forked from 0ad/0ad
27 lines
592 B
C++
27 lines
592 B
C++
/**
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* =========================================================================
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* File : bits.cpp
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* Project : 0 A.D.
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* Description : bit-twiddling.
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* =========================================================================
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*/
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// license: GPL; see lib/license.txt
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#include "precompiled.h"
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#include "bits.h"
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static inline u32 get_float_bits(const float x)
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{
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u32 ret;
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memcpy(&ret, &x, 4);
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return ret;
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}
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int floor_log2(const float x)
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{
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const u32 i = get_float_bits(x);
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const u32 biased_exp = (i >> 23) & 0xFF;
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return (int)biased_exp - 127;
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}
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