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%%% -*- erlang-indent-level: 2 -*-
%%%-------------------------------------------------------------------
%%% File : basic_num_bif.erl
%%% Description : Taken from the compiler test suite
%%%-------------------------------------------------------------------
-module(basic_num_bif).
-export([test/0]).
%% Tests optimization of the BIFs:
%% abs/1
%% float/1
%% float_to_list/1
%% integer_to_list/1
%% list_to_float/1
%% list_to_integer/1
%% round/1
%% trunc/1
test() ->
Funs = [fun t_abs/0, fun t_float/0,
fun t_float_to_list/0, fun t_integer_to_list/0,
fun t_list_to_float_safe/0, fun t_list_to_float_risky/0,
fun t_list_to_integer/0, fun t_round/0, fun t_trunc/0],
lists:foreach(fun (F) -> ok = F() end, Funs).
t_abs() ->
%% Floats.
5.5 = abs(5.5),
0.0 = abs(0.0),
100.0 = abs(-100.0),
%% Integers.
5 = abs(5),
0 = abs(0),
100 = abs(-100),
%% The largest smallnum. OTP-3190.
X = (1 bsl 27) - 1,
X = abs(X),
X = abs(X-1)+1,
X = abs(X+1)-1,
X = abs(-X),
X = abs(-X-1)-1,
X = abs(-X+1)+1,
%% Bignums.
BigNum = 13984792374983749,
BigNum = abs(BigNum),
BigNum = abs(-BigNum),
ok.
t_float() ->
0.0 = float(0),
2.5 = float(2.5),
0.0 = float(0.0),
-100.55 = float(-100.55),
42.0 = float(42),
-100.0 = float(-100),
%% Bignums.
4294967305.0 = float(4294967305),
-4294967305.0 = float(-4294967305),
%% Extremely big bignums.
Big = list_to_integer(lists:duplicate(2000, $1)),
{'EXIT', {badarg, _}} = (catch float(Big)),
ok.
%% Tests float_to_list/1.
t_float_to_list() ->
test_ftl("0.0e+0", 0.0),
test_ftl("2.5e+1", 25.0),
test_ftl("2.5e+0", 2.5),
test_ftl("2.5e-1", 0.25),
test_ftl("-3.5e+17", -350.0e15),
ok.
test_ftl(Expect, Float) ->
%% No on the next line -- we want the line number from t_float_to_list.
Expect = remove_zeros(lists:reverse(float_to_list(Float)), []).
%% Removes any non-significant zeros in a floating point number.
%% Example: 2.500000e+01 -> 2.5e+1
remove_zeros([$+, $e|Rest], [$0, X|Result]) ->
remove_zeros([$+, $e|Rest], [X|Result]);
remove_zeros([$-, $e|Rest], [$0, X|Result]) ->
remove_zeros([$-, $e|Rest], [X|Result]);
remove_zeros([$0, $.|Rest], [$e|Result]) ->
remove_zeros(Rest, [$., $0, $e|Result]);
remove_zeros([$0|Rest], [$e|Result]) ->
remove_zeros(Rest, [$e|Result]);
remove_zeros([Char|Rest], Result) ->
remove_zeros(Rest, [Char|Result]);
remove_zeros([], Result) ->
Result.
%% Tests integer_to_list/1.
t_integer_to_list() ->
"0" = integer_to_list(0),
"42" = integer_to_list(42),
"-42" = integer_to_list(-42),
"-42" = integer_to_list(-42),
"32768" = integer_to_list(32768),
"268435455" = integer_to_list(268435455),
"-268435455" = integer_to_list(-268435455),
"123456932798748738738" = integer_to_list(123456932798748738738),
Big_List = lists:duplicate(2000, $1),
Big = list_to_integer(Big_List),
Big_List = integer_to_list(Big),
ok.
%% Tests list_to_float/1.
t_list_to_float_safe() ->
0.0 = list_to_float("0.0"),
0.0 = list_to_float("-0.0"),
0.5 = list_to_float("0.5"),
-0.5 = list_to_float("-0.5"),
100.0 = list_to_float("1.0e2"),
127.5 = list_to_float("127.5"),
-199.5 = list_to_float("-199.5"),
ok.
%% This might crash the emulator...
%% (Known to crash the Unix version of Erlang 4.4.1)
t_list_to_float_risky() ->
Many_Ones = lists:duplicate(25000, $1),
_ = list_to_float("2."++Many_Ones),
{'EXIT', {badarg, _}} = (catch list_to_float("2"++Many_Ones)),
ok.
%% Tests list_to_integer/1.
t_list_to_integer() ->
0 = list_to_integer("0"),
0 = list_to_integer("00"),
0 = list_to_integer("-0"),
1 = list_to_integer("1"),
-1 = list_to_integer("-1"),
42 = list_to_integer("42"),
-12 = list_to_integer("-12"),
32768 = list_to_integer("32768"),
268435455 = list_to_integer("268435455"),
-268435455 = list_to_integer("-268435455"),
%% Bignums.
123456932798748738738 = list_to_integer("123456932798748738738"),
_ = list_to_integer(lists:duplicate(2000, $1)),
ok.
%% Tests round/1.
t_round() ->
0 = round(0.0),
0 = round(0.4),
1 = round(0.5),
0 = round(-0.4),
-1 = round(-0.5),
255 = round(255.3),
256 = round(255.6),
-1033 = round(-1033.3),
-1034 = round(-1033.6),
%% OTP-3722:
X = (1 bsl 27) - 1,
MX = -X,
MXm1 = -X-1,
MXp1 = -X+1,
F = X + 0.0,
X = round(F),
X = round(F+1)-1,
X = round(F-1)+1,
MX = round(-F),
MXm1 = round(-F-1),
MXp1 = round(-F+1),
X = round(F+0.1),
X = round(F+1+0.1)-1,
X = round(F-1+0.1)+1,
MX = round(-F+0.1),
MXm1 = round(-F-1+0.1),
MXp1 = round(-F+1+0.1),
X = round(F-0.1),
X = round(F+1-0.1)-1,
X = round(F-1-0.1)+1,
MX = round(-F-0.1),
MXm1 = round(-F-1-0.1),
MXp1 = round(-F+1-0.1),
0.5 = abs(round(F+0.5)-(F+0.5)),
0.5 = abs(round(F-0.5)-(F-0.5)),
0.5 = abs(round(-F-0.5)-(-F-0.5)),
0.5 = abs(round(-F+0.5)-(-F+0.5)),
%% Bignums.
4294967296 = round(4294967296.1),
4294967297 = round(4294967296.9),
-4294967296 = -round(4294967296.1),
-4294967297 = -round(4294967296.9),
ok.
t_trunc() ->
0 = trunc(0.0),
5 = trunc(5.3333),
-10 = trunc(-10.978987),
%% The largest smallnum, converted to float (OTP-3722):
X = (1 bsl 27) - 1,
F = X + 0.0,
%% io:format("X = ~p/~w/~w, F = ~p/~w/~w, trunc(F) = ~p/~w/~w~n",
%% [X, X, binary_to_list(term_to_binary(X)),
%% F, F, binary_to_list(term_to_binary(F)),
%% trunc(F), trunc(F), binary_to_list(term_to_binary(trunc(F)))]),
X = trunc(F),
X = trunc(F+1)-1,
X = trunc(F-1)+1,
X = -trunc(-F),
X = -trunc(-F-1)-1,
X = -trunc(-F+1)+1,
%% Bignums.
4294967305 = trunc(4294967305.7),
-4294967305 = trunc(-4294967305.7),
ok.
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