diff options
Diffstat (limited to 'REORG.TODO/sysdeps/ieee754/dbl-64/wordsize-64/s_modf.c')
| -rw-r--r-- | REORG.TODO/sysdeps/ieee754/dbl-64/wordsize-64/s_modf.c | 66 |
1 files changed, 66 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/ieee754/dbl-64/wordsize-64/s_modf.c b/REORG.TODO/sysdeps/ieee754/dbl-64/wordsize-64/s_modf.c new file mode 100644 index 0000000000..c309e56272 --- /dev/null +++ b/REORG.TODO/sysdeps/ieee754/dbl-64/wordsize-64/s_modf.c @@ -0,0 +1,66 @@ +/* Rewritten for 64-bit machines by Ulrich Drepper <drepper@gmail.com>. */ +/* + * ==================================================== + * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. + * + * Developed at SunPro, a Sun Microsystems, Inc. business. + * Permission to use, copy, modify, and distribute this + * software is freely granted, provided that this notice + * is preserved. + * ==================================================== + */ + +/* + * modf(double x, double *iptr) + * return fraction part of x, and return x's integral part in *iptr. + * Method: + * Bit twiddling. + * + * Exception: + * No exception. + */ + +#include <math.h> +#include <math_private.h> +#include <stdint.h> + +static const double one = 1.0; + +double +__modf(double x, double *iptr) +{ + int64_t i0; + int32_t j0; + EXTRACT_WORDS64(i0,x); + j0 = ((i0>>52)&0x7ff)-0x3ff; /* exponent of x */ + if(j0<52) { /* integer part in x */ + if(j0<0) { /* |x|<1 */ + /* *iptr = +-0 */ + INSERT_WORDS64(*iptr,i0&UINT64_C(0x8000000000000000)); + return x; + } else { + uint64_t i = UINT64_C(0x000fffffffffffff)>>j0; + if((i0&i)==0) { /* x is integral */ + *iptr = x; + /* return +-0 */ + INSERT_WORDS64(x,i0&UINT64_C(0x8000000000000000)); + return x; + } else { + INSERT_WORDS64(*iptr,i0&(~i)); + return x - *iptr; + } + } + } else { /* no fraction part */ + *iptr = x*one; + /* We must handle NaNs separately. */ + if (j0 == 0x400 && (i0 & UINT64_C(0xfffffffffffff))) + return x*one; + INSERT_WORDS64(x,i0&UINT64_C(0x8000000000000000)); /* return +-0 */ + return x; + } +} +weak_alias (__modf, modf) +#ifdef NO_LONG_DOUBLE +strong_alias (__modf, __modfl) +weak_alias (__modf, modfl) +#endif |