kaguya
31 lines
514 B
C
31 lines
514 B
C
#include <float.h>
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#include <math.h>
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#include <stdint.h>
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#if FLT_EVAL_METHOD==0
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#define EPS FLT_EPSILON
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#elif FLT_EVAL_METHOD==1
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#define EPS DBL_EPSILON
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#elif FLT_EVAL_METHOD==2
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#define EPS LDBL_EPSILON
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#endif
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static const float_t toint = 1/EPS;
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float rintf(float x)
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{
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union {float f; uint32_t i;} u = {x};
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int e = u.i>>23 & 0xff;
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int s = u.i>>31;
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float_t y;
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if (e >= 0x7f+23)
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return x;
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if (s)
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y = x - toint + toint;
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else
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y = x + toint - toint;
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if (y == 0)
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return s ? -0.0f : 0.0f;
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return y;
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}
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