------- Additional Comments From pinskia at gcc dot gnu dot org 2005-02-16
14:51 -------
Ok, this is the patch which caused this code generation regression:
2004-02-07 Roger Sayle <[EMAIL PROTECTED]>
* fold-const.c (negate_expr_p, negate_expr): Optimize -(A+B) into
either (-A)-B or (-B)-A, if A or B is easily negated respectively.
(fold) <MINUS_EXPR>: Optimize (A*C) - (B*C) -> (A-B)*C for both
integer types and floating point with unsafe_math_optimizations.
Add similar optimization for (A*C1) - (A*C2) -> A*(C1-C2).
Optimize A - B as A + (-B), if B is easily negated.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=19988
