26 lines
646 B
C++
26 lines
646 B
C++
#ifndef __CXXMPH_MPH_BITS_H__
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#define __CXXMPH_MPH_BITS_H__
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#include <stdint.h> // for uint32_t and friends
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#include <climits>
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namespace cxxmph {
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static const uint8_t valuemask[] = { 0xfc, 0xf3, 0xcf, 0x3f};
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static void set_2bit_value(uint8_t *d, uint32_t i, uint8_t v) {
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d[(i >> 2)] &= ((v << ((i & 3) << 1)) | valuemask[i & 3]);
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}
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static uint32_t get_2bit_value(const uint8_t* d, uint32_t i) {
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return (d[(i >> 2)] >> (((i & 3) << 1)) & 3);
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}
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static uint32_t nextpoweroftwo(uint32_t k) {
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if (k == 0) return 1;
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k--;
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for (int i=1; i<sizeof(uint32_t)*CHAR_BIT; i<<=1) k = k | k >> i;
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return k+1;
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}
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} // namespace cxxmph
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#endif
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