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| author | Erlang/OTP <[email protected]> | 2018-12-20 13:26:55 +0100 |
|---|---|---|
| committer | Erlang/OTP <[email protected]> | 2018-12-20 13:26:55 +0100 |
| commit | 902f5bbc786b28f496d5e01f96ca2ef8426f66b3 (patch) | |
| tree | a6c24a4b2f74a18aa49e8b72af2c9de29e8f1eaa /erts | |
| parent | 5d2a5f23ed1251e487eab53ee19f8cbb56f7e22d (diff) | |
| parent | c8d3bff46adbff3205eaf76de8a634557cbd4af4 (diff) | |
| download | otp-902f5bbc786b28f496d5e01f96ca2ef8426f66b3.tar.gz otp-902f5bbc786b28f496d5e01f96ca2ef8426f66b3.tar.bz2 otp-902f5bbc786b28f496d5e01f96ca2ef8426f66b3.zip | |
Merge branch 'sverker/big-band-bug/ERL-804/OTP-15487' into maint-21
* sverker/big-band-bug/ERL-804/OTP-15487:
erts: Fix bug in 'band' of two negative numbers, one big
Diffstat (limited to 'erts')
| -rw-r--r-- | erts/emulator/beam/big.c | 7 | ||||
| -rw-r--r-- | erts/emulator/test/big_SUITE.erl | 39 |
2 files changed, 42 insertions, 4 deletions
diff --git a/erts/emulator/beam/big.c b/erts/emulator/beam/big.c index 84338769e0..b373d3a577 100644 --- a/erts/emulator/beam/big.c +++ b/erts/emulator/beam/big.c @@ -1159,8 +1159,11 @@ static dsize_t I_band(ErtsDigit* x, dsize_t xl, short xsgn, *r++ = ~c1 & ~c2; x++; y++; } - while(xl--) - *r++ = ~*x++; + while(xl--) { + DSUBb(*x,0,b1,c1); + *r++ = ~c1; + x++; + } } } return I_btrail(r0, r, sign); diff --git a/erts/emulator/test/big_SUITE.erl b/erts/emulator/test/big_SUITE.erl index 0a42b09903..29508ffc7c 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() -> @@ -456,3 +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)). |