about summary refs log tree commit diff
diff options
context:
space:
mode:
-rw-r--r--ChangeLog5
-rw-r--r--sysdeps/x86_64/bits/byteswap.h133
2 files changed, 137 insertions, 1 deletions
diff --git a/ChangeLog b/ChangeLog
index b8c992af52..bf05d73bcb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,4 +1,7 @@
-2003-08-17  Andreas Jaeger  <aj@suse.de>
+2003-08-17  Juergen Kreileder <jk@blackdown.de>
+	    Andreas Jaeger  <aj@suse.de>
+
+	* sysdeps/x86_64/bits/byteswap.h: New file.
 
 	* sysdeps/unix/sysv/linux/i386/posix_fadvise64.S: Fix typo.
 
diff --git a/sysdeps/x86_64/bits/byteswap.h b/sysdeps/x86_64/bits/byteswap.h
new file mode 100644
index 0000000000..e1c861c75f
--- /dev/null
+++ b/sysdeps/x86_64/bits/byteswap.h
@@ -0,0 +1,133 @@
+/* Macros to swap the order of bytes in integer values.
+   Copyright (C) 1997, 1998, 2000, 2002, 2003 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#if !defined _BYTESWAP_H && !defined _NETINET_IN_H
+# error "Never use <bits/byteswap.h> directly; include <byteswap.h> instead."
+#endif
+
+#ifndef _BITS_BYTESWAP_H
+#define _BITS_BYTESWAP_H 1
+
+#include <bits/wordsize.h>
+
+/* Swap bytes in 16 bit value.  */
+#define __bswap_constant_16(x) \
+     ((((x) >> 8) & 0xff) | (((x) & 0xff) << 8))
+
+#if defined __GNUC__ && __GNUC__ >= 2
+# define __bswap_16(x) \
+     (__extension__							      \
+      ({ register unsigned short int __v, __x = (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 = (x); __bswap_constant_16 (__x); }))
+#endif
+
+
+/* Swap bytes in 32 bit value.  */
+#define __bswap_constant_32(x) \
+     ((((x) & 0xff000000) >> 24) | (((x) & 0x00ff0000) >>  8) |		      \
+      (((x) & 0x0000ff00) <<  8) | (((x) & 0x000000ff) << 24))
+
+#if defined __GNUC__ && __GNUC__ >= 2
+# if __WORDSIZE == 64 || (defined __i486__ || defined __pentium__	      \
+			  || defined __pentiumpro__ || defined __pentium4__   \
+			  || defined __k8__ || defined __athlon__	      \
+			  || defined __k6__)
+/* To swap the bytes in a word the i486 processors and up provide the
+   `bswap' opcode.  On i386 we have to use three instructions.  */
+#  define __bswap_32(x) \
+     (__extension__							      \
+      ({ register unsigned int __v, __x = (x);				      \
+	 if (__builtin_constant_p (__x))				      \
+	   __v = __bswap_constant_32 (__x);				      \
+	 else								      \
+	   __asm__ ("bswap %0" : "=r" (__v) : "0" (__x));		      \
+	 __v; }))
+# else
+#  define __bswap_32(x)							      \
+     (__extension__							      \
+      ({ register unsigned int __v, __x = (x);				      \
+	 if (__builtin_constant_p (__x))				      \
+	   __v = __bswap_constant_32 (__x);				      \
+	 else								      \
+	   __asm__ ("rorw $8, %w0;"					      \
+		    "rorl $16, %0;"					      \
+		    "rorw $8, %w0"					      \
+		    : "=r" (__v)					      \
+		    : "0" (__x)						      \
+		    : "cc");						      \
+	 __v; }))
+# endif
+#else
+# define __bswap_32(x) \
+     (__extension__							      \
+      ({ register unsigned int __x = (x); __bswap_constant_32 (__x); }))
+#endif
+
+
+#if defined __GNUC__ && __GNUC__ >= 2
+/* Swap bytes in 64 bit value.  */
+# define __bswap_constant_64(x) \
+     ((((x) & 0xff00000000000000ull) >> 56)				      \
+      | (((x) & 0x00ff000000000000ull) >> 40)				      \
+      | (((x) & 0x0000ff0000000000ull) >> 24)				      \
+      | (((x) & 0x000000ff00000000ull) >> 8)				      \
+      | (((x) & 0x00000000ff000000ull) << 8)				      \
+      | (((x) & 0x0000000000ff0000ull) << 24)				      \
+      | (((x) & 0x000000000000ff00ull) << 40)				      \
+      | (((x) & 0x00000000000000ffull) << 56))
+
+# if __WORDSIZE == 64
+#  define __bswap_64(x) \
+     (__extension__							      \
+      ({ register unsigned long __v, __x = (x);				      \
+	 if (__builtin_constant_p (__x))				      \
+	   __v = __bswap_constant_64 (__x);				      \
+	 else								      \
+	   __asm__ ("bswap %q0" : "=r" (__v) : "0" (__x));		      \
+	 __v; }))
+# else
+#  define __bswap_64(x) \
+     (__extension__                                                           \
+      ({ union { __extension__ unsigned long long int __ll;                   \
+                 unsigned int __l[2]; } __w, __r;                             \
+         if (__builtin_constant_p (x))                                        \
+           __r.__ll = __bswap_constant_64 (x);                                \
+         else                                                                 \
+           {                                                                  \
+             __w.__ll = (x);                                                  \
+             __r.__l[0] = __bswap_32 (__w.__l[1]);                            \
+             __r.__l[1] = __bswap_32 (__w.__l[0]);                            \
+           }                                                                  \
+         __r.__ll; }))
+# endif
+#endif
+
+#endif /* _BITS_BYTESWAP_H */