PR middle-end/23670
* fold-const.c (fold_binary) <BIT_IOR_EXPR>: Optimize (X&Y)|Y into
(X,Y) and the corresponding symmetry related transformations.
(fold_binary) <BIT_AND_EXPR>: Likewise, optimize (X|Y)&Y into
(X,Y) and its symmetry related transformations.
* gcc.dg/tree-ssa/andor-2.c: New test case.
From-SVN: r110997
