diff options
Diffstat (limited to 'erts/emulator/test')
| -rw-r--r-- | erts/emulator/test/big_SUITE.erl | 39 |
1 files changed, 37 insertions, 2 deletions
diff --git a/erts/emulator/test/big_SUITE.erl b/erts/emulator/test/big_SUITE.erl index 5b602dd4dc..3b9b9e5989 100644 --- a/erts/emulator/test/big_SUITE.erl +++ b/erts/emulator/test/big_SUITE.erl @@ -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() -> @@ -472,3 +472,38 @@ 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)). |