Commit 56a6b1eb authored by Alexander van Heukelum's avatar Alexander van Heukelum Committed by Ingo Molnar
Browse files

generic: implement __fls on all 64-bit archs 



Implement __fls on all 64-bit archs:

alpha has an implementation of fls64.
	Added __fls(x) = fls64(x) - 1.

ia64 has fls, but not __fls.
	Added __fls based on code of fls.

mips and powerpc have __ilog2, which is the same as __fls.
	Added __fls = __ilog2.

parisc, s390, sh and sparc64:
	Include generic __fls.

x86_64 already has __fls.

Signed-off-by: default avatarAlexander van Heukelum <heukelum@fastmail.fm>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 7d9dff22

include/asm-alpha/bitops.h

+5 −0
Original line number Diff line number Diff line
@@ -388,6 +388,11 @@ static inline int fls64(unsigned long x) 
}

#endif



static inline unsigned long __fls(unsigned long x)

{

	return fls64(x) - 1;

}



static inline int fls(int x)

{

	return fls64((unsigned int) x);

include/asm-ia64/bitops.h

+16 −0
Original line number Diff line number Diff line
@@ -407,6 +407,22 @@ fls (int t) 
	return ia64_popcnt(x);

}



/*

 * Find the last (most significant) bit set.  Undefined for x==0.

 * Bits are numbered from 0..63 (e.g., __fls(9) == 3).

 */

static inline unsigned long

__fls (unsigned long x)

{

	x |= x >> 1;

	x |= x >> 2;

	x |= x >> 4;

	x |= x >> 8;

	x |= x >> 16;

	x |= x >> 32;

	return ia64_popcnt(x) - 1;

}



#include <asm-generic/bitops/fls64.h>



/*

include/asm-mips/bitops.h

+5 −0
Original line number Diff line number Diff line
@@ -591,6 +591,11 @@ static inline int __ilog2(unsigned long x) 
	return 63 - lz;

}



static inline unsigned long __fls(unsigned long x)

{

	return __ilog2(x);

}



#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)



/*

include/asm-parisc/bitops.h

+1 −0
Original line number Diff line number Diff line
@@ -210,6 +210,7 @@ static __inline__ int fls(int x) 
	return ret;

}



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

#include <asm-generic/bitops/fls64.h>

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

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

include/asm-powerpc/bitops.h

+5 −0
Original line number Diff line number Diff line
@@ -313,6 +313,11 @@ static __inline__ int fls(unsigned int x) 
	return 32 - lz;

}



static __inline__ unsigned long __fls(unsigned long x)

{

	return __ilog2(x);

}



/*

 * 64-bit can do this using one cntlzd (count leading zeroes doubleword)

 * instruction; for 32-bit we use the generic version, which does two

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