From 2c3066e5da54659f19799005eddb1d134c6d0166 Mon Sep 17 00:00:00 2001 From: Vadim Yanitskiy Date: Sun, 30 Apr 2017 19:41:56 +0700 Subject: configure.ac: add SIMD detection capabilities This change adds a check whether compiler supports some SIMD (Single Instruction, Multiple Data) instructions. It is enabled by default, and can be disabled by configure option --disable-simd. The check macro is based on the AX_EXT from autoconf-archive: www.gnu.org/software/autoconf-archive/ax_ext.html And depends on the ax_check_compile_flag macro: www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html Currently only the following SIMD extensions are being checked: AVX2, SSE3, SSE4.1, but adding others is also possible. All found extensions are being defined in the 'config.h' header. Change-Id: Idf8fff984bd936a75c7c307338df88ba4b005817 --- m4/ax_check_compile_flag.m4 | 74 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) create mode 100644 m4/ax_check_compile_flag.m4 (limited to 'm4/ax_check_compile_flag.m4') diff --git a/m4/ax_check_compile_flag.m4 b/m4/ax_check_compile_flag.m4 new file mode 100644 index 00000000..dcabb92a --- /dev/null +++ b/m4/ax_check_compile_flag.m4 @@ -0,0 +1,74 @@ +# =========================================================================== +# https://www.gnu.org/software/autoconf-archive/ax_check_compile_flag.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_CHECK_COMPILE_FLAG(FLAG, [ACTION-SUCCESS], [ACTION-FAILURE], [EXTRA-FLAGS], [INPUT]) +# +# DESCRIPTION +# +# Check whether the given FLAG works with the current language's compiler +# or gives an error. (Warnings, however, are ignored) +# +# ACTION-SUCCESS/ACTION-FAILURE are shell commands to execute on +# success/failure. +# +# If EXTRA-FLAGS is defined, it is added to the current language's default +# flags (e.g. CFLAGS) when the check is done. The check is thus made with +# the flags: "CFLAGS EXTRA-FLAGS FLAG". This can for example be used to +# force the compiler to issue an error when a bad flag is given. +# +# INPUT gives an alternative input source to AC_COMPILE_IFELSE. +# +# NOTE: Implementation based on AX_CFLAGS_GCC_OPTION. Please keep this +# macro in sync with AX_CHECK_{PREPROC,LINK}_FLAG. +# +# LICENSE +# +# Copyright (c) 2008 Guido U. Draheim +# Copyright (c) 2011 Maarten Bosmans +# +# This program is free software: you can redistribute it and/or modify it +# under the terms of the GNU General Public License as published by the +# Free Software Foundation, either version 3 of the License, or (at your +# option) any later version. +# +# This program is distributed in the hope that it will be useful, but +# WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General +# Public License for more details. +# +# You should have received a copy of the GNU General Public License along +# with this program. If not, see . +# +# As a special exception, the respective Autoconf Macro's copyright owner +# gives unlimited permission to copy, distribute and modify the configure +# scripts that are the output of Autoconf when processing the Macro. You +# need not follow the terms of the GNU General Public License when using +# or distributing such scripts, even though portions of the text of the +# Macro appear in them. The GNU General Public License (GPL) does govern +# all other use of the material that constitutes the Autoconf Macro. +# +# This special exception to the GPL applies to versions of the Autoconf +# Macro released by the Autoconf Archive. When you make and distribute a +# modified version of the Autoconf Macro, you may extend this special +# exception to the GPL to apply to your modified version as well. + +#serial 5 + +AC_DEFUN([AX_CHECK_COMPILE_FLAG], +[AC_PREREQ(2.64)dnl for _AC_LANG_PREFIX and AS_VAR_IF +AS_VAR_PUSHDEF([CACHEVAR],[ax_cv_check_[]_AC_LANG_ABBREV[]flags_$4_$1])dnl +AC_CACHE_CHECK([whether _AC_LANG compiler accepts $1], CACHEVAR, [ + ax_check_save_flags=$[]_AC_LANG_PREFIX[]FLAGS + _AC_LANG_PREFIX[]FLAGS="$[]_AC_LANG_PREFIX[]FLAGS $4 $1" + AC_COMPILE_IFELSE([m4_default([$5],[AC_LANG_PROGRAM()])], + [AS_VAR_SET(CACHEVAR,[yes])], + [AS_VAR_SET(CACHEVAR,[no])]) + _AC_LANG_PREFIX[]FLAGS=$ax_check_save_flags]) +AS_VAR_IF(CACHEVAR,yes, + [m4_default([$2], :)], + [m4_default([$3], :)]) +AS_VAR_POPDEF([CACHEVAR])dnl +])dnl AX_CHECK_COMPILE_FLAGS -- cgit v1.2.3