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https://github.com/fluencelabs/musl
synced 2025-05-29 07:31:53 +00:00
8051e08e10
The old scalbn.c was wrong and slow, the new one is just slow. (scalbn(0x1p+1023,-2097) should give 0x1p-1074, but the old code gave 0)
29 lines
427 B
C
29 lines
427 B
C
#include "libm.h"
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float scalbnf(float x, int n)
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{
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float scale;
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if (n > 127) {
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x *= 0x1p127f;
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n -= 127;
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if (n > 127) {
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x *= 0x1p127f;
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n -= 127;
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if (n > 127)
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return x * 0x1p127f;
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}
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} else if (n < -126) {
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x *= 0x1p-126f;
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n += 126;
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if (n < -126) {
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x *= 0x1p-126f;
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n += 126;
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if (n < -126)
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return x * 0x1p-126f;
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}
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}
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SET_FLOAT_WORD(scale, (uint32_t)(0x7f+n)<<23);
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return x * scale;
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}
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