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+/* find_next_bit.c: fallback find next bit implementation
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+ *
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+ * Copied from lib/find_next_bit.c to tools/lib/next_bit.c
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+ *
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+ * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
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+ * Written by David Howells (dhowells@redhat.com)
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+ *
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+ * This program is free software; you can redistribute it and/or
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+ * modify it under the terms of the GNU General Public License
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+ * as published by the Free Software Foundation; either version
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+ * 2 of the License, or (at your option) any later version.
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+ */
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+
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+#include <linux/bitops.h>
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+#include <asm/types.h>
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+#include <asm/byteorder.h>
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+
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+#define BITOP_WORD(nr) ((nr) / BITS_PER_LONG)
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+
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+#ifndef find_next_bit
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+/*
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+ * Find the next set bit in a memory region.
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+ */
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+unsigned long find_next_bit(const unsigned long *addr, unsigned long size,
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+ unsigned long offset)
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+{
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+ const unsigned long *p = addr + BITOP_WORD(offset);
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+ unsigned long result = offset & ~(BITS_PER_LONG-1);
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+ unsigned long tmp;
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+
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+ if (offset >= size)
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+ return size;
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+ size -= result;
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+ offset %= BITS_PER_LONG;
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+ if (offset) {
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+ tmp = *(p++);
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+ tmp &= (~0UL << offset);
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+ if (size < BITS_PER_LONG)
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+ goto found_first;
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+ if (tmp)
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+ goto found_middle;
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+ size -= BITS_PER_LONG;
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+ result += BITS_PER_LONG;
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+ }
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+ while (size & ~(BITS_PER_LONG-1)) {
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+ if ((tmp = *(p++)))
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+ goto found_middle;
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+ result += BITS_PER_LONG;
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+ size -= BITS_PER_LONG;
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+ }
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+ if (!size)
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+ return result;
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+ tmp = *p;
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+
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+found_first:
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+ tmp &= (~0UL >> (BITS_PER_LONG - size));
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+ if (tmp == 0UL) /* Are any bits set? */
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+ return result + size; /* Nope. */
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+found_middle:
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+ return result + __ffs(tmp);
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+}
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+#endif
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+
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+#ifndef find_first_bit
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+/*
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+ * Find the first set bit in a memory region.
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+ */
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+unsigned long find_first_bit(const unsigned long *addr, unsigned long size)
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+{
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+ const unsigned long *p = addr;
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+ unsigned long result = 0;
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+ unsigned long tmp;
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+
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+ while (size & ~(BITS_PER_LONG-1)) {
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+ if ((tmp = *(p++)))
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+ goto found;
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+ result += BITS_PER_LONG;
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+ size -= BITS_PER_LONG;
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+ }
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+ if (!size)
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+ return result;
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+
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+ tmp = (*p) & (~0UL >> (BITS_PER_LONG - size));
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+ if (tmp == 0UL) /* Are any bits set? */
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+ return result + size; /* Nope. */
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+found:
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+ return result + __ffs(tmp);
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+}
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+#endif
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