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1 /* ffs -- Find the first bit set in the parameter
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2
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3 @deftypefn Supplemental int ffs (int @var{valu})
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4
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5 Find the first (least significant) bit set in @var{valu}. Bits are
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6 numbered from right to left, starting with bit 1 (corresponding to the
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7 value 1). If @var{valu} is zero, zero is returned.
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8
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9 @end deftypefn
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10
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11 */
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12
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13 int
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14 ffs (register int valu)
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15 {
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16 register int bit;
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17
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18 if (valu == 0)
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19 return 0;
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20
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21 for (bit = 1; !(valu & 1); bit++)
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22 valu >>= 1;
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23
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24 return bit;
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25 }
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26
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