14 lines
352 B
C
14 lines
352 B
C
#ifndef _SQRT_DATA_H
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#define _SQRT_DATA_H
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#include <features.h>
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#include <stdint.h>
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/* if x in [1,2): i = (int)(64*x);
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if x in [2,4): i = (int)(32*x-64);
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__rsqrt_tab[i]*2^-16 is estimating 1/sqrt(x) with small relative error:
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|__rsqrt_tab[i]*0x1p-16*sqrt(x) - 1| < -0x1.fdp-9 < 2^-8 */
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extern hidden const uint16_t __rsqrt_tab[128];
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#endif
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