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Diffstat (limited to 'libc/sysdeps/linux/common/bits/byteswap-common.h')
-rw-r--r--libc/sysdeps/linux/common/bits/byteswap-common.h109
1 files changed, 57 insertions, 52 deletions
diff --git a/libc/sysdeps/linux/common/bits/byteswap-common.h b/libc/sysdeps/linux/common/bits/byteswap-common.h
index 4941d4768..0effea689 100644
--- a/libc/sysdeps/linux/common/bits/byteswap-common.h
+++ b/libc/sysdeps/linux/common/bits/byteswap-common.h
@@ -1,5 +1,5 @@
/* Macros to swap the order of bytes in integer values.
- Copyright (C) 1997,1998,2000,2001,2002,2005 Free Software Foundation, Inc.
+ Copyright (C) 1997-2016 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
@@ -16,54 +16,40 @@
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
-#if !defined _BYTESWAP_H && !defined _NETINET_IN_H
+#if !defined _BYTESWAP_H && !defined _NETINET_IN_H && !defined _ENDIAN_H
# error "Never use <bits/byteswap.h> directly; include <byteswap.h> instead."
#endif
#ifndef _BITS_BYTESWAP_H
#define _BITS_BYTESWAP_H 1
+#include <features.h>
+#include <bits/types.h>
+
/* Swap bytes in 16 bit value. */
#define __bswap_constant_16(x) \
- ((((x) >> 8) & 0xffu) | (((x) & 0xffu) << 8))
+ ((unsigned short int)((((x) >> 8) & 0xffu) | (((x) & 0xffu) << 8)))
-#ifndef __bswap_non_constant_16
-# define __bswap_non_constant_16(x) __bswap_constant_16(x)
-#endif
-#ifdef __GNUC__
-# define __bswap_16(x) \
- (__extension__ \
- ({ unsigned short int __bsv, __bsx = (x); \
- if (__builtin_constant_p (__bsx)) \
- __bsv = __bswap_constant_16 (__bsx); \
- else \
- __bsv = __bswap_non_constant_16 (__bsx); \
- __bsv; }))
-#else
-static __inline unsigned short int
-__bswap_16 (unsigned short int __bsx)
-{
- return __bswap_constant_16 (__bsx);
-}
-#endif
+/* Get __bswap_16. */
+#include <bits/byteswap-16.h>
/* Swap bytes in 32 bit value. */
#define __bswap_constant_32(x) \
((((x) & 0xff000000u) >> 24) | (((x) & 0x00ff0000u) >> 8) | \
(((x) & 0x0000ff00u) << 8) | (((x) & 0x000000ffu) << 24))
-#ifndef __bswap_non_constant_32
-# define __bswap_non_constant_32(x) __bswap_constant_32(x)
-#endif
#ifdef __GNUC__
-# define __bswap_32(x) \
- (__extension__ \
- ({ unsigned int __bsv, __bsx = (x); \
- if (__builtin_constant_p (__bsx)) \
- __bsv = __bswap_constant_32 (__bsx); \
- else \
- __bsv = __bswap_non_constant_32 (__bsx); \
- __bsv; }))
+# if __GNUC_PREREQ (4, 3)
+static __inline unsigned int
+__bswap_32 (unsigned int __bsx)
+{
+ return __builtin_bswap32 (__bsx);
+}
+# else
+# define __bswap_32(x) \
+ (__extension__ \
+ ({ unsigned int __bsx = (x); __bswap_constant_32 (__bsx); }))
+# endif
#else
static __inline unsigned int
__bswap_32 (unsigned int __bsx)
@@ -72,8 +58,40 @@ __bswap_32 (unsigned int __bsx)
}
#endif
-#if defined __GNUC__ && __GNUC__ >= 2
/* Swap bytes in 64 bit value. */
+#if __GNUC_PREREQ (2, 0)
+# define __bswap_constant_64(x) \
+ (__extension__ ((((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 __GNUC_PREREQ (4, 3)
+static __inline __uint64_t
+__bswap_64 (__uint64_t __bsx)
+{
+ return __builtin_bswap64 (__bsx);
+}
+# else
+# define __bswap_64(x) \
+ (__extension__ \
+ ({ union { __extension__ __uint64_t __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
+#else
# define __bswap_constant_64(x) \
((((x) & 0xff00000000000000ull) >> 56) \
| (((x) & 0x00ff000000000000ull) >> 40) \
@@ -84,24 +102,11 @@ __bswap_32 (unsigned int __bsx)
| (((x) & 0x000000000000ff00ull) << 40) \
| (((x) & 0x00000000000000ffull) << 56))
-# ifndef __bswap_non_constant_64
-# define __bswap_non_constant_64(x) \
- (__extension__ \
- ({ union { __extension__ unsigned long long int __ll; \
- unsigned int __l[2]; } __w, __r; \
- __w.__ll = (x); \
- __r.__l[0] = __bswap_non_constant_32 (__w.__l[1]); \
- __r.__l[1] = __bswap_non_constant_32 (__w.__l[0]); \
- __r.__ll; }))
-# endif
-# define __bswap_64(x) \
- (__extension__ \
- ({ __extension__ unsigned long long int __ll; \
- if (__builtin_constant_p (x)) \
- __ll = __bswap_constant_64 (x); \
- else \
- __ll = __bswap_non_constant_64 (x); \
- __ll; }))
+static __inline __uint64_t
+__bswap_64 (__uint64_t __bsx)
+{
+ return __bswap_constant_64 (__bsx);
+}
#endif
#endif /* _BITS_BYTESWAP_H */