* fold-const.c (tree_expr_nonzero_p): Add function prototype.
(fold) <EQ_EXPR>: Move tree_expr_nonzero_p optimization from
fold_relational_const to here, i.e. "(x | 5) == 0" -> false.
(fold) (UNEQ_EXPR>: Add optimizations for unordered comparisons
of the form "x op x" where op is UNLE, UNGE, UNEQ or LTGT.
(fold_relational_const): Tidy up handling of floating point
comparisons by calling real_compare. Remove tree_expr_nonzero_p
transformation; fold_relational_const assumes constant operands.
From-SVN: r84916
