diff options
Diffstat (limited to 'sysdeps/ieee754/dbl-64/e_cosh.c')
| -rw-r--r-- | sysdeps/ieee754/dbl-64/e_cosh.c | 72 |
1 files changed, 39 insertions, 33 deletions
diff --git a/sysdeps/ieee754/dbl-64/e_cosh.c b/sysdeps/ieee754/dbl-64/e_cosh.c index 229d5a2fb3..6caf943ed0 100644 --- a/sysdeps/ieee754/dbl-64/e_cosh.c +++ b/sysdeps/ieee754/dbl-64/e_cosh.c @@ -34,49 +34,55 @@ #include <math.h> #include <math_private.h> -static const double one = 1.0, half=0.5, huge = 1.0e300; +static const double one = 1.0, half = 0.5, huge = 1.0e300; double __ieee754_cosh (double x) { - double t,w; - int32_t ix; - u_int32_t lx; + double t, w; + int32_t ix; + u_int32_t lx; - /* High word of |x|. */ - GET_HIGH_WORD(ix,x); - ix &= 0x7fffffff; + /* High word of |x|. */ + GET_HIGH_WORD (ix, x); + ix &= 0x7fffffff; - /* |x| in [0,22] */ - if (ix < 0x40360000) { - /* |x| in [0,0.5*ln2], return 1+expm1(|x|)^2/(2*exp(|x|)) */ - if(ix<0x3fd62e43) { - t = __expm1(fabs(x)); - w = one+t; - if (ix<0x3c800000) return w; /* cosh(tiny) = 1 */ - return one+(t*t)/(w+w); - } - - /* |x| in [0.5*ln2,22], return (exp(|x|)+1/exp(|x|)/2; */ - t = __ieee754_exp(fabs(x)); - return half*t+half/t; + /* |x| in [0,22] */ + if (ix < 0x40360000) + { + /* |x| in [0,0.5*ln2], return 1+expm1(|x|)^2/(2*exp(|x|)) */ + if (ix < 0x3fd62e43) + { + t = __expm1 (fabs (x)); + w = one + t; + if (ix < 0x3c800000) + return w; /* cosh(tiny) = 1 */ + return one + (t * t) / (w + w); } - /* |x| in [22, log(maxdouble)] return half*exp(|x|) */ - if (ix < 0x40862e42) return half*__ieee754_exp(fabs(x)); + /* |x| in [0.5*ln2,22], return (exp(|x|)+1/exp(|x|)/2; */ + t = __ieee754_exp (fabs (x)); + return half * t + half / t; + } - /* |x| in [log(maxdouble), overflowthresold] */ - GET_LOW_WORD(lx,x); - if (ix<0x408633ce || ((ix==0x408633ce)&&(lx<=(u_int32_t)0x8fb9f87d))) { - w = __ieee754_exp(half*fabs(x)); - t = half*w; - return t*w; - } + /* |x| in [22, log(maxdouble)] return half*exp(|x|) */ + if (ix < 0x40862e42) + return half * __ieee754_exp (fabs (x)); + + /* |x| in [log(maxdouble), overflowthresold] */ + GET_LOW_WORD (lx, x); + if (ix < 0x408633ce || ((ix == 0x408633ce) && (lx <= (u_int32_t) 0x8fb9f87d))) + { + w = __ieee754_exp (half * fabs (x)); + t = half * w; + return t * w; + } - /* x is INF or NaN */ - if(ix>=0x7ff00000) return x*x; + /* x is INF or NaN */ + if (ix >= 0x7ff00000) + return x * x; - /* |x| > overflowthresold, cosh(x) overflow */ - return huge*huge; + /* |x| > overflowthresold, cosh(x) overflow */ + return huge * huge; } strong_alias (__ieee754_cosh, __cosh_finite) |