29 lines
411 B
C++
29 lines
411 B
C++
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/* Copyright (C) Teemu Suutari */
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#include "Common.hpp"
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namespace ancient::internal
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{
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uint32_t rotateBits(uint32_t value,uint32_t count)
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{
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static const uint8_t rotateNibble[16]={
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0x0,0x8,0x4,0xc,
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0x2,0xa,0x6,0xe,
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0x1,0x9,0x5,0xd,
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0x3,0xb,0x7,0xf
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};
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uint32_t ret=0;
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for (uint32_t i=0;i<count;i+=4)
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{
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ret=(ret<<4)|rotateNibble[value&0xf];
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value>>=4;
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}
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ret>>=(4-count)&3;
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return ret;
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}
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}
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