diff options
Diffstat (limited to 'erts')
| -rw-r--r-- | erts/configure.in | 5 | ||||
| -rw-r--r-- | erts/emulator/beam/bif.tab | 1 | ||||
| -rw-r--r-- | erts/emulator/beam/erl_math.c | 18 |
3 files changed, 24 insertions, 0 deletions
diff --git a/erts/configure.in b/erts/configure.in index 1676d3d216..6bea197a80 100644 --- a/erts/configure.in +++ b/erts/configure.in @@ -4905,6 +4905,11 @@ LDFLAGS="$LDFLAGS $sanitizers" ]) dnl ---------------------------------------------------------------------- +dnl Check for log2 +dnl ---------------------------------------------------------------------- +AC_CHECK_FUNCS([log2]) + +dnl ---------------------------------------------------------------------- dnl Output the result. dnl ---------------------------------------------------------------------- diff --git a/erts/emulator/beam/bif.tab b/erts/emulator/beam/bif.tab index aea3224342..1d0d214e77 100644 --- a/erts/emulator/beam/bif.tab +++ b/erts/emulator/beam/bif.tab @@ -194,6 +194,7 @@ bif math:erf/1 bif math:erfc/1 bif math:exp/1 bif math:log/1 +bif math:log2/1 bif math:log10/1 bif math:sqrt/1 bif math:atan2/2 diff --git a/erts/emulator/beam/erl_math.c b/erts/emulator/beam/erl_math.c index 16d4fdc09c..9b864628db 100644 --- a/erts/emulator/beam/erl_math.c +++ b/erts/emulator/beam/erl_math.c @@ -207,6 +207,24 @@ BIF_RETTYPE math_log_1(BIF_ALIST_1) return math_call_1(BIF_P, log, BIF_ARG_1); } +#ifdef HAVE_LOG2 +static double +log2_wrapper(double x) +{ + return log2(x); +} +#else +static double +log2_wrapper(double x) +{ + return log(x) / 0.6931471805599453; /* log(2.0); */ +} +#endif + +BIF_RETTYPE math_log2_1(BIF_ALIST_1) +{ + return math_call_1(BIF_P, log2_wrapper, BIF_ARG_1); +} BIF_RETTYPE math_log10_1(BIF_ALIST_1) { |