Add optimistic DFLAG_DIST_HOPEFULLY for pending connections

to avoid tuple fallbacks for export funs and bitstrings.

ToDo: Re-encode if receiver turn out to be erl_interface/jinterface.

4 files changed, 11 insertions, 6 deletions

diff --git a/erts/emulator/beam/dist.c b/erts/emulator/beam/dist.c
index 6d2e907f18..7877865ad4 100644
--- a/erts/emulator/beam/dist.c
+++ b/erts/emulator/beam/dist.c
@@ -3443,7 +3443,7 @@ BIF_RETTYPE new_connection_id_1(BIF_ALIST_1)
 	conn_id = dep->connection_id;
     else if (dep->status == 0) {
 	dep->status = ERTS_DE_SFLG_PENDING;
-	dep->flags = DFLAG_DIST_MANDATORY | DFLAG_PENDING_CONNECTION;
+	dep->flags = (DFLAG_DIST_MANDATORY | DFLAG_DIST_HOPEFULLY);
 	dep->connection_id++;
 	dep->connection_id &= ERTS_DIST_CON_ID_MASK;
 	conn_id = dep->connection_id;
diff --git a/erts/emulator/beam/dist.h b/erts/emulator/beam/dist.h
index 505d510473..f9a2037687 100644
--- a/erts/emulator/beam/dist.h
+++ b/erts/emulator/beam/dist.h
@@ -45,7 +45,7 @@
 #define DFLAG_MAP_TAG             0x20000
 #define DFLAG_BIG_CREATION        0x40000
 #define DFLAG_SEND_SENDER         0x80000
-#define DFLAG_PENDING_CONNECTION  0x100000
+#define DFLAG_NO_MAGIC            0x100000
 
 /* Mandatory flags for distribution (sync with dist_util.erl) */
 #define DFLAG_DIST_MANDATORY (DFLAG_EXTENDED_REFERENCES         \
@@ -53,6 +53,11 @@
 			      | DFLAG_UTF8_ATOMS                \
 			      | DFLAG_NEW_FUN_TAGS)
 
+/* Additional optimistic flags when encoding toward pending connection */
+#define DFLAG_DIST_HOPEFULLY (DFLAG_NO_MAGIC                    \
+                              | DFLAG_EXPORT_PTR_TAG            \
+                              | DFLAG_BIT_BINARIES)
+
 /* All flags that should be enabled when term_to_binary/1 is used. */
 #define TERM_TO_BINARY_DFLAGS (DFLAG_EXTENDED_REFERENCES	\
 			       | DFLAG_NEW_FUN_TAGS		\
@@ -206,7 +211,7 @@ retry:
 	    Eterm msg, conn_id;
 
 	    dep->status = ERTS_DE_SFLG_PENDING;
-	    dep->flags = DFLAG_DIST_MANDATORY | DFLAG_PENDING_CONNECTION;
+	    dep->flags = (DFLAG_DIST_MANDATORY | DFLAG_DIST_HOPEFULLY);
 	    dep->connection_id++;
 	    dep->connection_id &= ERTS_DIST_CON_ID_MASK;
             conn_id = make_small(dep->connection_id);
diff --git a/erts/emulator/beam/erl_node_tables.c b/erts/emulator/beam/erl_node_tables.c
index dd607f438e..2a33766ac8 100644
--- a/erts/emulator/beam/erl_node_tables.c
+++ b/erts/emulator/beam/erl_node_tables.c
@@ -628,7 +628,7 @@ erts_set_dist_entry_connected(DistEntry *dep, Eterm cid, Uint flags)
 	dep->connection_id &= ERTS_DIST_CON_ID_MASK;
     }
     dep->status |= ERTS_DE_SFLG_CONNECTED;
-    dep->flags = flags & ~DFLAG_PENDING_CONNECTION;
+    dep->flags = flags & ~DFLAG_NO_MAGIC;
     dep->cid = cid;
     erts_atomic_set_nob(&dep->input_handler,
                             (erts_aint_t) cid);
diff --git a/erts/emulator/beam/external.c b/erts/emulator/beam/external.c
index d8f52ceb57..bfac48580c 100644
--- a/erts/emulator/beam/external.c
+++ b/erts/emulator/beam/external.c
@@ -561,7 +561,7 @@ int erts_encode_dist_ext_size_int(Eterm term, struct erts_dsig_send_context* ctx
 	return -1;
     } else {
 #ifndef ERTS_DEBUG_USE_DIST_SEP
-	if (!(ctx->flags & (DFLAG_DIST_HDR_ATOM_CACHE | DFLAG_PENDING_CONNECTION)))
+	if (!(ctx->flags & (DFLAG_DIST_HDR_ATOM_CACHE | DFLAG_NO_MAGIC)))
 #endif
 	    sz++ /* VERSION_MAGIC */;
 
@@ -593,7 +593,7 @@ int erts_encode_dist_ext(Eterm term, byte **ext, Uint32 flags, ErtsAtomCacheMap
 {
     if (!ctx || !ctx->wstack.wstart) {
     #ifndef ERTS_DEBUG_USE_DIST_SEP
-	if (!(flags & (DFLAG_DIST_HDR_ATOM_CACHE | DFLAG_PENDING_CONNECTION)))
+	if (!(flags & (DFLAG_DIST_HDR_ATOM_CACHE | DFLAG_NO_MAGIC)))
     #endif
 	    *(*ext)++ = VERSION_MAGIC;
     }