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Diffstat (limited to 'sysdeps/x86_64/bits/byteswap-16.h')
-rw-r--r--sysdeps/x86_64/bits/byteswap-16.h49
1 files changed, 49 insertions, 0 deletions
diff --git a/sysdeps/x86_64/bits/byteswap-16.h b/sysdeps/x86_64/bits/byteswap-16.h
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--- /dev/null
+++ b/sysdeps/x86_64/bits/byteswap-16.h
@@ -0,0 +1,49 @@
+/* Macros to swap the order of bytes in 16-bit integer values.
+ Copyright (C) 2012 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+
+ The GNU C Library is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Lesser General Public
+ License as published by the Free Software Foundation; either
+ version 2.1 of the License, or (at your option) any later version.
+
+ The GNU C Library 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with the GNU C Library; if not, see
+ <http://www.gnu.org/licenses/>. */
+
+#ifndef _BITS_BYTESWAP_H
+# error "Never use <bits/byteswap-16.h> directly; include <byteswap.h> instead."
+#endif
+
+#ifdef __GNUC__
+# if __GNUC__ >= 2
+# define __bswap_16(x) \
+ (__extension__ \
+ ({ register unsigned short int __v, __x = (unsigned short int) (x); \
+ if (__builtin_constant_p (__x)) \
+ __v = __bswap_constant_16 (__x); \
+ else \
+ __asm__ ("rorw $8, %w0" \
+ : "=r" (__v) \
+ : "0" (__x) \
+ : "cc"); \
+ __v; }))
+# else
+/* This is better than nothing. */
+# define __bswap_16(x) \
+ (__extension__ \
+ ({ register unsigned short int __x = (unsigned short int) (x); \
+ __bswap_constant_16 (__x); }))
+# endif
+#else
+static __inline unsigned short int
+__bswap_16 (unsigned short int __bsx)
+{
+ return __bswap_constant_16 (__bsx);
+}
+#endif