kaguya
32 lines
477 B
C
32 lines
477 B
C
#include <math.h>
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#include <stdint.h>
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float scalbnf(float x, int n)
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{
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union {float f; uint32_t i;} u;
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float_t y = x;
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if (n > 127) {
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y *= 0x1p127f;
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n -= 127;
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if (n > 127) {
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y *= 0x1p127f;
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n -= 127;
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if (n > 127)
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n = 127;
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}
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} else if (n < -126) {
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y *= 0x1p-126f * 0x1p24f;
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n += 126 - 24;
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if (n < -126) {
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y *= 0x1p-126f * 0x1p24f;
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n += 126 - 24;
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if (n < -126)
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n = -126;
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}
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}
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u.i = (uint32_t)(0x7f+n)<<23;
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x = y * u.f;
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return x;
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}
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