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author | Thomas Fitzsimmons <fitzsim@redhat.com> | 2002-06-07 21:59:57 +0000 |
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committer | Thomas Fitzsimmons <fitzsim@redhat.com> | 2002-06-07 21:59:57 +0000 |
commit | 0953fe640f177b565578ed7ecc77169ec1a914fa (patch) | |
tree | f63c2a55e4d0e5a067da91cea95ae88a7c15af7e /newlib/libm/common/s_scalbln.c | |
parent | 2bd6505b3991588a15c865618e1edb76d4a6373c (diff) | |
download | cygnal-0953fe640f177b565578ed7ecc77169ec1a914fa.tar.gz cygnal-0953fe640f177b565578ed7ecc77169ec1a914fa.tar.bz2 cygnal-0953fe640f177b565578ed7ecc77169ec1a914fa.zip |
* libm/common/s_fdim.c: New file.
* libm/common/s_fma.c: Likewise.
* libm/common/s_fmax.c: Likewise.
* libm/common/s_fmin.c: Likewise.
* libm/common/s_fpclassify.c: Likewise.
* libm/common/s_lrint.c: Likewise.
* libm/common/s_lround.c: Likewise.
* libm/common/s_nearbyint.c: Likewise.
* libm/common/s_remquo.c: Likewise.
* libm/common/s_round.c: Likewise.
* libm/common/s_scalbln.c: Likewise.
* libm/common/s_signbit.c: Likewise.
* libm/common/s_trunc.c: Likewise.
* libm/common/sf_fdim.c: Likewise.
* libm/common/sf_fma.c: Likewise.
* libm/common/sf_fmax.c: Likewise.
* libm/common/sf_fmin.c: Likewise.
* libm/common/sf_lrint.c: Likewise.
* libm/common/sf_lround.c: Likewise.
* libm/common/sf_nearbyint.c: Likewise.
* libm/common/sf_remquo.c: Likewise.
* libm/common/sf_round.c: Likewise.
* libm/common/sf_scalbln.c: Likewise.
* libm/common/sf_trunc.c: Likewise.
* libm/math/w_exp2.c: Likewise.
* libm/math/w_tgamma.c: Likewise.
* libm/math/wf_exp2.c: Likewise.
* libm/math/wf_tgamma.c: Likewise.
* libm/mathfp/s_exp2.c: Likewise.
* libm/mathfp/s_tgamma.c: Likewise.
* libm/mathfp/sf_exp2.c: Likewise.
* libm/mathfp/sf_tgamma.c: Likewise.
* libm/math/er_gamma.c: Fix return value.
* libm/math/erf_gamma.c: Likewise.
* libm/mathfp/er_gamma.c: Likewise.
* libm/mathfp/erf_gamma.c: Likewise.
* libc/include/math.h (!__STRICT_ANSI__): Include ISOC99-specific
declarations and macros.
Regenerated all Makefile.in, aclocal.m4 and configure files to
use new libtool macros in top-level libtool.m4
Diffstat (limited to 'newlib/libm/common/s_scalbln.c')
-rw-r--r-- | newlib/libm/common/s_scalbln.c | 64 |
1 files changed, 64 insertions, 0 deletions
diff --git a/newlib/libm/common/s_scalbln.c b/newlib/libm/common/s_scalbln.c new file mode 100644 index 000000000..5af9d89e7 --- /dev/null +++ b/newlib/libm/common/s_scalbln.c @@ -0,0 +1,64 @@ +/* @(#)s_scalbn.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. + * ==================================================== + */ + +/* + * scalbn (double x, int n) + * scalbn(x,n) returns x* 2**n computed by exponent + * manipulation rather than by actually performing an + * exponentiation or a multiplication. + */ + +#include "fdlibm.h" + +#ifndef _DOUBLE_IS_32BITS + +#ifdef __STDC__ +static const double +#else +static double +#endif +two54 = 1.80143985094819840000e+16, /* 0x43500000, 0x00000000 */ +twom54 = 5.55111512312578270212e-17, /* 0x3C900000, 0x00000000 */ +huge = 1.0e+300, +tiny = 1.0e-300; + +#ifdef __STDC__ + double scalbln (double x, long int n) +#else + double scalbln (x,n) + double x; long int n; +#endif +{ + __int32_t k,hx,lx; + EXTRACT_WORDS(hx,lx,x); + k = (hx&0x7ff00000)>>20; /* extract exponent */ + if (k==0) { /* 0 or subnormal x */ + if ((lx|(hx&0x7fffffff))==0) return x; /* +-0 */ + x *= two54; + GET_HIGH_WORD(hx,x); + k = ((hx&0x7ff00000)>>20) - 54; + } + if (k==0x7ff) return x+x; /* NaN or Inf */ + k = k+n; + if (n> 50000 || k > 0x7fe) + return huge*copysign(huge,x); /* overflow */ + if (n< -50000) return tiny*copysign(tiny,x); /*underflow*/ + if (k > 0) /* normal result */ + {SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20)); return x;} + if (k <= -54) + return tiny*copysign(tiny,x); /*underflow*/ + k += 54; /* subnormal result */ + SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20)); + return x*twom54; +} + +#endif /* _DOUBLE_IS_32BITS */ |