35 lines
552 B
C
35 lines
552 B
C
#include "libc/math/libm.h"
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float modff(float x, float *iptr)
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{
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union {float f; uint32_t i;} u = {x};
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uint32_t mask;
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int e = (int)(u.i>>23 & 0xff) - 0x7f;
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/* no fractional part */
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if (e >= 23) {
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*iptr = x;
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if (e == 0x80 && u.i<<9 != 0) { /* nan */
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return x;
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}
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u.i &= 0x80000000;
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return u.f;
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}
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/* no integral part */
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if (e < 0) {
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u.i &= 0x80000000;
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*iptr = u.f;
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return x;
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}
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mask = 0x007fffff>>e;
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if ((u.i & mask) == 0) {
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*iptr = x;
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u.i &= 0x80000000;
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return u.f;
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}
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u.i &= ~mask;
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*iptr = u.f;
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return x - u.f;
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}
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