re PR rtl-optimization/49936 (IRA handles CANNOT_CHANGE_MODE_CLASS poorly, + spills to memory on 4.7)

2011-08-19  Vladimir Makarov  <vmakarov@redhat.com>

	PR rtl-optimization/49936
	* ira.c (ira_init_register_move_cost): Ignore too small subclasses
	for calculation of max register move costs.

From-SVN: r177916