2016-05-20  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/29756
	* tree.def (BIT_INSERT_EXPR): New tcc_expression tree code.
	* expr.c (expand_expr_real_2): Handle BIT_INSERT_EXPR.
	* fold-const.c (operand_equal_p): Likewise.
	(fold_ternary_loc): Add constant folding of BIT_INSERT_EXPR.
	* gimplify.c (gimplify_expr): Handle BIT_INSERT_EXPR.
	* tree-inline.c (estimate_operator_cost): Likewise.
	* tree-pretty-print.c (dump_generic_node): Likewise.
	* tree-ssa-operands.c (get_expr_operands): Likewise.
	* cfgexpand.c (expand_debug_expr): Likewise.
	* gimple-pretty-print.c (dump_ternary_rhs): Likewise.
	* gimple.c (get_gimple_rhs_num_ops): Handle BIT_INSERT_EXPR.
	* tree-cfg.c (verify_gimple_assign_ternary): Verify BIT_INSERT_EXPR.

	* tree-ssa.c (non_rewritable_lvalue_p): We can rewrite
	vector inserts using BIT_FIELD_REF or MEM_REF on the lhs.
	(execute_update_addresses_taken): Do it.

	* gcc.dg/tree-ssa/vector-6.c: New testcase.

From-SVN: r236501