trans-mem (collect_bb2reg): Stop scanning at irrevocable

trans-mem (collect_bb2reg): Stop scanning at irrevocable

	* trans-mem (collect_bb2reg): Stop scanning at irrevocable
	* blocks.
	(get_bb_regions_instrumented): Add new traverse_clone argument and
	use it.
	(expand_regions_1): Same.
	(expand_region): Same.
	(execute_tm_mark): Pass new argument to expand_regions.
	(expand_block_edges): Pass new argument to
	get_bb_regions_instrumented.
testsuite/
	* g++.dg/tm/pr51516.C: Adjust for uninstrumented code path.
	* gcc.dg/tm/clone-1.c: New test.

From-SVN: r193633