diff options
Diffstat (limited to 'REORG.TODO/sysdeps/ieee754/ldbl-128ibm/e_sinhl.c')
-rw-r--r-- | REORG.TODO/sysdeps/ieee754/ldbl-128ibm/e_sinhl.c | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/ieee754/ldbl-128ibm/e_sinhl.c b/REORG.TODO/sysdeps/ieee754/ldbl-128ibm/e_sinhl.c new file mode 100644 index 0000000000..67d9d24ce7 --- /dev/null +++ b/REORG.TODO/sysdeps/ieee754/ldbl-128ibm/e_sinhl.c @@ -0,0 +1,79 @@ +/* + * ==================================================== + * 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. + * ==================================================== + */ + + +/* __ieee754_sinh(x) + * Method : + * mathematically sinh(x) if defined to be (exp(x)-exp(-x))/2 + * 1. Replace x by |x| (sinh(-x) = -sinh(x)). + * 2. + * E + E/(E+1) + * 0 <= x <= 40 : sinh(x) := --------------, E=expm1(x) + * 2 + * + * 40 <= x <= lnovft : sinh(x) := exp(x)/2 + * lnovft <= x <= ln2ovft: sinh(x) := exp(x/2)/2 * exp(x/2) + * ln2ovft < x : sinh(x) := x*shuge (overflow) + * + * Special cases: + * sinh(x) is |x| if x is +INF, -INF, or NaN. + * only sinh(0)=0 is exact for finite x. + */ + +#include <float.h> +#include <math.h> +#include <math_private.h> + +static const long double one = 1.0, shuge = 1.0e307; + +long double +__ieee754_sinhl(long double x) +{ + long double t,w,h; + int64_t ix,jx; + double xhi; + + /* High word of |x|. */ + xhi = ldbl_high (x); + EXTRACT_WORDS64 (jx, xhi); + ix = jx&0x7fffffffffffffffLL; + + /* x is INF or NaN */ + if(ix>=0x7ff0000000000000LL) return x+x; + + h = 0.5; + if (jx<0) h = -h; + /* |x| in [0,40], return sign(x)*0.5*(E+E/(E+1))) */ + if (ix < 0x4044000000000000LL) { /* |x|<40 */ + if (ix<0x3c90000000000000LL) { /* |x|<2**-54 */ + math_check_force_underflow (x); + if(shuge+x>one) return x;/* sinhl(tiny) = tiny with inexact */ + } + t = __expm1l(fabsl(x)); + if(ix<0x3ff0000000000000LL) return h*(2.0*t-t*t/(t+one)); + w = t/(t+one); + return h*(t+w); + } + + /* |x| in [40, log(maxdouble)] return 0.5*exp(|x|) */ + if (ix < 0x40862e42fefa39efLL) return h*__ieee754_expl(fabsl(x)); + + /* |x| in [log(maxdouble), overflowthresold] */ + if (ix <= 0x408633ce8fb9f87eLL) { + w = __ieee754_expl(0.5*fabsl(x)); + t = h*w; + return t*w; + } + + /* |x| > overflowthresold, sinh(x) overflow */ + return x*shuge; +} +strong_alias (__ieee754_sinhl, __sinhl_finite) |