Make opt_pass and gcc::pass_manager be GC-managed

Make opt_pass and gcc::pass_manager be GC-managed

2013-08-20  David Malcolm  <dmalcolm@redhat.com>

	Make opt_pass and gcc::pass_manager be GC-managed, so that pass
	instances can own GC refs.

	* Makefile.in (GTFILES): Add pass_manager.h and tree-pass.h.
	* context.c (gcc::context::gt_ggc_mx): Traverse passes_.
	(gcc::context::gt_pch_nx): Likewise.
	(gcc::context::gt_pch_nx):  Likewise.
	* ggc.h (gt_ggc_mx <T>): New.
	(gt_pch_nx_with_op <T>): New.
	(gt_pch_nx <T>): New.
	* passes.c (opt_pass::gt_ggc_mx): New.
	(opt_pass::gt_pch_nx): New.
	(opt_pass::gt_pch_nx_with_op): New.
	(pass_manager::gt_ggc_mx): New.
	(pass_manager::gt_pch_nx): New.
	(pass_manager::gt_pch_nx_with_op): New.
	(pass_manager::operator new): Use
	ggc_internal_cleared_alloc_stat rather than xcalloc.
	* pass_manager.h (class pass_manager): Add GTY((user)) marking.
	(pass_manager::gt_ggc_mx): New.
	(pass_manager::gt_pch_nx): New.
	(pass_manager::gt_pch_nx_with_op): New.
	* tree-pass.h (class opt_pass): Add GTY((user)) marking.
	(opt_pass::operator new): New.
	(opt_pass::gt_ggc_mx): New.
	(opt_pass::gt_pch_nx): New.
	(opt_pass::gt_pch_nx_with_op): New.

From-SVN: r201865