In dse.c, remove alias hash tables that are never set.

In dse.c, remove alias hash tables that are never set.

Remove conditions that are then never true.
Remove functions that are then never called.
Remove variables that are then never read.

Index: gcc/ChangeLog

2013-03-29  Lawrence Crowl  <crowl@google.com>

	* dse.c (clear_alias_sets): Remove never set.
	(disqualified_clear_alias_sets): Remove never set.
	(clear_alias_mode_pool): Remove never set.
	(dse_step0): Remove condition that is never true.
	(canon_address): Remove condition that is never true.
	(dse_step7): Remove condition that is never true.
	(rest_of_handle_dse): Remove condition that is never true.
	(rest_of_handle_dse::did_global): Remove never read from above.
	(dse_step2_spill): Remove never called from above.
	(dse_step5_spill): Remove never called from above.

From-SVN: r197272