1 files changed, 57 insertions, 2 deletions

diff --git a/erts/emulator/beam/external.c b/erts/emulator/beam/external.c
index ec67ab2aed..ce61cdf040 100644
--- a/erts/emulator/beam/external.c
+++ b/erts/emulator/beam/external.c
@@ -1062,11 +1062,38 @@ bad_dist_ext(ErtsDistExternal *edep)
 }
 
 Sint
-erts_decode_dist_ext_size(ErtsDistExternal *edep, int kill_connection)
+erts_decode_dist_ext_size(ErtsDistExternal *edep, int kill_connection, int payload)
 {
     Sint res;
     byte *ep;
 
+    if (edep->data->frag_id > 1 && payload) {
+        Uint sz = 0;
+        Binary *bin;
+        int i;
+        byte *ep;
+
+        for (i = 0; i < edep->data->frag_id; i++)
+            sz += edep->data[i].ext_endp - edep->data[i].extp;
+
+        bin = erts_bin_nrml_alloc(sz);
+        ep = (byte*)bin->orig_bytes;
+
+        for (i = 0; i < edep->data->frag_id; i++) {
+            sys_memcpy(ep, edep->data[i].extp, edep->data[i].ext_endp - edep->data[i].extp);
+            ep += edep->data[i].ext_endp - edep->data[i].extp;
+            erts_bin_release(edep->data[i].binp);
+            edep->data[i].binp = NULL;
+            edep->data[i].extp = NULL;
+            edep->data[i].ext_endp = NULL;
+        }
+
+        edep->data->frag_id = 1;
+        edep->data->extp = (byte*)bin->orig_bytes;
+        edep->data->ext_endp = ep;
+        edep->data->binp = bin;
+    }
+
     if (edep->data->extp >= edep->data->ext_endp)
 	goto fail;
 #ifndef ERTS_DEBUG_USE_DIST_SEP
@@ -1164,6 +1191,7 @@ Eterm erts_decode_ext(ErtsHeapFactory* factory, byte **ext, Uint32 flags)
     if (flags) {
         ASSERT(flags == ERTS_DIST_EXT_BTT_SAFE);
         ede.flags = flags; /* a dummy struct just for the flags */
+        ede.data = NULL;
         edep = &ede;
     } else {
         edep = NULL;
@@ -1233,8 +1261,10 @@ BIF_RETTYPE erts_debug_dist_ext_to_term_2(BIF_ALIST_2)
 
     ede.data->extp = binary_bytes(real_bin)+offset;
     ede.data->ext_endp = ede.data->extp + size;
+    ede.data->frag_id = 1;
+    ede.data->binp = NULL;
 
-    hsz = erts_decode_dist_ext_size(&ede, 1);
+    hsz = erts_decode_dist_ext_size(&ede, 1, 1);
     if (hsz < 0)
 	goto badarg;
 
@@ -1765,6 +1795,7 @@ static BIF_RETTYPE binary_to_term_int(Process* p, Eterm bin, B2TContext *ctx)
         case B2TDecodeBinary: {
 	    ErtsDistExternal fakedep;
             fakedep.flags = ctx->flags;
+            fakedep.data = NULL;
             dec_term(&fakedep, NULL, NULL, NULL, ctx);
             break;
 	}
@@ -3762,6 +3793,30 @@ dec_term_atom_common:
 		    hp += heap_bin_size(n);
 		    sys_memcpy(hb->data, ep, n);
 		    *objp = make_binary(hb);
+		} else if (edep && edep->data && edep->data->binp &&
+                           n > (edep->data->binp->orig_size / 4)) {
+                    /* If we decode a refc binary from a distribution data
+                       entry we know that it is a refc binary to begin with
+                       so we just increment it and use the reference. This
+                       means that the entire distribution data entry will
+                       remain until this binary is de-allocated so we only
+                       do it if a substantial part (> 25%) of the data
+                       is a binary. */
+                    ProcBin* pb = (ProcBin *) hp;
+                    Binary* bptr = edep->data->binp;
+                    erts_refc_inc(&bptr->intern.refc, 1);
+                    pb->thing_word = HEADER_PROC_BIN;
+                    pb->size = n;
+                    pb->next = factory->off_heap->first;
+                    factory->off_heap->first = (struct erl_off_heap_header*)pb;
+                    pb->val = bptr;
+                    pb->bytes = (byte*) ep;
+                    ERTS_ASSERT((byte*)(bptr->orig_bytes) < ep &&
+                                ep+n <= (byte*)(bptr->orig_bytes+bptr->orig_size));
+                    pb->flags = 0;
+                    OH_OVERHEAD(factory->off_heap, pb->size / sizeof(Eterm));
+                    hp += PROC_BIN_SIZE;
+                    *objp = make_binary(pb);
 		} else {
 		    Binary* dbin = erts_bin_nrml_alloc(n);