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bits.h: move popcount32() up

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This commit is contained in:
Bruno Raoult
2022-12-06 14:43:16 +01:00
parent 50919df627
commit 2c14abff21
1 changed files with 21 additions and 21 deletions
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42
2020/include/bits.h
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@@ -75,6 +75,27 @@ static __always_inline int popcount64(u64 n)
# endif # endif
} }
static __always_inline int popcount32(u32 n)
{
# if __has_builtin(__builtin_popcount)
# ifdef DEBUG_BITS
log_f(1, "builtin.\n");
# endif
return __builtin_popcount(n);
# else
# ifdef DEBUG_BITS
log_f(1, "emulated.\n");
# endif
int count = 0;
while (n) {
count++;
n &= (n - 1);
}
return count;
# endif
}
/* char is a special case, as it can be signed or unsigned /* char is a special case, as it can be signed or unsigned
*/ */
typedef signed char schar; typedef signed char schar;
@@ -244,27 +265,6 @@ static __always_inline uint ffs32(u32 n)
# endif # endif
} }
static __always_inline int popcount32(u32 n)
{
# if __has_builtin(__builtin_popcount)
# ifdef DEBUG_BITS
log_f(1, "builtin.\n");
# endif
return __builtin_popcount(n);
# else
# ifdef DEBUG_BITS
log_f(1, "emulated.\n");
# endif
int count = 0;
while (n) {
count++;
n &= (n - 1);
}
return count;
# endif
}
/* rolXX are taken from kernel's <linux/bitops.h> are are: /* rolXX are taken from kernel's <linux/bitops.h> are are:
* SPDX-License-Identifier: GPL-2.0 * SPDX-License-Identifier: GPL-2.0
*/ */