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Diffstat (limited to 'm4/ax_cc_maxopt.m4')
| -rw-r--r-- | m4/ax_cc_maxopt.m4 | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/m4/ax_cc_maxopt.m4 b/m4/ax_cc_maxopt.m4 new file mode 100644 index 0000000..7c80bff --- /dev/null +++ b/m4/ax_cc_maxopt.m4 @@ -0,0 +1,180 @@ +# =========================================================================== +# http://autoconf-archive.cryp.to/ax_cc_maxopt.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_CC_MAXOPT +# +# DESCRIPTION +# +# Try to turn on "good" C optimization flags for various compilers and +# architectures, for some definition of "good". (In our case, good for +# FFTW and hopefully for other scientific codes. Modify as needed.) +# +# The user can override the flags by setting the CFLAGS environment +# variable. The user can also specify --enable-portable-binary in order to +# disable any optimization flags that might result in a binary that only +# runs on the host architecture. +# +# Note also that the flags assume that ANSI C aliasing rules are followed +# by the code (e.g. for gcc's -fstrict-aliasing), and that floating-point +# computations can be re-ordered as needed. +# +# Requires macros: AX_CHECK_COMPILER_FLAGS, AX_COMPILER_VENDOR, +# AX_GCC_ARCHFLAG, AX_GCC_X86_CPUID. +# +# LICENSE +# +# Copyright (c) 2008 Steven G. Johnson <stevenj@alum.mit.edu> +# Copyright (c) 2008 Matteo Frigo +# +# 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 <http://www.gnu.org/licenses/>. +# +# 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. + +AC_DEFUN([AX_CC_MAXOPT], +[ +AC_REQUIRE([AC_PROG_CC]) +AC_REQUIRE([AX_COMPILER_VENDOR]) +AC_REQUIRE([AC_CANONICAL_HOST]) + +AC_ARG_ENABLE(portable-binary, [AC_HELP_STRING([--enable-portable-binary], [disable compiler optimizations that would produce unportable binaries])], + acx_maxopt_portable=$withval, acx_maxopt_portable=no) + +# Try to determine "good" native compiler flags if none specified via CFLAGS +if test "$ac_test_CFLAGS" != "set"; then + CFLAGS="" + case $ax_cv_c_compiler_vendor in + dec) CFLAGS="-newc -w0 -O5 -ansi_alias -ansi_args -fp_reorder -tune host" + if test "x$acx_maxopt_portable" = xno; then + CFLAGS="$CFLAGS -arch host" + fi;; + + sun) CFLAGS="-native -fast -xO5 -dalign" + if test "x$acx_maxopt_portable" = xyes; then + CFLAGS="$CFLAGS -xarch=generic" + fi;; + + hp) CFLAGS="+Oall +Optrs_ansi +DSnative" + if test "x$acx_maxopt_portable" = xyes; then + CFLAGS="$CFLAGS +DAportable" + fi;; + + ibm) if test "x$acx_maxopt_portable" = xno; then + xlc_opt="-qarch=auto -qtune=auto" + else + xlc_opt="-qtune=auto" + fi + AX_CHECK_COMPILER_FLAGS($xlc_opt, + CFLAGS="-O3 -qansialias -w $xlc_opt", + [CFLAGS="-O3 -qansialias -w" + echo "******************************************************" + echo "* You seem to have the IBM C compiler. It is *" + echo "* recommended for best performance that you use: *" + echo "* *" + echo "* CFLAGS=-O3 -qarch=xxx -qtune=xxx -qansialias -w *" + echo "* ^^^ ^^^ *" + echo "* where xxx is pwr2, pwr3, 604, or whatever kind of *" + echo "* CPU you have. (Set the CFLAGS environment var. *" + echo "* and re-run configure.) For more info, man cc. *" + echo "******************************************************"]) + ;; + + intel) CFLAGS="-O3 -ansi_alias" + if test "x$acx_maxopt_portable" = xno; then + icc_archflag=unknown + icc_flags="" + case $host_cpu in + i686*|x86_64*) + # icc accepts gcc assembly syntax, so these should work: + AX_GCC_X86_CPUID(0) + AX_GCC_X86_CPUID(1) + case $ax_cv_gcc_x86_cpuid_0 in # see AX_GCC_ARCHFLAG + *:756e6547:*:*) # Intel + case $ax_cv_gcc_x86_cpuid_1 in + *6a?:*[[234]]:*:*|*6[[789b]]?:*:*:*) icc_flags="-xK";; + *f3[[347]]:*:*:*|*f4[1347]:*:*:*) icc_flags="-xP -xN -xW -xK";; + *f??:*:*:*) icc_flags="-xN -xW -xK";; + esac ;; + esac ;; + esac + if test "x$icc_flags" != x; then + for flag in $icc_flags; do + AX_CHECK_COMPILER_FLAGS($flag, [icc_archflag=$flag; break]) + done + fi + AC_MSG_CHECKING([for icc architecture flag]) + AC_MSG_RESULT($icc_archflag) + if test "x$icc_archflag" != xunknown; then + CFLAGS="$CFLAGS $icc_archflag" + fi + fi + ;; + + gnu) + # default optimization flags for gcc on all systems + # 2009-07-30 JB Langston + # removed -fomit-frame-pointer due to incompatibility with SFFE + CFLAGS="-O3" + + # -malign-double for x86 systems + AX_CHECK_COMPILER_FLAGS(-malign-double, CFLAGS="$CFLAGS -malign-double") + + # -fstrict-aliasing for gcc-2.95+ + AX_CHECK_COMPILER_FLAGS(-fstrict-aliasing, + CFLAGS="$CFLAGS -fstrict-aliasing") + + # note that we enable "unsafe" fp optimization with other compilers, too + AX_CHECK_COMPILER_FLAGS(-ffast-math, CFLAGS="$CFLAGS -ffast-math") + + AX_GCC_ARCHFLAG($acx_maxopt_portable) + ;; + esac + + if test -z "$CFLAGS"; then + echo "" + echo "********************************************************" + echo "* WARNING: Don't know the best CFLAGS for this system *" + echo "* Use ./configure CFLAGS=... to specify your own flags *" + echo "* (otherwise, a default of CFLAGS=-O3 will be used) *" + echo "********************************************************" + echo "" + CFLAGS="-O3" + fi + + AX_CHECK_COMPILER_FLAGS($CFLAGS, [], [ + echo "" + echo "********************************************************" + echo "* WARNING: The guessed CFLAGS don't seem to work with *" + echo "* your compiler. *" + echo "* Use ./configure CFLAGS=... to specify your own flags *" + echo "********************************************************" + echo "" + CFLAGS="" + ]) + +fi +]) |