* flow.c (ior_reg_cond): Return NULL if ! add and rtx wasn't optimized.
Return correct value if one of the subexpressions was optimized to
0 resp. 1. Optimize (x | A) | x and (x & A) | x.
(and_reg_cond): Similarly.
* gcc.c-torture/compile/20011130-2.c: New test.
From-SVN: r47602
