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-rw-r--r--erts/emulator/test/big_SUITE.erl48
1 files changed, 45 insertions, 3 deletions
diff --git a/erts/emulator/test/big_SUITE.erl b/erts/emulator/test/big_SUITE.erl
index c308760211..29508ffc7c 100644
--- a/erts/emulator/test/big_SUITE.erl
+++ b/erts/emulator/test/big_SUITE.erl
@@ -1,7 +1,7 @@
%%
%% %CopyrightBegin%
%%
-%% Copyright Ericsson AB 1997-2016. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2018. 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.
@@ -24,7 +24,7 @@
-export([t_div/1, eq_28/1, eq_32/1, eq_big/1, eq_math/1, big_literals/1,
borders/1, negative/1, big_float_1/1, big_float_2/1,
- bxor_2pow/1,
+ bxor_2pow/1, band_2pow/1,
shift_limit_1/1, powmod/1, system_limit/1, toobig/1, otp_6692/1]).
%% Internal exports.
@@ -43,7 +43,7 @@ suite() ->
all() ->
[t_div, eq_28, eq_32, eq_big, eq_math, big_literals,
borders, negative, {group, big_float}, shift_limit_1,
- bxor_2pow,
+ bxor_2pow, band_2pow,
powmod, system_limit, toobig, otp_6692].
groups() ->
@@ -339,6 +339,13 @@ system_limit(Config) when is_list(Config) ->
{'EXIT',{system_limit,_}} = (catch apply(erlang, id('bsl'), [Maxbig,2])),
{'EXIT',{system_limit,_}} = (catch id(1) bsl (1 bsl 45)),
{'EXIT',{system_limit,_}} = (catch id(1) bsl (1 bsl 69)),
+
+ %% There should be no system_limit exception when shifting a zero.
+ 0 = id(0) bsl (1 bsl 128),
+ 0 = id(0) bsr -(1 bsl 128),
+ Erlang = id(erlang),
+ 0 = Erlang:'bsl'(id(0), 1 bsl 128),
+ 0 = Erlang:'bsr'(id(0), -(1 bsl 128)),
ok.
maxbig() ->
@@ -449,3 +456,38 @@ my_bxor(A, B, N, Acc0) ->
false -> Acc0 bor (1 bsl N)
end,
my_bxor(A bsr 1, B bsr 1, N+1, Acc1).
+
+
+%% ERL-804
+band_2pow(_Config) ->
+ IL = lists:seq(8*3, 8*16, 4),
+ JL = lists:seq(0, 64),
+ [band_2pow_1((1 bsl I), (1 bsl J))
+ || I <- IL, J <- JL],
+ ok.
+
+band_2pow_1(A, B) ->
+ for(-1,1, fun(Ad) ->
+ for(-1,1, fun(Bd) ->
+ band_2pow_2(A+Ad, B+Bd),
+ band_2pow_2(-A+Ad, B+Bd),
+ band_2pow_2(A+Ad, -B+Bd),
+ band_2pow_2(-A+Ad, -B+Bd)
+ end)
+ end).
+
+band_2pow_2(A, B) ->
+ Correct = my_band(A, B),
+ case A band B of
+ Correct -> ok;
+ Wrong ->
+ io:format("~.16# band ~.16#\n", [A,B]),
+ io:format("Expected ~.16#\n", [Correct]),
+ io:format("Got ~.16#\n", [Wrong]),
+ ct:fail({failed, 'band'})
+
+ end.
+
+%% Implement band without band
+my_band(A, B) ->
+ bnot ((bnot A) bor (bnot B)).