diff options
Diffstat (limited to 'erts/emulator/test/big_SUITE.erl')
| -rw-r--r-- | erts/emulator/test/big_SUITE.erl | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/erts/emulator/test/big_SUITE.erl b/erts/emulator/test/big_SUITE.erl index 3193d56e2a..c5bb228bc3 100644 --- a/erts/emulator/test/big_SUITE.erl +++ b/erts/emulator/test/big_SUITE.erl @@ -23,6 +23,7 @@ init_per_group/2,end_per_group/2]). -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, shift_limit_1/1, powmod/1, system_limit/1, toobig/1, otp_6692/1]). %% Internal exports. @@ -40,6 +41,7 @@ suite() -> [{ct_hooks,[ts_install_cth]}]. all() -> [t_div, eq_28, eq_32, eq_big, eq_math, big_literals, borders, negative, {group, big_float}, shift_limit_1, + bxor_2pow, powmod, system_limit, toobig, otp_6692]. groups() -> @@ -423,3 +425,54 @@ loop2(X,Y,N,M) -> end, loop2(X,Y,N+1,M). + +%% ERL-450 +bxor_2pow(_Config) -> + IL = lists:seq(8*3, 8*16, 4), + JL = lists:seq(0, 64), + [bxor_2pow_1((1 bsl I), (1 bsl J)) + || I <- IL, J <- JL], + ok. + +bxor_2pow_1(A, B) -> + for(-1,1, fun(Ad) -> + for(-1,1, fun(Bd) -> + bxor_2pow_2(A+Ad, B+Bd), + bxor_2pow_2(-A+Ad, B+Bd), + bxor_2pow_2(A+Ad, -B+Bd), + bxor_2pow_2(-A+Ad, -B+Bd) + end) + end). + +for(From, To, _Fun) when From > To -> + ok; +for(From, To, Fun) -> + Fun(From), + for(From+1, To, Fun). + +bxor_2pow_2(A, B) -> + Correct = my_bxor(A, B), + case A bxor B of + Correct -> ok; + Wrong -> + io:format("~.16b bxor ~.16b\n", [A,B]), + io:format("Expected ~.16b\n", [Correct]), + io:format("Got ~.16b\n", [Wrong]), + ct:fail({failed, 'bxor'}) + + end. + +%% Implement bxor without bxor +my_bxor(A, B) -> + my_bxor(A, B, 0, 0). + +my_bxor(0, 0, _, Acc) -> Acc; +my_bxor(-1, -1, _, Acc) -> Acc; +my_bxor(-1, 0, N, Acc) -> (-1 bsl N) bor Acc; % sign extension +my_bxor(0, -1, N, Acc) -> (-1 bsl N) bor Acc; % sign extension +my_bxor(A, B, N, Acc0) -> + Acc1 = case (A band 1) =:= (B band 1) of + true -> Acc0; + false -> Acc0 bor (1 bsl N) + end, + my_bxor(A bsr 1, B bsr 1, N+1, Acc1). |