about summary refs log tree commit diff
path: root/sysdeps/s390/bits/byteswap-16.h
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/s390/bits/byteswap-16.h')
-rw-r--r--sysdeps/s390/bits/byteswap-16.h65
1 files changed, 65 insertions, 0 deletions
diff --git a/sysdeps/s390/bits/byteswap-16.h b/sysdeps/s390/bits/byteswap-16.h
new file mode 100644
index 0000000000..8bfec78ffe
--- /dev/null
+++ b/sysdeps/s390/bits/byteswap-16.h
@@ -0,0 +1,65 @@
+/* Macros to swap the order of bytes in 16-bit integer values.  s390 version
+   Copyright (C) 2012 Free Software Foundation, Inc.
+   Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com).
+   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
+
+#include <bits/wordsize.h>
+
+/* Swap bytes in 16 bit value. */
+#if defined __GNUC__ && __GNUC__ >= 2
+# if __WORDSIZE == 64
+#  define __bswap_16(x) \
+     (__extension__							      \
+      ({ unsigned short int __v, __x = (x);				      \
+	 if (__builtin_constant_p (x))					      \
+	   __v = __bswap_constant_16 (__x);				      \
+	 else {								      \
+	   unsigned short int __tmp = (unsigned short int) (__x);             \
+	   __asm__ __volatile__ (                                             \
+	      "lrvh %0,%1"                                                    \
+	      : "=&d" (__v) : "m" (__tmp) );                                  \
+	 }                                                                    \
+	 __v; }))
+# else
+#  define __bswap_16(x) \
+     (__extension__							      \
+      ({ unsigned short int __v, __x = (x);				      \
+	 if (__builtin_constant_p (x))					      \
+	   __v = __bswap_constant_16 (__x);				      \
+	 else {								      \
+	   unsigned short int __tmp = (unsigned short int) (__x);             \
+	   __asm__ __volatile__ (                                             \
+	      "sr   %0,%0\n"                                                  \
+	      "la   1,%1\n"                                                   \
+	      "icm  %0,2,1(1)\n"                                              \
+	      "ic   %0,0(1)"                                                  \
+	      : "=&d" (__v) : "m" (__tmp) : "1");                             \
+	 }                                                                    \
+	 __v; }))
+# endif
+#else
+/* This is better than nothing.  */
+static __inline unsigned short int
+__bswap_16 (unsigned short int __bsx)
+{
+  return __bswap_constant_16 (__bsx);
+}
+#endif