diff options
Diffstat (limited to 'erts/emulator/test/big_SUITE.erl')
| -rw-r--r-- | erts/emulator/test/big_SUITE.erl | 57 |
1 files changed, 54 insertions, 3 deletions
diff --git a/erts/emulator/test/big_SUITE.erl b/erts/emulator/test/big_SUITE.erl index 0a42b09903..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() -> @@ -168,7 +168,11 @@ eval({op,_,Op,A0,B0}, LFH) -> Res = eval_op(Op, A, B), erlang:garbage_collect(), Res; -eval({integer,_,I}, _) -> I; +eval({integer,_,I}, _) -> + %% "Parasitic" ("symbiotic"?) test of squaring all numbers + %% found in the test data. + test_squaring(I), + I; eval({call,_,{atom,_,Local},Args0}, LFH) -> Args = eval_list(Args0, LFH), LFH(Local, Args). @@ -192,6 +196,18 @@ eval_op('bxor', A, B) -> A bxor B; eval_op('bsl', A, B) -> A bsl B; eval_op('bsr', A, B) -> A bsr B. +test_squaring(I) -> + %% Multiplying an integer by itself is specially optimized, so we + %% should take special care to test squaring. The optimization + %% will kick in when the two operands have the same address. + Sqr = I * I, + + %% This expression will be multiplied in the usual way, because + %% the the two operands for '*' are stored at different addresses. + Sqr = I * ((I + id(1)) - id(1)), + + ok. + %% Built in test functions fac(0) -> 1; @@ -456,3 +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)). |