Add limit for maximal alignment options (PR c/84310).

Add limit for maximal alignment options (PR c/84310).

2018-02-20  Martin Liska  <mliska@suse.cz>

	PR c/84310
	PR target/79747
	* final.c (shorten_branches): Build align_tab array with one
	more element.
	* opts.c (finish_options): Add alignment option limit check.
	(MAX_CODE_ALIGN): Likewise.
	(MAX_CODE_ALIGN_VALUE): Likewise.
	* doc/invoke.texi: Document maximum allowed option value for
	all -falign-* options.
2018-02-20  Martin Liska  <mliska@suse.cz>

	PR c/84310
	PR target/79747
	* gcc.target/i386/pr84310.c: New test.
	* gcc.target/i386/pr84310-2.c: Likewise.

From-SVN: r257842