erts: Add new module 'atomics'

2 files changed, 148 insertions, 0 deletions

diff --git a/erts/emulator/test/Makefile b/erts/emulator/test/Makefile
index d201ea6ee1..fc395899b8 100644
--- a/erts/emulator/test/Makefile
+++ b/erts/emulator/test/Makefile
@@ -33,6 +33,7 @@ MODULES= \
 	after_SUITE \
 	alloc_SUITE \
 	async_ports_SUITE \
+	atomics_SUITE \
 	beam_SUITE \
 	beam_literals_SUITE \
 	bif_SUITE \
diff --git a/erts/emulator/test/atomics_SUITE.erl b/erts/emulator/test/atomics_SUITE.erl
new file mode 100644
index 0000000000..8c42354770
--- /dev/null
+++ b/erts/emulator/test/atomics_SUITE.erl
@@ -0,0 +1,147 @@
+%%
+%% %CopyrightBegin%
+%%
+%% Copyright Ericsson AB 2018. All Rights Reserved.
+%%
+%% 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
+%%
+%%     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%
+%%
+-module(atomics_SUITE).
+
+-include_lib("common_test/include/ct.hrl").
+
+-compile(export_all).
+
+suite() -> [{ct_hooks,[ts_install_cth]}].
+
+all() ->
+    [signed, unsigned, bad, signed_limits, unsigned_limits].
+
+signed(Config) when is_list(Config) ->
+    Size = 10,
+    Ref = atomics:new(Size,[]),
+    #{size:=Size, memory:=Memory} = atomics:info(Ref),
+    {_,true} = {Memory, Memory > Size*8},
+    {_,true} = {Memory, Memory < Size*max_atomic_sz() + 100},
+    [signed_do(Ref, Ix) || Ix <- lists:seq(1, Size)],
+    ok.
+
+signed_do(Ref, Ix) ->
+    0 = atomics:get(Ref, Ix),
+    ok = atomics:put(Ref, Ix, 3),
+    ok = atomics:add(Ref, Ix, 14),
+    17 = atomics:get(Ref, Ix),
+    20 = atomics:add_get(Ref, Ix, 3),
+    -3 = atomics:add_get(Ref, Ix, -23),
+    17 = atomics:add_get(Ref, Ix, 20),
+    ok = atomics:sub(Ref, Ix, 4),
+    13 = atomics:get(Ref, Ix),
+    -7 = atomics:sub_get(Ref, Ix, 20),
+    3  = atomics:sub_get(Ref, Ix, -10),
+    3  = atomics:exchange(Ref, Ix, 666),
+    ok = atomics:compare_exchange(Ref, Ix, 666, 777),
+    777 = atomics:compare_exchange(Ref, Ix, 666, -666),
+    ok.
+
+unsigned(Config) when is_list(Config) ->
+    Size = 10,
+    Ref = atomics:new(Size,[{signed, false}]),
+    #{size:=Size, memory:=Memory} = atomics:info(Ref),
+    true = Memory > Size*8,
+    true = Memory < Size*max_atomic_sz() + 100,
+    [unsigned_do(Ref, Ix) || Ix <- lists:seq(1, Size)],
+    ok.
+
+unsigned_do(Ref, Ix) ->
+    0 = atomics:get(Ref, Ix),
+    ok = atomics:put(Ref, Ix, 3),
+    ok = atomics:add(Ref, Ix, 14),
+    17 = atomics:get(Ref, Ix),
+    20 = atomics:add_get(Ref, Ix, 3),
+    ok = atomics:sub(Ref, Ix, 7),
+    13 = atomics:get(Ref, Ix),
+    3  = atomics:sub_get(Ref, Ix, 10),
+    3  = atomics:exchange(Ref, Ix, 666),
+    ok = atomics:compare_exchange(Ref, Ix, 666, 777),
+    777 = atomics:compare_exchange(Ref, Ix, 666, 888),
+    ok.
+
+bad(Config) when is_list(Config) ->
+    {'EXIT',{badarg,_}} = (catch atomics:new(0,[])),
+    {'EXIT',{badarg,_}} = (catch atomics:new(10,[bad])),
+    {'EXIT',{badarg,_}} = (catch atomics:new(10,[{signed,bad}])),
+    {'EXIT',{badarg,_}} = (catch atomics:new(10,[{signed,true}, bad])),
+    {'EXIT',{badarg,_}} = (catch atomics:new(10,[{signed,false} | bad])),
+    Ref = atomics:new(10,[]),
+    {'EXIT',{badarg,_}} = (catch atomics:get(1742, 7)),
+    {'EXIT',{badarg,_}} = (catch atomics:get(make_ref(), 7)),
+    {'EXIT',{badarg,_}} = (catch atomics:get(Ref, -1)),
+    {'EXIT',{badarg,_}} = (catch atomics:get(Ref, 0)),
+    {'EXIT',{badarg,_}} = (catch atomics:get(Ref, 11)),
+    {'EXIT',{badarg,_}} = (catch atomics:get(Ref, 7.0)),
+    ok.
+
+
+signed_limits(Config) when is_list(Config) ->
+    Bits = 64,
+    Max = (1 bsl (Bits-1)) - 1,
+    Min = -(1 bsl (Bits-1)),
+
+    Ref = atomics:new(1,[{signed, true}]),
+    #{max:=Max, min:=Min} = atomics:info(Ref),
+    0 = atomics:get(Ref, 1),
+    ok = atomics:add(Ref, 1, Max),
+    Min = atomics:add_get(Ref, 1, 1),
+    Max = atomics:sub_get(Ref, 1, 1),
+
+    IncrMax = (Max bsl 1) bor 1,
+    ok = atomics:put(Ref, 1, 0),
+    ok = atomics:add(Ref, 1, IncrMax),
+    -1 = atomics:get(Ref, 1),
+    {'EXIT',{badarg,_}} = (catch atomics:add(Ref, 1, IncrMax+1)),
+    {'EXIT',{badarg,_}} = (catch atomics:add(Ref, 1, Min-1)),
+
+    ok.
+
+unsigned_limits(Config) when is_list(Config) ->
+    Bits = 64,
+    Max = (1 bsl Bits) - 1,
+    Min = 0,
+
+    Ref = atomics:new(1,[{signed,false}]),
+    #{max:=Max, min:=Min} = atomics:info(Ref),
+    0 = atomics:get(Ref, 1),
+    ok = atomics:add(Ref, 1, Max),
+    Min = atomics:add_get(Ref, 1, 1),
+    Max = atomics:sub_get(Ref, 1, 1),
+
+    {'EXIT',{badarg,_}} = (catch atomics:add(Ref, 1, Max+1)),
+    IncrMin = -(1 bsl (Bits-1)),
+    ok = atomics:put(Ref, 1, -IncrMin),
+    ok = atomics:add(Ref, 1, IncrMin),
+    0 = atomics:get(Ref, 1),
+    {'EXIT',{badarg,_}} = (catch atomics:add(Ref, 1, IncrMin-1)),
+
+    ok.
+
+max_atomic_sz() ->
+    case erlang:system_info({wordsize, external}) of
+        4 -> 16;
+        8 ->
+            EI = erlang:system_info(ethread_info),
+            case lists:keyfind("64-bit native atomics", 1, EI) of
+                {_, "no", _} -> 16;
+                _ -> 8
+            end
+    end.