27 lines
465 B
C
27 lines
465 B
C
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/* ffs -- Find the first bit set in the parameter
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@deftypefn Supplemental int ffs (int @var{valu})
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Find the first (least significant) bit set in @var{valu}. Bits are
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numbered from right to left, starting with bit 1 (corresponding to the
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value 1). If @var{valu} is zero, zero is returned.
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@end deftypefn
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*/
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int
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ffs (register int valu)
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{
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register int bit;
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if (valu == 0)
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return 0;
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for (bit = 1; !(valu & 1); bit++)
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valu >>= 1;
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return bit;
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}
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