Recover GOTO predictor.

2017-07-31  Jan Hubicka <hubicka@ucw.cz>
	    Martin Liska  <mliska@suse.cz>

	* c-typeck.c (c_finish_goto_label): Build gimple predict
	stament.
2017-07-31  Jan Hubicka <hubicka@ucw.cz>
	    Martin Liska  <mliska@suse.cz>

	* predict.def: Remove old comment and adjust probability.
	* gimplify.c (should_warn_for_implicit_fallthrough): Ignore
	PREDICT statements.
2017-07-31  Jan Hubicka <hubicka@ucw.cz>
	    Martin Liska  <mliska@suse.cz>

	* gcc.dg/predict-15.c: New test.
	* gcc.dg/tree-ssa/vrp24.c: Update scanned pattern.
2017-07-31  Jan Hubicka <hubicka@ucw.cz>
	    Martin Liska  <mliska@suse.cz>

	* pt.c (tsubst_copy): Copy PREDICT_EXPR.
	* semantics.c (finish_goto_stmt): Build gimple predict
	stament.
	* constexpr.c (potential_constant_expression_1): Handle
	PREDICT_EXPR.

Co-Authored-By: Martin Liska <mliska@suse.cz>

From-SVN: r250737