30 lines
449 B
C
30 lines
449 B
C
#include "libm.h"
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double scalbn(double x, int n)
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{
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double scale;
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if (n > 1023) {
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x *= 0x1p1023;
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n -= 1023;
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if (n > 1023) {
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x *= 0x1p1023;
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n -= 1023;
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if (n > 1023)
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n = 1023;
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}
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} else if (n < -1022) {
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x *= 0x1p-1022;
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n += 1022;
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if (n < -1022) {
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x *= 0x1p-1022;
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n += 1022;
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if (n < -1022)
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n = -1022;
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}
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}
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INSERT_WORDS(scale, (uint32_t)(0x3ff+n)<<20, 0);
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STRICT_ASSIGN(double, x, x * scale);
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return x;
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}
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