33 lines
767 B
C
33 lines
767 B
C
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/* Copyright (c) 2017 SiFive Inc. All rights reserved.
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This copyrighted material is made available to anyone wishing to use,
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modify, copy, or redistribute it subject to the terms and conditions
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of the BSD License. This program is distributed in the hope that
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it will be useful, but WITHOUT ANY WARRANTY expressed or implied,
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including the implied warranties of MERCHANTABILITY or FITNESS FOR
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A PARTICULAR PURPOSE. A copy of this license is available at
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http://www.opensource.org/licenses.
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*/
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#include <strings.h>
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int
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ffs (int word)
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{
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#if __riscv_xlen == 32
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return (__builtin_ffs (word));
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#else
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int i;
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if (!word)
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return 0;
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i = 0;
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for (;;)
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{
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if (((1 << i++) & word) != 0)
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return i;
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}
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return 0;
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#endif
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}
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