Revert "erts: Do not generate atoms on old latin1 external format"

This reverts commit 65b04e233e09e3cc2e0fda3c28e155b95c5a4baf.

2 files changed, 36 insertions, 4 deletions

diff --git a/erts/emulator/beam/dist.h b/erts/emulator/beam/dist.h
index 93a651b24d..3e17645997 100644
--- a/erts/emulator/beam/dist.h
+++ b/erts/emulator/beam/dist.h
@@ -53,7 +53,6 @@
 			       | DFLAG_EXPORT_PTR_TAG		\
 			       | DFLAG_BIT_BINARIES             \
 			       | DFLAG_MAP_TAG                  \
-                               | DFLAG_UTF8_ATOMS               \
                                | DFLAG_BIG_CREATION)
 
 /* opcodes used in distribution messages */
diff --git a/erts/emulator/beam/external.c b/erts/emulator/beam/external.c
index 1190d90b8e..06213daa67 100644
--- a/erts/emulator/beam/external.c
+++ b/erts/emulator/beam/external.c
@@ -2090,6 +2090,7 @@ enc_atom(ErtsAtomCacheMap *acmp, Eterm atom, byte *ep, Uint32 dflags)
 {
     int iix;
     int len;
+    int utf8_atoms = (int) (dflags & DFLAG_UTF8_ATOMS);
 
     ASSERT(is_atom(atom));
 
@@ -2118,8 +2119,8 @@ enc_atom(ErtsAtomCacheMap *acmp, Eterm atom, byte *ep, Uint32 dflags)
     if (iix < 0) {
 	Atom *a = atom_tab(atom_val(atom));
 	len = a->len;
-        {
-            if (len > 255) {
+	if (utf8_atoms || a->latin1_chars < 0) {
+	    if (len > 255) {
 		*ep++ = ATOM_UTF8_EXT;
 		put_int16(len, ep);
 		ep += 2;
@@ -2131,6 +2132,32 @@ enc_atom(ErtsAtomCacheMap *acmp, Eterm atom, byte *ep, Uint32 dflags)
 	    }
 	    sys_memcpy((char *) ep, (char *) a->name, len);
 	}
+	else {
+	    if (a->latin1_chars <= 255 && (dflags & DFLAG_SMALL_ATOM_TAGS)) {
+		*ep++ = SMALL_ATOM_EXT;
+		if (len == a->latin1_chars) {
+		    sys_memcpy(ep+1, a->name, len);
+		}
+		else {
+		    len = erts_utf8_to_latin1(ep+1, a->name, len);
+		    ASSERT(len == a->latin1_chars);
+		}
+		put_int8(len, ep);
+		ep++;
+	    }
+	    else {
+		*ep++ = ATOM_EXT;
+		if (len == a->latin1_chars) {
+		    sys_memcpy(ep+2, a->name, len);
+		}
+		else {
+		    len = erts_utf8_to_latin1(ep+2, a->name, len);
+		    ASSERT(len == a->latin1_chars);
+		}
+		put_int16(len, ep);
+		ep += 2;
+	    }	    
+	}
 	ep += len;
 	return ep;
     }
@@ -4053,13 +4080,19 @@ encode_size_struct_int(TTBSizeContext* ctx, ErtsAtomCacheMap *acmp, Eterm obj,
 	    else {
 		Atom *a = atom_tab(atom_val(obj));
 		int alen;
-                {
+		if ((dflags & DFLAG_UTF8_ATOMS) || a->latin1_chars < 0) {
 		    alen = a->len;
 		    result += 1 + 1 + alen;
 		    if (alen > 255) {
 			result++; /* ATOM_UTF8_EXT (not small) */
 		    }
 		}
+		else {
+		    alen = a->latin1_chars;
+		    result += 1 + 1 + alen;
+		    if (alen > 255 || !(dflags & DFLAG_SMALL_ATOM_TAGS))
+			result++; /* ATOM_EXT (not small) */
+		}
 		insert_acache_map(acmp, obj, dflags);
 	    }
 	    break;