33 lines
431 B
C
33 lines
431 B
C
/*
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FUNCTION
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<<ffs>>---find first bit set in a word
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INDEX
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ffs
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SYNOPSIS
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#include <strings.h>
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int ffs(int <[word]>);
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DESCRIPTION
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<<ffs>> returns the first bit set in a word.
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RETURNS
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<<ffs>> returns 0 if <[c]> is 0, 1 if <[c]> is odd, 2 if <[c]> is a multiple of
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2, etc.
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PORTABILITY
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<<ffs>> is not ANSI C.
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No supporting OS subroutines are required. */
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#include <strings.h>
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int
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ffs(int i)
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{
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return (__builtin_ffs(i));
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}
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