freebsd-src/lib/msun
Bruce Evans 487ddb8fa4 Compute (1 - x^2) as ((1 - x) * (1 + x)) instead of as (1 - x * x) to
avoid easily avoidable loss of precision when |x| is nearly 1.

Extended (64-bit) precision only moves the meaning of "nearly" here.

This probably could be done better by splitting up the range into
|x| <= 0.5 and |x| > 0.5 like the C version.  However, ucbtest
does't report any errors in this version.  Perhaps the C version
should be used anyway.  It's only 25% slower now on a P5, provided
the C version of sqrt() isn't used, and the C version could be
optimized better.

Errors checked by:	ucbtest
1997-02-20 12:37:49 +00:00
..
bsdsrc Remove trailing whitespace. 1995-05-30 05:51:47 +00:00
i387 Compute (1 - x^2) as ((1 - x) * (1 + x)) instead of as (1 - x * x) to 1997-02-20 12:37:49 +00:00
man Sort cross references. 1997-01-20 23:23:22 +00:00
src Select between the generic math functions and the i387-specific ones 1997-02-16 18:26:31 +00:00
Makefile Select between the generic math functions and the i387-specific ones 1997-02-16 18:26:31 +00:00