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37 lines
732 B
C
37 lines
732 B
C
/*
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* wrapper exp2(x)
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*/
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#include <float.h>
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#include <math.h>
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#include "math_private.h"
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static const double o_threshold= (double) DBL_MAX_EXP;
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static const double u_threshold= (double) (DBL_MIN_EXP - DBL_MANT_DIG - 1);
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double
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__exp2 (double x) /* wrapper exp2 */
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{
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#ifdef _IEEE_LIBM
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return __ieee754_exp2 (x);
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#else
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double z;
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z = __ieee754_exp2 (x);
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if (_LIB_VERSION != _IEEE_ && __finite (x))
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{
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if (x > o_threshold)
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/* exp2 overflow */
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return __kernel_standard (x, x, 44);
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else if (x <= u_threshold)
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/* exp2 underflow */
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return __kernel_standard (x, x, 45);
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}
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return z;
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#endif
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}
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weak_alias (__exp2, exp2)
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#ifdef NO_LONG_DOUBLE
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strong_alias (__exp2, __exp2l)
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weak_alias (__exp2, exp2l)
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#endif
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