From e3f4cd83939f28e17addac889208985196d22f22 Mon Sep 17 00:00:00 2001 From: Lukas Larsson Date: Wed, 5 Nov 2014 11:18:05 +0100 Subject: erts: Use finite instead of isfinite with gcc Turns out that isfinite emits a function call and not an instruction in gcc, this makes estone float arith about 50-75% slower. finite emits the instruction so we use that instead. --- erts/emulator/sys/unix/erl_unix_sys.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'erts/emulator/sys') diff --git a/erts/emulator/sys/unix/erl_unix_sys.h b/erts/emulator/sys/unix/erl_unix_sys.h index c3dba69acb..f7a6298d5b 100644 --- a/erts/emulator/sys/unix/erl_unix_sys.h +++ b/erts/emulator/sys/unix/erl_unix_sys.h @@ -229,6 +229,17 @@ extern void sys_stop_cat(void); #ifdef USE_ISINF_ISNAN /* simulate finite() */ # define isfinite(f) (!isinf(f) && !isnan(f)) # define HAVE_ISFINITE +#elif defined(__GNUC__) && defined(HAVE_FINITE) +/* We use finite in gcc as it emits assembler instead of + the function call that isfinite emits. The assembler is + significantly faster. */ +# ifdef isfinite +# undef isfinite +# endif +# define isfinite finite +# ifndef HAVE_ISFINITE +# define HAVE_ISFINITE +# endif #elif defined(isfinite) && !defined(HAVE_ISFINITE) # define HAVE_ISFINITE #elif !defined(HAVE_ISFINITE) && defined(HAVE_FINITE) -- cgit v1.2.3