EXT:
 	    CHKSIZE(2);
 	    n = get_int16(ep);
@@ -3805,11 +4564,7 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 	    break;
 	case EXPORT_EXT:
 	    terms += 3;
-#if HALFWORD_HEAP
-	    heap_size += 3;
-#else
 	    heap_size += 2;
-#endif
 	    break;
 	case NEW_FUN_EXT:
 	    {
@@ -3827,7 +4582,7 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 		num_free = get_int32(ep);
 		ep += 4;
 		if (num_free > MAX_ARG) {
-		    return -1;
+		    goto error;
 		}
 		terms += 4 + num_free;
 		heap_size += ERL_FUN_SIZE + num_free;
@@ -3844,24 +4599,47 @@ decoded_size(byte *ep, byte* endp, int internal_tags)
 
 	case BINARY_INTERNAL_REF:
 	    if (!internal_tags) {
-		return -1;
+		goto error;
 	    }
 	    SKIP(sizeof(ProcBin));
 	    heap_size += PROC_BIN_SIZE;
 	    break;
 	case BIT_BINARY_INTERNAL_REF:
 	    if (!internal_tags) {
-		return -1;
+		goto error;
 	    }
 	    SKIP(2+sizeof(ProcBin));
 	    heap_size += PROC_BIN_SIZE + ERL_SUB_BIN_SIZE;
 	    break;
 	default:
-	    return -1;
+	    goto error;
 	}
-    }
+        terms--;
+
+        if (ctx && --reds <= 0 && terms > 0) {
+            ctx->u.sc.heap_size = heap_size;
+            ctx->u.sc.terms = terms;
+            ctx->u.sc.ep = ep;
+            ctx->u.sc.atom_extra_skip = atom_extra_skip;
+            ctx->reds = 0;
+            return 0;
+        }
+    }while (terms > 0);
+
     /* 'terms' may be non-zero if it has wrapped around */
-    return terms==0 ? heap_size : -1;
+    if (terms == 0) {
+        if (ctx) {
+            ctx->state = B2TDecodeInit;
+            ctx->reds = reds;
+        }
+        return heap_size;
+    }
+
+error:
+    if (ctx) {
+        ctx->state = B2TBadArg;
+    }
+    return -1;
 #undef SKIP
 #undef SKIP2
 #undef CHKSIZE