summaryrefslogtreecommitdiff
path: root/m4/ax_gcc_builtin.m4
diff options
context:
space:
mode:
Diffstat (limited to 'm4/ax_gcc_builtin.m4')
-rw-r--r--m4/ax_gcc_builtin.m4168
1 files changed, 168 insertions, 0 deletions
diff --git a/m4/ax_gcc_builtin.m4 b/m4/ax_gcc_builtin.m4
new file mode 100644
index 00000000000..b28a91b14a5
--- /dev/null
+++ b/m4/ax_gcc_builtin.m4
@@ -0,0 +1,168 @@
+# ===========================================================================
+# 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_<BUILTIN>. Keep in mind that since
+# builtins usually start with two underscores they will be copied over
+# into the HAVE_<BUILTIN> definition (e.g. HAVE___BUILTIN_EXPECT for
+# __builtin_expect()).
+#
+# The macro caches its result in the ax_cv_have_<BUILTIN> variable (e.g.
+# ax_cv_have___builtin_expect).
+#
+# The macro currently supports the following built-in functions:
+#
+# __builtin_assume_aligned
+# __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 <gabriele.svelto@gmail.com>
+#
+# 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 2
+
+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_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])
+])