From 83a9cd5258fbd1acf293734cb4c3aba0f9ffcc9b Mon Sep 17 00:00:00 2001 From: "Bryn M. Reeves" Date: Mon, 12 Dec 2016 12:03:16 +0000 Subject: [PATCH] configure: check for __builtin_clz() --- aclocal.m4 | 171 +++++++++++++++++++++++++++++++++++++++++ configure | 44 +++++++++++ configure.in | 1 + include/configure.h.in | 3 + 4 files changed, 219 insertions(+) diff --git a/aclocal.m4 b/aclocal.m4 index 35107ac50..1f02c2bed 100644 --- a/aclocal.m4 +++ b/aclocal.m4 @@ -536,4 +536,175 @@ AC_DEFUN([AM_RUN_LOG], echo "$as_me:$LINENO: \$? = $ac_status" >&AS_MESSAGE_LOG_FD (exit $ac_status); }]) +# =========================================================================== +# http://www.gnu.org/software/autoconf-archive/ax_gcc_builtin.html +# =========================================================================== +# +# SYNOPSIS +# +# AX_GCC_BUILTIN(BUILTIN) +# +# DESCRIPTION +# +# This macro checks if the compiler supports one of GCC's built-in +# functions; many other compilers also provide those same built-ins. +# +# The BUILTIN parameter is the name of the built-in function. +# +# If BUILTIN is supported define HAVE_. Keep in mind that since +# builtins usually start with two underscores they will be copied over +# into the HAVE_ definition (e.g. HAVE___BUILTIN_EXPECT for +# __builtin_expect()). +# +# The macro caches its result in the ax_cv_have_ variable (e.g. +# ax_cv_have___builtin_expect). +# +# The macro currently supports the following built-in functions: +# +# __builtin_assume_aligned +# __builtin_bswap16 +# __builtin_bswap32 +# __builtin_bswap64 +# __builtin_choose_expr +# __builtin___clear_cache +# __builtin_clrsb +# __builtin_clrsbl +# __builtin_clrsbll +# __builtin_clz +# __builtin_clzl +# __builtin_clzll +# __builtin_complex +# __builtin_constant_p +# __builtin_ctz +# __builtin_ctzl +# __builtin_ctzll +# __builtin_expect +# __builtin_ffs +# __builtin_ffsl +# __builtin_ffsll +# __builtin_fpclassify +# __builtin_huge_val +# __builtin_huge_valf +# __builtin_huge_vall +# __builtin_inf +# __builtin_infd128 +# __builtin_infd32 +# __builtin_infd64 +# __builtin_inff +# __builtin_infl +# __builtin_isinf_sign +# __builtin_nan +# __builtin_nand128 +# __builtin_nand32 +# __builtin_nand64 +# __builtin_nanf +# __builtin_nanl +# __builtin_nans +# __builtin_nansf +# __builtin_nansl +# __builtin_object_size +# __builtin_parity +# __builtin_parityl +# __builtin_parityll +# __builtin_popcount +# __builtin_popcountl +# __builtin_popcountll +# __builtin_powi +# __builtin_powif +# __builtin_powil +# __builtin_prefetch +# __builtin_trap +# __builtin_types_compatible_p +# __builtin_unreachable +# +# Unsuppored built-ins will be tested with an empty parameter set and the +# result of the check might be wrong or meaningless so use with care. +# +# LICENSE +# +# Copyright (c) 2013 Gabriele Svelto +# +# Copying and distribution of this file, with or without modification, are +# permitted in any medium without royalty provided the copyright notice +# and this notice are preserved. This file is offered as-is, without any +# warranty. + +#serial 3 + +AC_DEFUN([AX_GCC_BUILTIN], [ + AS_VAR_PUSHDEF([ac_var], [ax_cv_have_$1]) + + AC_CACHE_CHECK([for $1], [ac_var], [ + AC_LINK_IFELSE([AC_LANG_PROGRAM([], [ + m4_case([$1], + [__builtin_assume_aligned], [$1("", 0)], + [__builtin_bswap16], [$1(0)], + [__builtin_bswap32], [$1(0)], + [__builtin_bswap64], [$1(0)], + [__builtin_choose_expr], [$1(0, 0, 0)], + [__builtin___clear_cache], [$1("", "")], + [__builtin_clrsb], [$1(0)], + [__builtin_clrsbl], [$1(0)], + [__builtin_clrsbll], [$1(0)], + [__builtin_clz], [$1(0)], + [__builtin_clzl], [$1(0)], + [__builtin_clzll], [$1(0)], + [__builtin_complex], [$1(0.0, 0.0)], + [__builtin_constant_p], [$1(0)], + [__builtin_ctz], [$1(0)], + [__builtin_ctzl], [$1(0)], + [__builtin_ctzll], [$1(0)], + [__builtin_expect], [$1(0, 0)], + [__builtin_ffs], [$1(0)], + [__builtin_ffsl], [$1(0)], + [__builtin_ffsll], [$1(0)], + [__builtin_fpclassify], [$1(0, 1, 2, 3, 4, 0.0)], + [__builtin_huge_val], [$1()], + [__builtin_huge_valf], [$1()], + [__builtin_huge_vall], [$1()], + [__builtin_inf], [$1()], + [__builtin_infd128], [$1()], + [__builtin_infd32], [$1()], + [__builtin_infd64], [$1()], + [__builtin_inff], [$1()], + [__builtin_infl], [$1()], + [__builtin_isinf_sign], [$1(0.0)], + [__builtin_nan], [$1("")], + [__builtin_nand128], [$1("")], + [__builtin_nand32], [$1("")], + [__builtin_nand64], [$1("")], + [__builtin_nanf], [$1("")], + [__builtin_nanl], [$1("")], + [__builtin_nans], [$1("")], + [__builtin_nansf], [$1("")], + [__builtin_nansl], [$1("")], + [__builtin_object_size], [$1("", 0)], + [__builtin_parity], [$1(0)], + [__builtin_parityl], [$1(0)], + [__builtin_parityll], [$1(0)], + [__builtin_popcount], [$1(0)], + [__builtin_popcountl], [$1(0)], + [__builtin_popcountll], [$1(0)], + [__builtin_powi], [$1(0, 0)], + [__builtin_powif], [$1(0, 0)], + [__builtin_powil], [$1(0, 0)], + [__builtin_prefetch], [$1("")], + [__builtin_trap], [$1()], + [__builtin_types_compatible_p], [$1(int, int)], + [__builtin_unreachable], [$1()], + [m4_warn([syntax], [Unsupported built-in $1, the test may fail]) + $1()] + ) + ])], + [AS_VAR_SET([ac_var], [yes])], + [AS_VAR_SET([ac_var], [no])]) + ]) + + AS_IF([test yes = AS_VAR_GET([ac_var])], + [AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_$1), 1, + [Define to 1 if the system has the `$1' built-in function])], []) + + AS_VAR_POPDEF([ac_var]) +]) + m4_include([acinclude.m4]) diff --git a/configure b/configure index c82a19bcb..1cb4b541a 100755 --- a/configure +++ b/configure @@ -6321,6 +6321,50 @@ _ACEOF esac + + + { $as_echo "$as_me:${as_lineno-$LINENO}: checking for __builtin_clz" >&5 +$as_echo_n "checking for __builtin_clz... " >&6; } +if ${ax_cv_have___builtin_clz+:} false; then : + $as_echo_n "(cached) " >&6 +else + + cat confdefs.h - <<_ACEOF >conftest.$ac_ext +/* end confdefs.h. */ + +int +main () +{ + + __builtin_clz(0) + + ; + return 0; +} +_ACEOF +if ac_fn_c_try_link "$LINENO"; then : + ax_cv_have___builtin_clz=yes +else + ax_cv_have___builtin_clz=no +fi +rm -f core conftest.err conftest.$ac_objext \ + conftest$ac_exeext conftest.$ac_ext + +fi +{ $as_echo "$as_me:${as_lineno-$LINENO}: result: $ax_cv_have___builtin_clz" >&5 +$as_echo "$ax_cv_have___builtin_clz" >&6; } + + if test yes = $ax_cv_have___builtin_clz; then : + +cat >>confdefs.h <<_ACEOF +#define HAVE___BUILTIN_CLZ 1 +_ACEOF + +fi + + + + ################################################################################ for ac_func in ftruncate gethostname getpagesize gettimeofday localtime_r \ memchr memset mkdir mkfifo munmap nl_langinfo realpath rmdir setenv \ diff --git a/configure.in b/configure.in index cc77aaba9..8ec65c8c6 100644 --- a/configure.in +++ b/configure.in @@ -134,6 +134,7 @@ AC_TYPE_UINT8_T AC_TYPE_UINT16_T AC_TYPE_UINT32_T AC_TYPE_UINT64_T +AX_GCC_BUILTIN([__builtin_clz]) ################################################################################ dnl -- Check for functions diff --git a/include/configure.h.in b/include/configure.h.in index 3c43bd529..cf8dc9450 100644 --- a/include/configure.h.in +++ b/include/configure.h.in @@ -341,6 +341,9 @@ /* Define to 1 if the system has the type `ptrdiff_t'. */ #undef HAVE_PTRDIFF_T +/* Define to 1 if the compiler has the `__builtin_clz` builtin. */ +#undef HAVE___BUILTIN_CLZ + /* Define to 1 if you have the header file. */ #undef HAVE_READLINE_HISTORY_H