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31 lines
537 B
C
31 lines
537 B
C
/*
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* wrapper log2(X)
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*/
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#include <math.h>
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#include "math_private.h"
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float
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__log2f (float x) /* wrapper log2f */
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{
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#ifdef _IEEE_LIBM
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return __ieee754_log2f (x);
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#else
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float z;
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z = __ieee754_log2f (x);
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if (_LIB_VERSION == _IEEE_ || __isnanf (x)) return z;
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if (x <= 0.0f)
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{
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if (x == 0.0f)
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/* log2f (0) */
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return __kernel_standard ((double) x, (double) x, 148);
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else
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/* log2f (x < 0) */
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return __kernel_standard ((double) x, (double) x, 149);
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}
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else
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return z;
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#endif
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}
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weak_alias (__log2f, log2f)
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