mirror of
https://github.com/dbalsom/x86_microcode.git
synced 2026-06-09 13:04:17 +03:00
Andrew Jenner
35 lines
572 B
C
35 lines
572 B
C
#include "alfe/main.h"
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#ifndef INCLUDED_BITWISE_H
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#define INCLUDED_BITWISE_H
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#ifdef _MSC_VER
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#include <intrin.h>
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#endif
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int roundUpToPowerOf2(int n)
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{
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#ifdef _MSC_VER
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unsigned long k;
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_BitScanReverse(&k, n);
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if ((n & (n - 1)) != 0)
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++k;
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return 1 << k;
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#elif defined __GNUC__
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int k = (sizeof(int)*8 - 1) - __builtin_clz(n);
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if ((n & (n - 1)) != 0)
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++k;
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return 1 << k;
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#else
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--n;
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n |= n >> 1;
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n |= n >> 2;
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n |= n >> 4;
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n |= n >> 8;
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n |= n >> 16;
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return n + 1;
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#endif
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}
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#endif // INCLUDED_BITWISE_H
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