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// SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
/* Copyright 2016 IBM Corp. */
#include "bitmap.h"
static int __bitmap_find_bit(bitmap_t map, unsigned int start, unsigned int count,
bool value)
{
unsigned int el, first_bit;
unsigned int end = start + count;
bitmap_elem_t e, ev;
int b;
ev = value ? -1ul : 0;
el = BITMAP_ELEM(start);
first_bit = BITMAP_BIT(start);
while (start < end) {
e = map[el] ^ ev;
e |= ((1ul << first_bit) - 1);
if (~e)
break;
start = (start + BITMAP_ELSZ) & ~(BITMAP_ELSZ - 1);
first_bit = 0;
el++;
}
for (b = first_bit; b < BITMAP_ELSZ && start < end; b++,start++) {
if ((e & (1ull << b)) == 0)
return start;
}
return -1;
}
int bitmap_find_zero_bit(bitmap_t map, unsigned int start, unsigned int count)
{
return __bitmap_find_bit(map, start, count, false);
}
int bitmap_find_one_bit(bitmap_t map, unsigned int start, unsigned int count)
{
return __bitmap_find_bit(map, start, count, true);
}
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