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Diffstat (limited to 'newlib/libm/common/s_scalbn.c')
-rw-r--r-- | newlib/libm/common/s_scalbn.c | 110 |
1 files changed, 0 insertions, 110 deletions
diff --git a/newlib/libm/common/s_scalbn.c b/newlib/libm/common/s_scalbn.c deleted file mode 100644 index 50f20efec..000000000 --- a/newlib/libm/common/s_scalbn.c +++ /dev/null @@ -1,110 +0,0 @@ - -/* @(#)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. - * ==================================================== - */ - -/* -FUNCTION -<<scalbn>>, <<scalbnf>>, <<scalbln>>, <<scalblnf>>--scale by power of FLT_RADIX (=2) -INDEX - scalbn -INDEX - scalbnf -INDEX - scalbln -INDEX - scalblnf - -ANSI_SYNOPSIS - #include <math.h> - double scalbn(double <[x]>, int <[n]>); - float scalbnf(float <[x]>, int <[n]>); - double scalbln(double <[x]>, long int <[n]>); - float scalblnf(float <[x]>, long int <[n]>); - -DESCRIPTION -The <<scalbn>> and <<scalbln>> functions compute - @ifnottex - <[x]> times FLT_RADIX to the power <[n]>. - @end ifnottex - @tex - $x \cdot FLT\_RADIX^n$. - @end tex -efficiently. The result is computed by manipulating the exponent, rather than -by actually performing an exponentiation or multiplication. In this -floating-point implementation FLT_RADIX=2, which makes the <<scalbn>> -functions equivalent to the <<ldexp>> functions. - -RETURNS -<[x]> times 2 to the power <[n]>. A range error may occur. - -PORTABILITY -ANSI C, POSIX - -SEEALSO -<<ldexp>> - -*/ - -/* - * 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 scalbn (double x, int n) -#else - double scalbn (x,n) - double x; 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 (n< -50000) return tiny*x; /*underflow*/ - } - if (k==0x7ff) return x+x; /* NaN or Inf */ - k = k+n; - if (k > 0x7fe) return huge*copysign(huge,x); /* overflow */ - if (k > 0) /* normal result */ - {SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20)); return x;} - if (k <= -54) { - if (n > 50000) /* in case integer overflow in n+k */ - return huge*copysign(huge,x); /*overflow*/ - else 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 */ |