22 lines
635 B
C
22 lines
635 B
C
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#include <fenv.h>
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#include <math.h>
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#include <errno.h>
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#define FE_ROUNDING_MASK \
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(FE_TONEAREST | FE_DOWNWARD | FE_UPWARD | FE_TOWARDZERO)
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long double
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modfl (long double value, long double* iptr)
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{
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long double int_part;
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unsigned short saved_cw;
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/* truncate */
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asm ("fnstcw %0;" : "=m" (saved_cw)); /* save control word */
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asm ("fldcw %0;" : : "m" ((saved_cw & ~FE_ROUNDING_MASK)
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| FE_TOWARDZERO));
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asm ("frndint;" : "=t" (int_part) : "0" (value)); /* round */
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asm ("fldcw %0;" : : "m" (saved_cw)); /* restore saved cw */
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if (iptr)
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*iptr = int_part;
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return (isinf (value) ? 0.0L : value - int_part);
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}
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