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/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
*/
#ifndef _ASM_BITOPS_H
#define _ASM_BITOPS_H
#ifndef _LINUX_BITOPS_H
#error only <linux/bitops.h> can be included directly
#endif
#ifndef __ASSEMBLY__
#include <linux/types.h>
#include <linux/compiler.h>
#ifdef CONFIG_ISA_ARCOMPACT
/*
* Count the number of zeros, starting from MSB
* Helper for fls( ) friends
* This is a pure count, so (1-32) or (0-31) doesn't apply
* It could be 0 to 32, based on num of 0's in there
* clz(0x8000_0000) = 0, clz(0xFFFF_FFFF)=0, clz(0) = 32, clz(1) = 31
*/
static inline __attribute__ ((const)) int clz(unsigned int x)
{
unsigned int res;
__asm__ __volatile__(
" norm.f %0, %1 \n"
" mov.n %0, 0 \n"
" add.p %0, %0, 1 \n"
: "=r"(res)
: "r"(x)
: "cc");
return res;
}
static inline int constant_fls(unsigned int x)
{
int r = 32;
if (!x)
return 0;
if (!(x & 0xffff0000u)) {
x <<= 16;
r -= 16;
}
if (!(x & 0xff000000u)) {
x <<= 8;
r -= 8;
}
if (!(x & 0xf0000000u)) {
x <<= 4;
r -= 4;
}
if (!(x & 0xc0000000u)) {
x <<= 2;
r -= 2;
}
if (!(x & 0x80000000u))
r -= 1;
return r;
}
/*
* fls = Find Last Set in word
* @result: [1-32]
* fls(1) = 1, fls(0x80000000) = 32, fls(0) = 0
*/
static inline __attribute__ ((const)) int fls(unsigned int x)
{
if (__builtin_constant_p(x))
return constant_fls(x);
return 32 - clz(x);
}
/*
* __fls: Similar to fls, but zero based (0-31)
*/
static inline __attribute__ ((const)) int __fls(unsigned long x)
{
if (!x)
return 0;
else
return fls(x) - 1;
}
/*
* ffs = Find First Set in word (LSB to MSB)
* @result: [1-32], 0 if all 0's
*/
#define ffs(x) ({ unsigned long __t = (x); fls(__t & -__t); })
/*
* __ffs: Similar to ffs, but zero based (0-31)
*/
static inline __attribute__ ((const)) unsigned long __ffs(unsigned long word)
{
if (!word)
return word;
return ffs(word) - 1;
}
#else /* CONFIG_ISA_ARCV2 */
/*
* fls = Find Last Set in word
* @result: [1-32]
* fls(1) = 1, fls(0x80000000) = 32, fls(0) = 0
*/
static inline __attribute__ ((const)) int fls(unsigned int x)
{
int n;
asm volatile(
" fls.f %0, %1 \n" /* 0:31; 0(Z) if src 0 */
" add.nz %0, %0, 1 \n" /* 0:31 -> 1:32 */
: "=r"(n) /* Early clobber not needed */
: "r"(x)
: "cc");
return n;
}
/*
* __fls: Similar to fls, but zero based (0-31). Also 0 if no bit set
*/
static inline __attribute__ ((const)) int __fls(unsigned long x)
{
/* FLS insn has exactly same semantics as the API */
return __builtin_arc_fls(x);
}
/*
* ffs = Find First Set in word (LSB to MSB)
* @result: [1-32], 0 if all 0's
*/
static inline __attribute__ ((const)) int ffs(unsigned int x)
{
int n;
asm volatile(
" ffs.f %0, %1 \n" /* 0:31; 31(Z) if src 0 */
" add.nz %0, %0, 1 \n" /* 0:31 -> 1:32 */
" mov.z %0, 0 \n" /* 31(Z)-> 0 */
: "=r"(n) /* Early clobber not needed */
: "r"(x)
: "cc");
return n;
}
/*
* __ffs: Similar to ffs, but zero based (0-31)
*/
static inline __attribute__ ((const)) unsigned long __ffs(unsigned long x)
{
unsigned long n;
asm volatile(
" ffs.f %0, %1 \n" /* 0:31; 31(Z) if src 0 */
" mov.z %0, 0 \n" /* 31(Z)-> 0 */
: "=r"(n)
: "r"(x)
: "cc");
return n;
}
#endif /* CONFIG_ISA_ARCOMPACT */
/*
* ffz = Find First Zero in word.
* @return:[0-31], 32 if all 1's
*/
#define ffz(x) __ffs(~(x))
#include <asm-generic/bitops/hweight.h>
#include <asm-generic/bitops/fls64.h>
#include <asm-generic/bitops/sched.h>
#include <asm-generic/bitops/lock.h>
#include <asm-generic/bitops/atomic.h>
#include <asm-generic/bitops/non-atomic.h>
#include <asm-generic/bitops/find.h>
#include <asm-generic/bitops/le.h>
#include <asm-generic/bitops/ext2-atomic-setbit.h>
#endif /* !__ASSEMBLY__ */
#endif
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