diff options
Diffstat (limited to 'REORG.TODO/sysdeps/ieee754/dbl-64/s_frexp.c')
| -rw-r--r-- | REORG.TODO/sysdeps/ieee754/dbl-64/s_frexp.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/ieee754/dbl-64/s_frexp.c b/REORG.TODO/sysdeps/ieee754/dbl-64/s_frexp.c new file mode 100644 index 0000000000..874214ec7c --- /dev/null +++ b/REORG.TODO/sysdeps/ieee754/dbl-64/s_frexp.c @@ -0,0 +1,58 @@ +/* @(#)s_frexp.c 5.1 93/09/24 */ +/* + * ==================================================== + * 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. + * ==================================================== + */ + +#if defined(LIBM_SCCS) && !defined(lint) +static char rcsid[] = "$NetBSD: s_frexp.c,v 1.9 1995/05/10 20:47:24 jtc Exp $"; +#endif + +/* + * for non-zero x + * x = frexp(arg,&exp); + * return a double fp quantity x such that 0.5 <= |x| <1.0 + * and the corresponding binary exponent "exp". That is + * arg = x*2^exp. + * If arg is inf, 0.0, or NaN, then frexp(arg,&exp) returns arg + * with *exp=0. + */ + +#include <math.h> +#include <math_private.h> + +static const double + two54 = 1.80143985094819840000e+16; /* 0x43500000, 0x00000000 */ + +double +__frexp (double x, int *eptr) +{ + int32_t hx, ix, lx; + EXTRACT_WORDS (hx, lx, x); + ix = 0x7fffffff & hx; + *eptr = 0; + if (ix >= 0x7ff00000 || ((ix | lx) == 0)) + return x + x; /* 0,inf,nan */ + if (ix < 0x00100000) /* subnormal */ + { + x *= two54; + GET_HIGH_WORD (hx, x); + ix = hx & 0x7fffffff; + *eptr = -54; + } + *eptr += (ix >> 20) - 1022; + hx = (hx & 0x800fffff) | 0x3fe00000; + SET_HIGH_WORD (x, hx); + return x; +} +weak_alias (__frexp, frexp) +#ifdef NO_LONG_DOUBLE +strong_alias (__frexp, __frexpl) +weak_alias (__frexp, frexpl) +#endif |