For small arguments, these functions use simple approximations,

e.g. cos(small) = 1, sin(small) = small.  This commit tightens
the thresholds at which the simple approximations are used.

Reviewed by:	bde
This commit is contained in:
David Schultz 2011-02-10 07:37:50 +00:00
parent b775d18789
commit e044d80d08
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=218509
5 changed files with 5 additions and 5 deletions

View File

@ -82,7 +82,7 @@ __ieee754_asin(double x)
return x*pio2_hi+x*pio2_lo;
return (x-x)/(x-x); /* asin(|x|>1) is NaN */
} else if (ix<0x3fe00000) { /* |x|<0.5 */
if(ix<0x3e400000) { /* if |x| < 2**-27 */
if(ix<0x3e500000) { /* if |x| < 2**-26 */
if(huge+x>one) return x;/* return x with inexact if x!=0*/
}
t = x*x;

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@ -87,7 +87,7 @@ atan(double x)
if(hx>0) return atanhi[3]+*(volatile double *)&atanlo[3];
else return -atanhi[3]-*(volatile double *)&atanlo[3];
} if (ix < 0x3fdc0000) { /* |x| < 0.4375 */
if (ix < 0x3e200000) { /* |x| < 2^-29 */
if (ix < 0x3e400000) { /* |x| < 2^-27 */
if(huge+x>one) return x; /* raise inexact */
}
id = -1;

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@ -63,7 +63,7 @@ cos(double x)
/* |x| ~< pi/4 */
ix &= 0x7fffffff;
if(ix <= 0x3fe921fb) {
if(ix<0x3e400000) /* if x < 2**-27 */
if(ix<0x3e46a09e) /* if x < 2**-27 * sqrt(2) */
if(((int)x)==0) return 1.0; /* generate inexact */
return __kernel_cos(x,z);
}

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@ -63,7 +63,7 @@ sin(double x)
/* |x| ~< pi/4 */
ix &= 0x7fffffff;
if(ix <= 0x3fe921fb) {
if(ix<0x3e400000) /* |x| < 2**-27 */
if(ix<0x3e500000) /* |x| < 2**-26 */
{if((int)x==0) return x;} /* generate inexact */
return __kernel_sin(x,z,0);
}

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@ -62,7 +62,7 @@ tan(double x)
/* |x| ~< pi/4 */
ix &= 0x7fffffff;
if(ix <= 0x3fe921fb) {
if(ix<0x3e300000) /* x < 2**-28 */
if(ix<0x3e400000) /* x < 2**-27 */
if((int)x==0) return x; /* generate inexact */
return __kernel_tan(x,z,1);
}