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33 lines
576 B
C
33 lines
576 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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double
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__log2 (double x) /* wrapper log2 */
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{
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#ifdef _IEEE_LIBM
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return __ieee754_log2 (x);
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#else
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double z;
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z = __ieee754_log2 (x);
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if (_LIB_VERSION == _IEEE_ || __isnan (x)) return z;
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if (x <= 0.0)
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{
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if (x == 0.0)
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return __kernel_standard (x, x, 48); /* log2 (0) */
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else
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return __kernel_standard (x, x, 49); /* log2 (x < 0) */
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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 (__log2, log2)
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#ifdef NO_LONG_DOUBLE
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strong_alias (__log2, __log2l)
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weak_alias (__log2, log2l)
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#endif
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