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+/* Integer base 2 logarithm calculation
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+ *
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+ * Copyright (C) 2006 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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+#ifndef _TOOLS_LINUX_LOG2_H
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+#define _TOOLS_LINUX_LOG2_H
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+
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+/*
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+ * Determine whether some value is a power of two, where zero is
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+ * *not* considered a power of two.
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+ */
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+
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+static inline __attribute__((const))
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+bool is_power_of_2(unsigned long n)
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+{
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+ return (n != 0 && ((n & (n - 1)) == 0));
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+}
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+
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+#endif /* _TOOLS_LINUX_LOG2_H */
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