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[/] [or1k/] [tags/] [LINUX_2_4_26_OR32/] [linux/] [linux-2.4/] [include/] [asm-alpha/] [byteorder.h] - Rev 1780

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#ifndef _ALPHA_BYTEORDER_H
#define _ALPHA_BYTEORDER_H
 
#include <asm/types.h>
 
#ifdef __GNUC__
 
static __inline __u32 __attribute__((__const)) __arch__swab32(__u32 x)
{
	/*
	 * Unfortunately, we can't use the 6 instruction sequence
	 * on ev6 since the latency of the UNPKBW is 3, which is
	 * pretty hard to hide.  Just in case a future implementation
	 * has a lower latency, here's the sequence (also by Mike Burrows)
	 *
	 * UNPKBW a0, v0       v0: 00AA00BB00CC00DD
	 * SLL v0, 24, a0      a0: BB00CC00DD000000
	 * BIS v0, a0, a0      a0: BBAACCBBDDCC00DD
	 * EXTWL a0, 6, v0     v0: 000000000000BBAA
	 * ZAP a0, 0xf3, a0    a0: 00000000DDCC0000
	 * ADDL a0, v0, v0     v0: ssssssssDDCCBBAA
	 */
 
	__u64 t0, t1, t2, t3;
 
	__asm__("inslh %1, 7, %0"	/* t0 : 0000000000AABBCC */
		: "=r"(t0) : "r"(x));
	__asm__("inswl %1, 3, %0"	/* t1 : 000000CCDD000000 */
		: "=r"(t1) : "r"(x));
 
	t1 |= t0;			/* t1 : 000000CCDDAABBCC */
	t2 = t1 >> 16;			/* t2 : 0000000000CCDDAA */
	t0 = t1 & 0xFF00FF00;		/* t0 : 00000000DD00BB00 */
	t3 = t2 & 0x00FF00FF;		/* t3 : 0000000000CC00AA */
	t1 = t0 + t3;			/* t1 : ssssssssDDCCBBAA */
 
	return t1;
}
 
#define __arch__swab32 __arch__swab32
 
#endif /* __GNUC__ */
 
#define __BYTEORDER_HAS_U64__
 
#include <linux/byteorder/little_endian.h>
 
#endif /* _ALPHA_BYTEORDER_H */
 

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