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author | Ralph Giles <giles@thaumas.net> | 2014-11-04 11:57:28 -0800 |
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committer | Erik de Castro Lopo <erikd@mega-nerd.com> | 2014-11-04 21:18:48 -0800 |
commit | 1f30b3e7117bb41fbb9dc61fb345f1321f9e0330 (patch) | |
tree | e34a211118b973024e687d517e8f56a4d28a149a /m4 | |
parent | e0fbe7193569badcbcd72f33fd39e9e31b55ecf0 (diff) | |
download | flac-1f30b3e7117bb41fbb9dc61fb345f1321f9e0330.tar.gz |
Add autoconf macro to check for the bswap16 intrinsic.
Signed-off-by: Erik de Castro Lopo <erikd@mega-nerd.com>
Diffstat (limited to 'm4')
-rw-r--r-- | m4/bswap.m4 | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/m4/bswap.m4 b/m4/bswap.m4 index 926f820e..72af3333 100644 --- a/m4/bswap.m4 +++ b/m4/bswap.m4 @@ -1,4 +1,4 @@ -dnl Copyright (C) 2012 Xiph.org Foundation +dnl Copyright (C) 2012-2014 Xiph.org Foundation dnl dnl Redistribution and use in source and binary forms, with or without dnl modification, are permitted provided that the following conditions @@ -53,3 +53,30 @@ AC_DEFUN([XIPH_C_BSWAP32], )] )# XIPH_C_BSWAP32 + + +dnl @synopsis XIPH_C_BSWAP16 +dnl +dnl @author Erik de Castro Lopo <erikd@mega-nerd.com> +dnl +dnl Dtermine whether the compiler has the __builtin_bswap16() intrinsic which +dnl is likely to be present for most versions of GCC as well as Clang. + +AC_DEFUN([XIPH_C_BSWAP16], +[AC_CACHE_CHECK(for bswap16 instrinsic, + ac_cv_c_bswap16, + + # Initialize to no + ac_cv_c_bswap16=no + HAVE_BSWAP16=0 + + [AC_TRY_LINK([], + return __builtin_bswap16 (0) ;, + ac_cv_c_bswap16=yes + HAVE_BSWAP16=1 + )] + AC_DEFINE_UNQUOTED(HAVE_BSWAP16, ${HAVE_BSWAP16}, + [Compiler has the __builtin_bswap16 intrinsic]) + + )] +)# XIPH_C_BSWAP16 |