arch/x86/include/asm/bitops.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */
 #ifndef _ASM_X86_BITOPS_H
 #define _ASM_X86_BITOPS_H

 /*
  * Copyright 1992, Linus Torvalds.
  *
  * Note: inlines with more than a single statement should be marked
  * __always_inline to avoid problems with older gcc's inlining heuristics.
  */

 #ifndef _LINUX_BITOPS_H
 #error only <linux/bitops.h> can be included directly
 #endif

 #include <linux/compiler.h>
 #include <asm/alternative.h>
 #include <asm/rmwcc.h>
 #include <asm/barrier.h>

 #if BITS_PER_LONG == 32
 # define _BITOPS_LONG_SHIFT 5
 #elif BITS_PER_LONG == 64
 # define _BITOPS_LONG_SHIFT 6
 #else
 # error "Unexpected BITS_PER_LONG"
 #endif

 #define BIT_64(n)			(U64_C(1) << (n))

 /*
  * These have to be done with inline assembly: that way the bit-setting
  * is guaranteed to be atomic. All bit operations return 0 if the bit
  * was cleared before the operation and != 0 if it was not.
  *
  * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
  */

 #define RLONG_ADDR(x)			 "m" (*(volatile long *) (x))
 #define WBYTE_ADDR(x)			"+m" (*(volatile char *) (x))

 #define ADDR				RLONG_ADDR(addr)

 /*
  * We do the locked ops that don't return the old value as
  * a mask operation on a byte.
  */
 #define CONST_MASK_ADDR(nr, addr)	WBYTE_ADDR((void *)(addr) + ((nr)>>3))
 #define CONST_MASK(nr)			(1 << ((nr) & 7))

 static __always_inline void
 arch_set_bit(long nr, volatile unsigned long *addr)
 {
 	if (__builtin_constant_p(nr)) {
 		asm volatile(LOCK_PREFIX "orb %b1,%0"
 			: CONST_MASK_ADDR(nr, addr)
 			: "iq" (CONST_MASK(nr))
 			: "memory");
 	} else {
 		asm volatile(LOCK_PREFIX __ASM_SIZE(bts) " %1,%0"
 			: : RLONG_ADDR(addr), "Ir" (nr) : "memory");
 	}
 }

 static __always_inline void
 arch___set_bit(unsigned long nr, volatile unsigned long *addr)
 {
 	asm volatile(__ASM_SIZE(bts) " %1,%0" : : ADDR, "Ir" (nr) : "memory");
 }

 static __always_inline void
 arch_clear_bit(long nr, volatile unsigned long *addr)
 {
 	if (__builtin_constant_p(nr)) {
 		asm volatile(LOCK_PREFIX "andb %b1,%0"
 			: CONST_MASK_ADDR(nr, addr)
 			: "iq" (~CONST_MASK(nr)));
 	} else {
 		asm volatile(LOCK_PREFIX __ASM_SIZE(btr) " %1,%0"
 			: : RLONG_ADDR(addr), "Ir" (nr) : "memory");
 	}
 }

 static __always_inline void
 arch_clear_bit_unlock(long nr, volatile unsigned long *addr)
 {
 	barrier();
 	arch_clear_bit(nr, addr);
 }

 static __always_inline void
 arch___clear_bit(unsigned long nr, volatile unsigned long *addr)
 {
 	asm volatile(__ASM_SIZE(btr) " %1,%0" : : ADDR, "Ir" (nr) : "memory");
 }

 static __always_inline bool
 arch_clear_bit_unlock_is_negative_byte(long nr, volatile unsigned long *addr)
 {
 	bool negative;
 	asm volatile(LOCK_PREFIX "andb %2,%1"
 		CC_SET(s)
 		: CC_OUT(s) (negative), WBYTE_ADDR(addr)
 		: "ir" ((char) ~(1 << nr)) : "memory");
 	return negative;
 }
 #define arch_clear_bit_unlock_is_negative_byte                                 \
 	arch_clear_bit_unlock_is_negative_byte

 static __always_inline void
 arch___clear_bit_unlock(long nr, volatile unsigned long *addr)
 {
 	arch___clear_bit(nr, addr);
 }

 static __always_inline void
 arch___change_bit(unsigned long nr, volatile unsigned long *addr)
 {
 	asm volatile(__ASM_SIZE(btc) " %1,%0" : : ADDR, "Ir" (nr) : "memory");
 }

 static __always_inline void
 arch_change_bit(long nr, volatile unsigned long *addr)
 {
 	if (__builtin_constant_p(nr)) {
 		asm volatile(LOCK_PREFIX "xorb %b1,%0"
 			: CONST_MASK_ADDR(nr, addr)
 			: "iq" (CONST_MASK(nr)));
 	} else {
 		asm volatile(LOCK_PREFIX __ASM_SIZE(btc) " %1,%0"
 			: : RLONG_ADDR(addr), "Ir" (nr) : "memory");
 	}
 }

 static __always_inline bool
 arch_test_and_set_bit(long nr, volatile unsigned long *addr)
 {
 	return GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(bts), *addr, c, "Ir", nr);
 }

 static __always_inline bool
 arch_test_and_set_bit_lock(long nr, volatile unsigned long *addr)
 {
 	return arch_test_and_set_bit(nr, addr);
 }

 static __always_inline bool
 arch___test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
 {
 	bool oldbit;

 	asm(__ASM_SIZE(bts) " %2,%1"
 	    CC_SET(c)
 	    : CC_OUT(c) (oldbit)
 	    : ADDR, "Ir" (nr) : "memory");
 	return oldbit;
 }

 static __always_inline bool
 arch_test_and_clear_bit(long nr, volatile unsigned long *addr)
 {
 	return GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(btr), *addr, c, "Ir", nr);
 }

 /*
  * Note: the operation is performed atomically with respect to
  * the local CPU, but not other CPUs. Portable code should not
  * rely on this behaviour.
  * KVM relies on this behaviour on x86 for modifying memory that is also
  * accessed from a hypervisor on the same CPU if running in a VM: don't change
  * this without also updating arch/x86/kernel/kvm.c
  */
 static __always_inline bool
 arch___test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
 {
 	bool oldbit;

 	asm volatile(__ASM_SIZE(btr) " %2,%1"
 		     CC_SET(c)
 		     : CC_OUT(c) (oldbit)
 		     : ADDR, "Ir" (nr) : "memory");
 	return oldbit;
 }

 static __always_inline bool
 arch___test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
 {
 	bool oldbit;

 	asm volatile(__ASM_SIZE(btc) " %2,%1"
 		     CC_SET(c)
 		     : CC_OUT(c) (oldbit)
 		     : ADDR, "Ir" (nr) : "memory");

 	return oldbit;
 }

 static __always_inline bool
 arch_test_and_change_bit(long nr, volatile unsigned long *addr)
 {
 	return GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(btc), *addr, c, "Ir", nr);
 }

 static __always_inline bool constant_test_bit(long nr, const volatile unsigned long *addr)
 {
 	return ((1UL << (nr & (BITS_PER_LONG-1))) &
 		(addr[nr >> _BITOPS_LONG_SHIFT])) != 0;
 }

 static __always_inline bool constant_test_bit_acquire(long nr, const volatile unsigned long *addr)
 {
 	bool oldbit;

 	asm volatile("testb %2,%1"
 		     CC_SET(nz)
 		     : CC_OUT(nz) (oldbit)
 		     : "m" (((unsigned char *)addr)[nr >> 3]),
 		       "i" (1 << (nr & 7))
 		     :"memory");

 	return oldbit;
 }

 static __always_inline bool variable_test_bit(long nr, volatile const unsigned long *addr)
 {
 	bool oldbit;

 	asm volatile(__ASM_SIZE(bt) " %2,%1"
 		     CC_SET(c)
 		     : CC_OUT(c) (oldbit)
 		     : "m" (*(unsigned long *)addr), "Ir" (nr) : "memory");

 	return oldbit;
 }

 static __always_inline bool
 arch_test_bit(unsigned long nr, const volatile unsigned long *addr)
 {
 	return __builtin_constant_p(nr) ? constant_test_bit(nr, addr) :
 					  variable_test_bit(nr, addr);
 }

 static __always_inline bool
 arch_test_bit_acquire(unsigned long nr, const volatile unsigned long *addr)
 {
 	return __builtin_constant_p(nr) ? constant_test_bit_acquire(nr, addr) :
 					  variable_test_bit(nr, addr);
 }

 static __always_inline unsigned long variable__ffs(unsigned long word)
 {
 	asm("rep; bsf %1,%0"
 		: "=r" (word)
 		: "rm" (word));
 	return word;
 }

 /**
  * __ffs - find first set bit in word
  * @word: The word to search
  *
  * Undefined if no bit exists, so code should check against 0 first.
  */
 #define __ffs(word)				\
 	(__builtin_constant_p(word) ?		\
 	 (unsigned long)__builtin_ctzl(word) :	\
 	 variable__ffs(word))

 static __always_inline unsigned long variable_ffz(unsigned long word)
 {
 	asm("rep; bsf %1,%0"
 		: "=r" (word)
 		: "r" (~word));
 	return word;
 }

 /**
  * ffz - find first zero bit in word
  * @word: The word to search
  *
  * Undefined if no zero exists, so code should check against ~0UL first.
  */
 #define ffz(word)				\
 	(__builtin_constant_p(word) ?		\
 	 (unsigned long)__builtin_ctzl(~word) :	\
 	 variable_ffz(word))

 /*
  * __fls: find last set bit in word
  * @word: The word to search
  *
  * Undefined if no set bit exists, so code should check against 0 first.
  */
 static __always_inline unsigned long __fls(unsigned long word)
 {
 	asm("bsr %1,%0"
 	    : "=r" (word)
 	    : "rm" (word));
 	return word;
 }

 #undef ADDR

 #ifdef __KERNEL__
 static __always_inline int variable_ffs(int x)
 {
 	int r;

 #ifdef CONFIG_X86_64
 	/*
 	 * AMD64 says BSFL won't clobber the dest reg if x==0; Intel64 says the
 	 * dest reg is undefined if x==0, but their CPU architect says its
 	 * value is written to set it to the same as before, except that the
 	 * top 32 bits will be cleared.
 	 *
 	 * We cannot do this on 32 bits because at the very least some
 	 * 486 CPUs did not behave this way.
 	 */
 	asm("bsfl %1,%0"
 	    : "=r" (r)
 	    : "rm" (x), "0" (-1));
 #elif defined(CONFIG_X86_CMOV)
 	asm("bsfl %1,%0\n\t"
 	    "cmovzl %2,%0"
 	    : "=&r" (r) : "rm" (x), "r" (-1));
 #else
 	asm("bsfl %1,%0\n\t"
 	    "jnz 1f\n\t"
 	    "movl $-1,%0\n"
 	    "1:" : "=r" (r) : "rm" (x));
 #endif
 	return r + 1;
 }

 /**
  * ffs - find first set bit in word
  * @x: the word to search
  *
  * This is defined the same way as the libc and compiler builtin ffs
  * routines, therefore differs in spirit from the other bitops.
  *
  * ffs(value) returns 0 if value is 0 or the position of the first
  * set bit if value is nonzero. The first (least significant) bit
  * is at position 1.
  */
 #define ffs(x) (__builtin_constant_p(x) ? __builtin_ffs(x) : variable_ffs(x))

 /**
  * fls - find last set bit in word
  * @x: the word to search
  *
  * This is defined in a similar way as the libc and compiler builtin
  * ffs, but returns the position of the most significant set bit.
  *
  * fls(value) returns 0 if value is 0 or the position of the last
  * set bit if value is nonzero. The last (most significant) bit is
  * at position 32.
  */
 static __always_inline int fls(unsigned int x)
 {
 	int r;

 #ifdef CONFIG_X86_64
 	/*
 	 * AMD64 says BSRL won't clobber the dest reg if x==0; Intel64 says the
 	 * dest reg is undefined if x==0, but their CPU architect says its
 	 * value is written to set it to the same as before, except that the
 	 * top 32 bits will be cleared.
 	 *
 	 * We cannot do this on 32 bits because at the very least some
 	 * 486 CPUs did not behave this way.
 	 */
 	asm("bsrl %1,%0"
 	    : "=r" (r)
 	    : "rm" (x), "0" (-1));
 #elif defined(CONFIG_X86_CMOV)
 	asm("bsrl %1,%0\n\t"
 	    "cmovzl %2,%0"
 	    : "=&r" (r) : "rm" (x), "rm" (-1));
 #else
 	asm("bsrl %1,%0\n\t"
 	    "jnz 1f\n\t"
 	    "movl $-1,%0\n"
 	    "1:" : "=r" (r) : "rm" (x));
 #endif
 	return r + 1;
 }

 /**
  * fls64 - find last set bit in a 64-bit word
  * @x: the word to search
  *
  * This is defined in a similar way as the libc and compiler builtin
  * ffsll, but returns the position of the most significant set bit.
  *
  * fls64(value) returns 0 if value is 0 or the position of the last
  * set bit if value is nonzero. The last (most significant) bit is
  * at position 64.
  */
 #ifdef CONFIG_X86_64
 static __always_inline int fls64(__u64 x)
 {
 	int bitpos = -1;
 	/*
 	 * AMD64 says BSRQ won't clobber the dest reg if x==0; Intel64 says the
 	 * dest reg is undefined if x==0, but their CPU architect says its
 	 * value is written to set it to the same as before.
 	 */
 	asm("bsrq %1,%q0"
 	    : "+r" (bitpos)
 	    : "rm" (x));
 	return bitpos + 1;
 }
 #else
 #include <asm-generic/bitops/fls64.h>
 #endif

 #include <asm-generic/bitops/sched.h>

 #include <asm/arch_hweight.h>

 #include <asm-generic/bitops/const_hweight.h>

 #include <asm-generic/bitops/instrumented-atomic.h>
 #include <asm-generic/bitops/instrumented-non-atomic.h>
 #include <asm-generic/bitops/instrumented-lock.h>

 #include <asm-generic/bitops/le.h>

 #include <asm-generic/bitops/ext2-atomic-setbit.h>

 #endif /* __KERNEL__ */
 #endif /* _ASM_X86_BITOPS_H */
	/* SPDX-License-Identifier: GPL-2.0 */
	#ifndef _ASM_X86_BITOPS_H
	#define _ASM_X86_BITOPS_H

	/*
	* Copyright 1992, Linus Torvalds.
	*
	* Note: inlines with more than a single statement should be marked
	* __always_inline to avoid problems with older gcc's inlining heuristics.
	*/

	#ifndef _LINUX_BITOPS_H
	#error only <linux/bitops.h> can be included directly
	#endif

	#include <linux/compiler.h>
	#include <asm/alternative.h>
	#include <asm/rmwcc.h>
	#include <asm/barrier.h>

	#if BITS_PER_LONG == 32
	# define _BITOPS_LONG_SHIFT 5
	#elif BITS_PER_LONG == 64
	# define _BITOPS_LONG_SHIFT 6
	#else
	# error "Unexpected BITS_PER_LONG"
	#endif

	#define BIT_64(n) (U64_C(1) << (n))

	/*
	* These have to be done with inline assembly: that way the bit-setting
	* is guaranteed to be atomic. All bit operations return 0 if the bit
	* was cleared before the operation and != 0 if it was not.
	*
	* bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
	*/

	#define RLONG_ADDR(x) "m" ((volatile long ) (x))
	#define WBYTE_ADDR(x) "+m" ((volatile char ) (x))

	#define ADDR RLONG_ADDR(addr)

	/*
	* We do the locked ops that don't return the old value as
	* a mask operation on a byte.
	*/
	#define CONST_MASK_ADDR(nr, addr) WBYTE_ADDR((void *)(addr) + ((nr)>>3))
	#define CONST_MASK(nr) (1 << ((nr) & 7))

	static __always_inline void
	arch_set_bit(long nr, volatile unsigned long *addr)
	{
	if (__builtin_constant_p(nr)) {
	asm volatile(LOCK_PREFIX "orb %b1,%0"
	: CONST_MASK_ADDR(nr, addr)
	: "iq" (CONST_MASK(nr))
	: "memory");
	} else {
	asm volatile(LOCK_PREFIX __ASM_SIZE(bts) " %1,%0"
	: : RLONG_ADDR(addr), "Ir" (nr) : "memory");
	}
	}

	static __always_inline void
	arch___set_bit(unsigned long nr, volatile unsigned long *addr)
	{
	asm volatile(__ASM_SIZE(bts) " %1,%0" : : ADDR, "Ir" (nr) : "memory");
	}

	static __always_inline void
	arch_clear_bit(long nr, volatile unsigned long *addr)
	{
	if (__builtin_constant_p(nr)) {
	asm volatile(LOCK_PREFIX "andb %b1,%0"
	: CONST_MASK_ADDR(nr, addr)
	: "iq" (~CONST_MASK(nr)));
	} else {
	asm volatile(LOCK_PREFIX __ASM_SIZE(btr) " %1,%0"
	: : RLONG_ADDR(addr), "Ir" (nr) : "memory");
	}
	}

	static __always_inline void
	arch_clear_bit_unlock(long nr, volatile unsigned long *addr)
	{
	barrier();
	arch_clear_bit(nr, addr);
	}

	static __always_inline void
	arch___clear_bit(unsigned long nr, volatile unsigned long *addr)
	{
	asm volatile(__ASM_SIZE(btr) " %1,%0" : : ADDR, "Ir" (nr) : "memory");
	}

	static __always_inline bool
	arch_clear_bit_unlock_is_negative_byte(long nr, volatile unsigned long *addr)
	{
	bool negative;
	asm volatile(LOCK_PREFIX "andb %2,%1"
	CC_SET(s)
	: CC_OUT(s) (negative), WBYTE_ADDR(addr)
	: "ir" ((char) ~(1 << nr)) : "memory");
	return negative;
	}
	#define arch_clear_bit_unlock_is_negative_byte \
	arch_clear_bit_unlock_is_negative_byte

	static __always_inline void
	arch___clear_bit_unlock(long nr, volatile unsigned long *addr)
	{
	arch___clear_bit(nr, addr);
	}

	static __always_inline void
	arch___change_bit(unsigned long nr, volatile unsigned long *addr)
	{
	asm volatile(__ASM_SIZE(btc) " %1,%0" : : ADDR, "Ir" (nr) : "memory");
	}

	static __always_inline void
	arch_change_bit(long nr, volatile unsigned long *addr)
	{
	if (__builtin_constant_p(nr)) {
	asm volatile(LOCK_PREFIX "xorb %b1,%0"
	: CONST_MASK_ADDR(nr, addr)
	: "iq" (CONST_MASK(nr)));
	} else {
	asm volatile(LOCK_PREFIX __ASM_SIZE(btc) " %1,%0"
	: : RLONG_ADDR(addr), "Ir" (nr) : "memory");
	}
	}

	static __always_inline bool
	arch_test_and_set_bit(long nr, volatile unsigned long *addr)
	{
	return GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(bts), *addr, c, "Ir", nr);
	}

	static __always_inline bool
	arch_test_and_set_bit_lock(long nr, volatile unsigned long *addr)
	{
	return arch_test_and_set_bit(nr, addr);
	}

	static __always_inline bool
	arch___test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
	{
	bool oldbit;

	asm(__ASM_SIZE(bts) " %2,%1"
	CC_SET(c)
	: CC_OUT(c) (oldbit)
	: ADDR, "Ir" (nr) : "memory");
	return oldbit;
	}

	static __always_inline bool
	arch_test_and_clear_bit(long nr, volatile unsigned long *addr)
	{
	return GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(btr), *addr, c, "Ir", nr);
	}

	/*
	* Note: the operation is performed atomically with respect to
	* the local CPU, but not other CPUs. Portable code should not
	* rely on this behaviour.
	* KVM relies on this behaviour on x86 for modifying memory that is also
	* accessed from a hypervisor on the same CPU if running in a VM: don't change
	* this without also updating arch/x86/kernel/kvm.c
	*/
	static __always_inline bool
	arch___test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
	{
	bool oldbit;

	asm volatile(__ASM_SIZE(btr) " %2,%1"
	CC_SET(c)
	: CC_OUT(c) (oldbit)
	: ADDR, "Ir" (nr) : "memory");
	return oldbit;
	}

	static __always_inline bool
	arch___test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
	{
	bool oldbit;

	asm volatile(__ASM_SIZE(btc) " %2,%1"
	CC_SET(c)
	: CC_OUT(c) (oldbit)
	: ADDR, "Ir" (nr) : "memory");

	return oldbit;
	}

	static __always_inline bool
	arch_test_and_change_bit(long nr, volatile unsigned long *addr)
	{
	return GEN_BINARY_RMWcc(LOCK_PREFIX __ASM_SIZE(btc), *addr, c, "Ir", nr);
	}

	static __always_inline bool constant_test_bit(long nr, const volatile unsigned long *addr)
	{
	return ((1UL << (nr & (BITS_PER_LONG-1))) &
	(addr[nr >> _BITOPS_LONG_SHIFT])) != 0;
	}

	static __always_inline bool constant_test_bit_acquire(long nr, const volatile unsigned long *addr)
	{
	bool oldbit;

	asm volatile("testb %2,%1"
	CC_SET(nz)
	: CC_OUT(nz) (oldbit)
	: "m" (((unsigned char *)addr)[nr >> 3]),
	"i" (1 << (nr & 7))
	:"memory");

	return oldbit;
	}

	static __always_inline bool variable_test_bit(long nr, volatile const unsigned long *addr)
	{
	bool oldbit;

	asm volatile(__ASM_SIZE(bt) " %2,%1"
	CC_SET(c)
	: CC_OUT(c) (oldbit)
	: "m" ((unsigned long )addr), "Ir" (nr) : "memory");

	return oldbit;
	}

	static __always_inline bool
	arch_test_bit(unsigned long nr, const volatile unsigned long *addr)
	{
	return __builtin_constant_p(nr) ? constant_test_bit(nr, addr) :
	variable_test_bit(nr, addr);
	}

	static __always_inline bool
	arch_test_bit_acquire(unsigned long nr, const volatile unsigned long *addr)
	{
	return __builtin_constant_p(nr) ? constant_test_bit_acquire(nr, addr) :
	variable_test_bit(nr, addr);
	}

	static __always_inline unsigned long variable__ffs(unsigned long word)
	{
	asm("rep; bsf %1,%0"
	: "=r" (word)
	: "rm" (word));
	return word;
	}

	/**
	* __ffs - find first set bit in word
	* @word: The word to search
	*
	* Undefined if no bit exists, so code should check against 0 first.
	*/
	#define __ffs(word) \
	(__builtin_constant_p(word) ? \
	(unsigned long)__builtin_ctzl(word) : \
	variable__ffs(word))

	static __always_inline unsigned long variable_ffz(unsigned long word)
	{
	asm("rep; bsf %1,%0"
	: "=r" (word)
	: "r" (~word));
	return word;
	}

	/**
	* ffz - find first zero bit in word
	* @word: The word to search
	*
	* Undefined if no zero exists, so code should check against ~0UL first.
	*/
	#define ffz(word) \
	(__builtin_constant_p(word) ? \
	(unsigned long)__builtin_ctzl(~word) : \
	variable_ffz(word))

	/*
	* __fls: find last set bit in word
	* @word: The word to search
	*
	* Undefined if no set bit exists, so code should check against 0 first.
	*/
	static __always_inline unsigned long __fls(unsigned long word)
	{
	asm("bsr %1,%0"
	: "=r" (word)
	: "rm" (word));
	return word;
	}

	#undef ADDR

	#ifdef __KERNEL__
	static __always_inline int variable_ffs(int x)
	{
	int r;

	#ifdef CONFIG_X86_64
	/*
	* AMD64 says BSFL won't clobber the dest reg if x==0; Intel64 says the
	* dest reg is undefined if x==0, but their CPU architect says its
	* value is written to set it to the same as before, except that the
	* top 32 bits will be cleared.
	*
	* We cannot do this on 32 bits because at the very least some
	* 486 CPUs did not behave this way.
	*/
	asm("bsfl %1,%0"
	: "=r" (r)
	: "rm" (x), "0" (-1));
	#elif defined(CONFIG_X86_CMOV)
	asm("bsfl %1,%0\n\t"
	"cmovzl %2,%0"
	: "=&r" (r) : "rm" (x), "r" (-1));
	#else
	asm("bsfl %1,%0\n\t"
	"jnz 1f\n\t"
	"movl $-1,%0\n"
	"1:" : "=r" (r) : "rm" (x));
	#endif
	return r + 1;
	}

	/**
	* ffs - find first set bit in word
	* @x: the word to search
	*
	* This is defined the same way as the libc and compiler builtin ffs
	* routines, therefore differs in spirit from the other bitops.
	*
	* ffs(value) returns 0 if value is 0 or the position of the first
	* set bit if value is nonzero. The first (least significant) bit
	* is at position 1.
	*/
	#define ffs(x) (__builtin_constant_p(x) ? __builtin_ffs(x) : variable_ffs(x))

	/**
	* fls - find last set bit in word
	* @x: the word to search
	*
	* This is defined in a similar way as the libc and compiler builtin
	* ffs, but returns the position of the most significant set bit.
	*
	* fls(value) returns 0 if value is 0 or the position of the last
	* set bit if value is nonzero. The last (most significant) bit is
	* at position 32.
	*/
	static __always_inline int fls(unsigned int x)
	{
	int r;

	#ifdef CONFIG_X86_64
	/*
	* AMD64 says BSRL won't clobber the dest reg if x==0; Intel64 says the
	* dest reg is undefined if x==0, but their CPU architect says its
	* value is written to set it to the same as before, except that the
	* top 32 bits will be cleared.
	*
	* We cannot do this on 32 bits because at the very least some
	* 486 CPUs did not behave this way.
	*/
	asm("bsrl %1,%0"
	: "=r" (r)
	: "rm" (x), "0" (-1));
	#elif defined(CONFIG_X86_CMOV)
	asm("bsrl %1,%0\n\t"
	"cmovzl %2,%0"
	: "=&r" (r) : "rm" (x), "rm" (-1));
	#else
	asm("bsrl %1,%0\n\t"
	"jnz 1f\n\t"
	"movl $-1,%0\n"
	"1:" : "=r" (r) : "rm" (x));
	#endif
	return r + 1;
	}

	/**
	* fls64 - find last set bit in a 64-bit word
	* @x: the word to search
	*
	* This is defined in a similar way as the libc and compiler builtin
	* ffsll, but returns the position of the most significant set bit.
	*
	* fls64(value) returns 0 if value is 0 or the position of the last
	* set bit if value is nonzero. The last (most significant) bit is
	* at position 64.
	*/
	#ifdef CONFIG_X86_64
	static __always_inline int fls64(__u64 x)
	{
	int bitpos = -1;
	/*
	* AMD64 says BSRQ won't clobber the dest reg if x==0; Intel64 says the
	* dest reg is undefined if x==0, but their CPU architect says its
	* value is written to set it to the same as before.
	*/
	asm("bsrq %1,%q0"
	: "+r" (bitpos)
	: "rm" (x));
	return bitpos + 1;
	}
	#else
	#include <asm-generic/bitops/fls64.h>
	#endif

	#include <asm-generic/bitops/sched.h>

	#include <asm/arch_hweight.h>

	#include <asm-generic/bitops/const_hweight.h>

	#include <asm-generic/bitops/instrumented-atomic.h>
	#include <asm-generic/bitops/instrumented-non-atomic.h>
	#include <asm-generic/bitops/instrumented-lock.h>

	#include <asm-generic/bitops/le.h>

	#include <asm-generic/bitops/ext2-atomic-setbit.h>

	#endif /* __KERNEL__ */
	#endif /* _ASM_X86_BITOPS_H */