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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-i386/byteorder.h
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/asm-i386/byteorder.h')
-rw-r--r--include/asm-i386/byteorder.h59
1 files changed, 59 insertions, 0 deletions
diff --git a/include/asm-i386/byteorder.h b/include/asm-i386/byteorder.h
new file mode 100644
index 000000000000..a0d73f48d5be
--- /dev/null
+++ b/include/asm-i386/byteorder.h
@@ -0,0 +1,59 @@
+#ifndef _I386_BYTEORDER_H
+#define _I386_BYTEORDER_H
+
+#include <asm/types.h>
+#include <linux/compiler.h>
+
+#ifdef __GNUC__
+
+/* For avoiding bswap on i386 */
+#ifdef __KERNEL__
+#include <linux/config.h>
+#endif
+
+static __inline__ __attribute_const__ __u32 ___arch__swab32(__u32 x)
+{
+#ifdef CONFIG_X86_BSWAP
+ __asm__("bswap %0" : "=r" (x) : "0" (x));
+#else
+ __asm__("xchgb %b0,%h0\n\t" /* swap lower bytes */
+ "rorl $16,%0\n\t" /* swap words */
+ "xchgb %b0,%h0" /* swap higher bytes */
+ :"=q" (x)
+ : "0" (x));
+#endif
+ return x;
+}
+
+static __inline__ __attribute_const__ __u64 ___arch__swab64(__u64 val)
+{
+ union {
+ struct { __u32 a,b; } s;
+ __u64 u;
+ } v;
+ v.u = val;
+#ifdef CONFIG_X86_BSWAP
+ asm("bswapl %0 ; bswapl %1 ; xchgl %0,%1"
+ : "=r" (v.s.a), "=r" (v.s.b)
+ : "0" (v.s.a), "1" (v.s.b));
+#else
+ v.s.a = ___arch__swab32(v.s.a);
+ v.s.b = ___arch__swab32(v.s.b);
+ asm("xchgl %0,%1" : "=r" (v.s.a), "=r" (v.s.b) : "0" (v.s.a), "1" (v.s.b));
+#endif
+ return v.u;
+}
+
+/* Do not define swab16. Gcc is smart enough to recognize "C" version and
+ convert it into rotation or exhange. */
+
+#define __arch__swab64(x) ___arch__swab64(x)
+#define __arch__swab32(x) ___arch__swab32(x)
+
+#define __BYTEORDER_HAS_U64__
+
+#endif /* __GNUC__ */
+
+#include <linux/byteorder/little_endian.h>
+
+#endif /* _I386_BYTEORDER_H */