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0ac5ae2335
libm is now somewhat integrated with gcc's -ffinite-math-only option and lots of the wrapper functions have been optimized.
27 lines
620 B
C
27 lines
620 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)
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{
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if (__builtin_expect (x <= u_threshold || x > o_threshold, 0)
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&& _LIB_VERSION != _IEEE_ && __finite (x))
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/* exp2 overflow: 44, exp2 underflow: 45 */
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return __kernel_standard (x, x, 44 + (x <= o_threshold));
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return __ieee754_exp2 (x);
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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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