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MIPS: Clean up MIPSxx-optimized bitop functions 

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
hifive-unleashed-5.1
Ralf Baechle 2008-10-28 09:40:35 +00:00
parent c46b302b94
commit 4816227b54
1 changed files with 77 additions and 39 deletions
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116
arch/mips/include/asm/bitops.h
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@ -558,39 +558,67 @@ static inline void __clear_bit_unlock(unsigned long nr, volatile unsigned long *
__clear_bit(nr, addr);
}
#if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
/*
* Return the bit position (0..63) of the most significant 1 bit in a word
* Returns -1 if no 1 bit exists
*/
static inline unsigned long __fls(unsigned long x)
static inline unsigned long __fls(unsigned long word)
{
int lz;
int num;
if (sizeof(x) == 4) {
if (BITS_PER_LONG == 32 &&
__builtin_constant_p(cpu_has_mips_r) && cpu_has_mips_r) {
__asm__(
" .set push \n"
" .set mips32 \n"
" clz %0, %1 \n"
" .set pop \n"
: "=r" (lz)
: "r" (x));
: "=r" (num)
: "r" (word));
return 31 - lz;
return 31 - num;
}
BUG_ON(sizeof(x) != 8);
if (BITS_PER_LONG == 64 &&
__builtin_constant_p(cpu_has_mips64) && cpu_has_mips64) {
__asm__(
" .set push \n"
" .set mips64 \n"
" dclz %0, %1 \n"
" .set pop \n"
: "=r" (num)
: "r" (word));
__asm__(
" .set push \n"
" .set mips64 \n"
" dclz %0, %1 \n"
" .set pop \n"
: "=r" (lz)
: "r" (x));
return 63 - num;
}
return 63 - lz;
num = BITS_PER_LONG - 1;
#if BITS_PER_LONG == 64
if (!(word & (~0ul << 32))) {
num -= 32;
word <<= 32;
}
#endif
if (!(word & (~0ul << (BITS_PER_LONG-16)))) {
num -= 16;
word <<= 16;
}
if (!(word & (~0ul << (BITS_PER_LONG-8)))) {
num -= 8;
word <<= 8;
}
if (!(word & (~0ul << (BITS_PER_LONG-4)))) {
num -= 4;
word <<= 4;
}
if (!(word & (~0ul << (BITS_PER_LONG-2)))) {
num -= 2;
word <<= 2;
}
if (!(word & (~0ul << (BITS_PER_LONG-1))))
num -= 1;
return num;
}
/*
@ -612,23 +640,43 @@ static inline unsigned long __ffs(unsigned long word)
* This is defined the same way as ffs.
* Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
*/
static inline int fls(int word)
static inline int fls(int x)
{
__asm__("clz %0, %1" : "=r" (word) : "r" (word));
int r;
return 32 - word;
if (__builtin_constant_p(cpu_has_mips_r) && cpu_has_mips_r) {
__asm__("clz %0, %1" : "=r" (x) : "r" (x));
return 32 - x;
}
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)) {
x <<= 1;
r -= 1;
}
return r;
}
#if defined(CONFIG_64BIT) && defined(CONFIG_CPU_MIPS64)
static inline int fls64(__u64 word)
{
__asm__("dclz %0, %1" : "=r" (word) : "r" (word));
return 64 - word;
}
#else
#include <asm-generic/bitops/fls64.h>
#endif
/*
* ffs - find first bit set.
@ -646,16 +694,6 @@ static inline int ffs(int word)
return fls(word & -word);
}
#else
#include <asm-generic/bitops/__ffs.h>
#include <asm-generic/bitops/__fls.h>
#include <asm-generic/bitops/ffs.h>
#include <asm-generic/bitops/fls.h>
#include <asm-generic/bitops/fls64.h>
#endif /*defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64) */
#include <asm-generic/bitops/ffz.h>
#include <asm-generic/bitops/find.h>