Add new AtU8 beam chunk

The new chunk stores atoms encoded in UTF-8.

beam_lib has also been modified to handle the new
'utf8_atoms' attribute while the 'atoms' attribute
may be a missing chunk from now on.

The binary_to_atom/2 BIF can now encode any utf8
binary with up to 255 characters.

The list_to_atom/1 BIF can now accept codepoints
higher than 255 with up to 255 characters (thanks
to Björn Gustavsson).

3 files changed, 41 insertions, 21 deletions

diff --git a/lib/compiler/src/beam_asm.erl b/lib/compiler/src/beam_asm.erl
index a2f5dc674c..2fc2850591 100644
--- a/lib/compiler/src/beam_asm.erl
+++ b/lib/compiler/src/beam_asm.erl
@@ -21,7 +21,7 @@
 
 -module(beam_asm).
 
--export([module/4]).
+-export([module/5]).
 -export([encode/2]).
 
 -export_type([fail/0,label/0,reg/0,src/0,module_code/0,function_name/0]).
@@ -57,20 +57,20 @@
 -type module_code() ::
         {module(),[_],[_],[asm_function()],pos_integer()}.
 
--spec module(module_code(), exports(), [_], [compile:option()]) ->
+-spec module(module_code(), exports(), [_], [compile:option()], [compile:option()]) ->
                     {'ok',binary()}.
 
-module(Code, Abst, SourceFile, Opts) ->
-    {ok,assemble(Code, Abst, SourceFile, Opts)}.
+module(Code, Abst, SourceFile, Opts, CompilerOpts) ->
+    {ok,assemble(Code, Abst, SourceFile, Opts, CompilerOpts)}.
 
-assemble({Mod,Exp0,Attr0,Asm0,NumLabels}, Abst, SourceFile, Opts) ->
+assemble({Mod,Exp0,Attr0,Asm0,NumLabels}, Abst, SourceFile, Opts, CompilerOpts) ->
     {1,Dict0} = beam_dict:atom(Mod, beam_dict:new()),
     {0,Dict1} = beam_dict:fname(atom_to_list(Mod) ++ ".erl", Dict0),
     NumFuncs = length(Asm0),
     {Asm,Attr} = on_load(Asm0, Attr0),
     Exp = cerl_sets:from_list(Exp0),
     {Code,Dict2} = assemble_1(Asm, Exp, Dict1, []),
-    build_file(Code, Attr, Dict2, NumLabels, NumFuncs, Abst, SourceFile, Opts).
+    build_file(Code, Attr, Dict2, NumLabels, NumFuncs, Abst, SourceFile, Opts, CompilerOpts).
 
 on_load(Fs0, Attr0) ->
     case proplists:get_value(on_load, Attr0) of
@@ -113,7 +113,7 @@ assemble_function([H|T], Acc, Dict0) ->
 assemble_function([], Code, Dict) ->
     {Code, Dict}.
 
-build_file(Code, Attr, Dict, NumLabels, NumFuncs, Abst, SourceFile, Opts) ->
+build_file(Code, Attr, Dict, NumLabels, NumFuncs, Abst, SourceFile, Opts, CompilerOpts) ->
     %% Create the code chunk.
 
     CodeChunk = chunk(<<"Code">>,
@@ -125,9 +125,9 @@ build_file(Code, Attr, Dict, NumLabels, NumFuncs, Abst, SourceFile, Opts) ->
 		      Code),
 
     %% Create the atom table chunk.
-
-    {NumAtoms, AtomTab} = beam_dict:atom_table(Dict),
-    AtomChunk = chunk(<<"Atom">>, <<NumAtoms:32>>, AtomTab),
+    AtomEncoding = atom_encoding(CompilerOpts),
+    {NumAtoms, AtomTab} = beam_dict:atom_table(Dict, AtomEncoding),
+    AtomChunk = chunk(atom_chunk_name(AtomEncoding), <<NumAtoms:32>>, AtomTab),
 
     %% Create the import table chunk.
 
@@ -203,6 +203,15 @@ build_file(Code, Attr, Dict, NumLabels, NumFuncs, Abst, SourceFile, Opts) ->
 	     end,
     build_form(<<"BEAM">>, Chunks).
 
+atom_encoding(Opts) ->
+    case proplists:get_bool(no_utf8_atoms, Opts) of
+	false -> utf8;
+	true -> latin1
+    end.
+
+atom_chunk_name(utf8) -> <<"AtU8">>;
+atom_chunk_name(latin1) -> <<"Atom">>.
+
 %% finalize_fun_table(Essentials, MD5) -> FinalizedEssentials
 %%  Update the 'old_uniq' field in the entry for each fun in the
 %%  'FunT' chunk. We'll use part of the MD5 for the module as a
diff --git a/lib/compiler/src/beam_dict.erl b/lib/compiler/src/beam_dict.erl
index 719d799fd7..990e86062a 100644
--- a/lib/compiler/src/beam_dict.erl
+++ b/lib/compiler/src/beam_dict.erl
@@ -24,7 +24,7 @@
 -export([new/0,opcode/2,highest_opcode/1,
 	 atom/2,local/4,export/4,import/4,
 	 string/2,lambda/3,literal/2,line/2,fname/2,
-	 atom_table/1,local_table/1,export_table/1,import_table/1,
+	 atom_table/2,local_table/1,export_table/1,import_table/1,
 	 string_table/1,lambda_table/1,literal_table/1,
 	 line_table/1]).
 
@@ -197,15 +197,15 @@ fname(Name, #asm{fnames=Fnames}=Dict) ->
     end.
 
 %% Returns the atom table.
-%%    atom_table(Dict) -> {LastIndex,[Length,AtomString...]}
--spec atom_table(bdict()) -> {non_neg_integer(), [[non_neg_integer(),...]]}.
+%%    atom_table(Dict, Encoding) -> {LastIndex,[Length,AtomString...]}
+-spec atom_table(bdict(), latin1 | utf8) -> {non_neg_integer(), [[non_neg_integer(),...]]}.
 
-atom_table(#asm{atoms=Atoms}) ->
+atom_table(#asm{atoms=Atoms}, Encoding) ->
     NumAtoms = maps:size(Atoms),
     Sorted = lists:keysort(2, maps:to_list(Atoms)),
     {NumAtoms,[begin
-                   L = atom_to_list(A),
-                   [length(L)|L]
+                   L = atom_to_binary(A, Encoding),
+                   [byte_size(L),L]
                end || {A,_} <- Sorted]}.
 
 %% Returns the table of local functions.
diff --git a/lib/compiler/src/compile.erl b/lib/compiler/src/compile.erl
index 069add7890..dcd962df66 100644
--- a/lib/compiler/src/compile.erl
+++ b/lib/compiler/src/compile.erl
@@ -214,11 +214,21 @@ expand_opt(report, Os) ->
 expand_opt(return, Os) ->
     [return_errors,return_warnings|Os];
 expand_opt(r12, Os) ->
-    [no_recv_opt,no_line_info|Os];
+    [no_recv_opt,no_line_info,no_utf8_atoms|Os];
 expand_opt(r13, Os) ->
-    [no_recv_opt,no_line_info|Os];
+    [no_recv_opt,no_line_info,no_utf8_atoms|Os];
 expand_opt(r14, Os) ->
-    [no_line_info|Os];
+    [no_line_info,no_utf8_atoms|Os];
+expand_opt(r15, Os) ->
+    [no_utf8_atoms|Os];
+expand_opt(r16, Os) ->
+    [no_utf8_atoms|Os];
+expand_opt(r17, Os) ->
+    [no_utf8_atoms|Os];
+expand_opt(r18, Os) ->
+    [no_utf8_atoms|Os];
+expand_opt(r19, Os) ->
+    [no_utf8_atoms|Os];
 expand_opt({debug_info_key,_}=O, Os) ->
     [encrypt_debug_info,O|Os];
 expand_opt(no_float_opt, Os) ->
@@ -1376,13 +1386,14 @@ encrypt({des3_cbc=Type,Key,IVec,BlockSize}, Bin0) ->
 save_core_code(Code, St) ->
     {ok,Code,St#compile{core_code=cerl:from_records(Code)}}.
 
-beam_asm(Code0, #compile{ifile=File,abstract_code=Abst,mod_options=Opts0}=St) ->
+beam_asm(Code0, #compile{ifile=File,abstract_code=Abst,
+			 options=CompilerOpts,mod_options=Opts0}=St) ->
     Source = paranoid_absname(File),
     Opts1 = lists:map(fun({debug_info_key,_}) -> {debug_info_key,'********'};
 			 (Other) -> Other
 		      end, Opts0),
     Opts2 = [O || O <- Opts1, effects_code_generation(O)],
-    case beam_asm:module(Code0, Abst, Source, Opts2) of
+    case beam_asm:module(Code0, Abst, Source, Opts2, CompilerOpts) of
 	{ok,Code} -> {ok,Code,St#compile{abstract_code=[]}}
     end.