Subversion Repositories Kolibri OS

#ifndef _ASM_X86_HWEIGHT_H

#define _ASM_X86_HWEIGHT_H

#include 

#ifdef CONFIG_64BIT

/* popcnt %edi, %eax -- redundant REX prefix for alignment */

#define POPCNT32 ".byte 0xf3,0x40,0x0f,0xb8,0xc7"

/* popcnt %rdi, %rax */

#define POPCNT64 ".byte 0xf3,0x48,0x0f,0xb8,0xc7"

#define REG_IN "D"

#define REG_OUT "a"

#else

/* popcnt %eax, %eax */

#define POPCNT32 ".byte 0xf3,0x0f,0xb8,0xc0"

#define REG_IN "a"

#define REG_OUT "a"

#endif

/*

 * __sw_hweightXX are called from within the alternatives below

 * and callee-clobbered registers need to be taken care of. See

 * ARCH_HWEIGHT_CFLAGS in  for the respective

 * compiler switches.

 */

static __always_inline unsigned int __arch_hweight32(unsigned int w)

{

    unsigned int res = w - ((w >> 1) & 0x55555555);

    res = (res & 0x33333333) + ((res >> 2) & 0x33333333);

    res = (res + (res >> 4)) & 0x0F0F0F0F;

    res = res + (res >> 8);

    return (res + (res >> 16)) & 0x000000FF;

}

static inline unsigned int __arch_hweight16(unsigned int w)

{

	return __arch_hweight32(w & 0xffff);

}

static inline unsigned int __arch_hweight8(unsigned int w)

{

	return __arch_hweight32(w & 0xff);

}

#ifdef CONFIG_X86_32

static inline unsigned long __arch_hweight64(__u64 w)

{

	return  __arch_hweight32((u32)w) +

		__arch_hweight32((u32)(w >> 32));

}

#else

static __always_inline unsigned long __arch_hweight64(__u64 w)

{

	unsigned long res = 0;

	asm (ALTERNATIVE("call __sw_hweight64", POPCNT64, X86_FEATURE_POPCNT)

		     : "="REG_OUT (res)

		     : REG_IN (w));

	return res;

}

#endif /* CONFIG_X86_32 */

#endif